Class: Google::Cloud::DiscoveryEngine::V1beta::SearchRequest

Inherits:

Object

Object
Google::Cloud::DiscoveryEngine::V1beta::SearchRequest

show all

Extended by:: Protobuf::MessageExts::ClassMethods

Includes:: Protobuf::MessageExts

Defined in:: proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb

Overview

Request message for SearchService.Search method.

Defined Under Namespace

Modules: RankingExpressionBackend, RelevanceThreshold Classes: BoostSpec, ContentSearchSpec, CrowdingSpec, CustomRankingParams, DataStoreSpec, DisplaySpec, EmbeddingSpec, FacetSpec, ImageQuery, NaturalLanguageQueryUnderstandingSpec, ParamsEntry, PersonalizationSpec, QueryExpansionSpec, RelevanceFilterSpec, RelevanceScoreSpec, SearchAddonSpec, SearchAsYouTypeSpec, SessionSpec, SpellCorrectionSpec, UserLabelsEntry

Instance Attribute Summary collapse

#boost_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec
Boost specification to boost certain documents.
#branch ⇒ ::String
The branch resource name, such as projects/*/locations/global/collections/default_collection/dataStores/default_data_store/branches/0.
#canonical_filter ⇒ ::String
The default filter that is applied when a user performs a search without checking any filters on the search page.
#content_search_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec
A specification for configuring the behavior of content search.
#crowding_specs ⇒ ::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec>
Optional.
#custom_ranking_params ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CustomRankingParams
Optional.
#data_store_specs ⇒ ::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DataStoreSpec>
Specifications that define the specific DataStores to be searched, along with configurations for those data stores.
#display_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec
Optional.
#embedding_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec
Uses the provided embedding to do additional semantic document retrieval.
#entity ⇒ ::String
Optional.
#facet_specs ⇒ ::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec>
Facet specifications for faceted search.
#filter ⇒ ::String
The filter syntax consists of an expression language for constructing a predicate from one or more fields of the documents being filtered.
#image_query ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ImageQuery
Raw image query.
#language_code ⇒ ::String
The BCP-47 language code, such as "en-US" or "sr-Latn".
#natural_language_query_understanding_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec
Optional.
#num_results_per_data_store ⇒ ::Integer
Optional.
#offset ⇒ ::Integer
A 0-indexed integer that specifies the current offset (that is, starting result location, amongst the Documents deemed by the API as relevant) in search results.
#one_box_page_size ⇒ ::Integer
The maximum number of results to return for OneBox.
#order_by ⇒ ::String
The order in which documents are returned.
#page_categories ⇒ ::Array<::String>
Optional.
#page_size ⇒ ::Integer
Maximum number of Documents to return.
#page_token ⇒ ::String
A page token received from a previous SearchService.Search call.
#params ⇒ ::Google::Protobuf::Map{::String => ::Google::Protobuf::Value}
Additional search parameters.
#personalization_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec
The specification for personalization.
#query ⇒ ::String
Raw search query.
#query_expansion_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec
The query expansion specification that specifies the conditions under which query expansion occurs.
#ranking_expression ⇒ ::String
Optional.
#ranking_expression_backend ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RankingExpressionBackend
Optional.
#region_code ⇒ ::String
The Unicode country/region code (CLDR) of a location, such as "US" and "419".
#relevance_filter_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec
Optional.
#relevance_score_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceScoreSpec
Optional.
#relevance_threshold ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold
The global relevance threshold of the search results.
#safe_search ⇒ ::Boolean
Whether to turn on safe search.
#search_addon_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAddonSpec
Optional.
#search_as_you_type_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec
Search as you type configuration.
#serving_config ⇒ ::String
Required.
#session ⇒ ::String
The session resource name.
#session_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SessionSpec
Session specification.
#spell_correction_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec
The spell correction specification that specifies the mode under which spell correction takes effect.
#user_info ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::UserInfo
Information about the end user.
#user_labels ⇒ ::Google::Protobuf::Map{::String => ::String}
The user labels applied to a resource must meet the following requirements:.
#user_pseudo_id ⇒ ::String
Optional.

Instance Attribute Details

#boost_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec`

Returns Boost specification to boost certain documents. For more information on boosting, see Boosting.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec) —
Boost specification to boost certain documents. For more information on boosting, see Boosting

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#branch ⇒ `::String`

Returns The branch resource name, such as projects/*/locations/global/collections/default_collection/dataStores/default_data_store/branches/0.

Use default_branch as the branch ID or leave this field empty, to search documents under the default branch.

Returns:

(::String) —
The branch resource name, such as projects/*/locations/global/collections/default_collection/dataStores/default_data_store/branches/0.

Use default_branch as the branch ID or leave this field empty, to search documents under the default branch.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#canonical_filter ⇒ `::String`

Returns The default filter that is applied when a user performs a search without checking any filters on the search page.

The filter applied to every search request when quality improvement such as query expansion is needed. In the case a query does not have a sufficient amount of results this filter will be used to determine whether or not to enable the query expansion flow. The original filter will still be used for the query expanded search. This field is strongly recommended to achieve high search quality.

For more information about filter syntax, see SearchRequest.filter.

Returns:

(::String) —
The default filter that is applied when a user performs a search without checking any filters on the search page.

The filter applied to every search request when quality improvement such as query expansion is needed. In the case a query does not have a sufficient amount of results this filter will be used to determine whether or not to enable the query expansion flow. The original filter will still be used for the query expanded search. This field is strongly recommended to achieve high search quality.

For more information about filter syntax, see SearchRequest.filter.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#content_search_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec`

Returns A specification for configuring the behavior of content search.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec) —
A specification for configuring the behavior of content search.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#crowding_specs ⇒ `::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec>`

Returns Optional. Crowding specifications for improving result diversity. If multiple CrowdingSpecs are specified, crowding will be evaluated on each unique combination of the field values, and max_count will be the maximum value of max_count across all CrowdingSpecs. For example, if the first CrowdingSpec has field = "color" and max_count = 3, and the second CrowdingSpec has field = "size" and max_count = 2, then after 3 documents that share the same color AND size have been returned, subsequent ones should be removed or demoted.

Returns:

(::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec>) —
Optional. Crowding specifications for improving result diversity. If multiple CrowdingSpecs are specified, crowding will be evaluated on each unique combination of the field values, and max_count will be the maximum value of max_count across all CrowdingSpecs. For example, if the first CrowdingSpec has field = "color" and max_count = 3, and the second CrowdingSpec has field = "size" and max_count = 2, then after 3 documents that share the same color AND size have been returned, subsequent ones should be removed or demoted.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#custom_ranking_params ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CustomRankingParams`

Returns Optional. Optional configuration for the Custom Ranking feature.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CustomRankingParams) —
Optional. Optional configuration for the Custom Ranking feature.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#data_store_specs ⇒ `::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DataStoreSpec>`

Returns Specifications that define the specific DataStores to be searched, along with configurations for those data stores. This is only considered for Engines with multiple data stores. For engines with a single data store, the specs directly under SearchRequest should be used.

Returns:

(::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DataStoreSpec>) —
Specifications that define the specific DataStores to be searched, along with configurations for those data stores. This is only considered for Engines with multiple data stores. For engines with a single data store, the specs directly under SearchRequest should be used.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#display_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec`

Returns Optional. Config for display feature, like match highlighting on search results.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec) —
Optional. Config for display feature, like match highlighting on search results.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#embedding_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec`

Returns Uses the provided embedding to do additional semantic document retrieval. The retrieval is based on the dot product of SearchRequest.EmbeddingSpec.EmbeddingVector.vector and the document embedding that is provided in SearchRequest.EmbeddingSpec.EmbeddingVector.field_path.

If SearchRequest.EmbeddingSpec.EmbeddingVector.field_path is not provided, it will use ServingConfig.EmbeddingConfig.field_path.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec) —
Uses the provided embedding to do additional semantic document retrieval. The retrieval is based on the dot product of SearchRequest.EmbeddingSpec.EmbeddingVector.vector and the document embedding that is provided in SearchRequest.EmbeddingSpec.EmbeddingVector.field_path.

If SearchRequest.EmbeddingSpec.EmbeddingVector.field_path is not provided, it will use ServingConfig.EmbeddingConfig.field_path.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#entity ⇒ `::String`

Returns Optional. The entity for customers that may run multiple different entities, domains, sites or regions, for example, "Google US", "Google Ads", "Waymo", "google.com", "youtube.com", etc. If this is set, it should be exactly matched with UserEvent.entity to get search results boosted by entity.

Returns:

(::String) —
Optional. The entity for customers that may run multiple different entities, domains, sites or regions, for example, "Google US", "Google Ads", "Waymo", "google.com", "youtube.com", etc. If this is set, it should be exactly matched with UserEvent.entity to get search results boosted by entity.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

Returns Facet specifications for faceted search. If empty, no facets are returned.

A maximum of 100 values are allowed. Otherwise, an INVALID_ARGUMENT error is returned.

Returns:

(::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec>) —
Facet specifications for faceted search. If empty, no facets are returned.

A maximum of 100 values are allowed. Otherwise, an INVALID_ARGUMENT error is returned.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#filter ⇒ `::String`

Returns The filter syntax consists of an expression language for constructing a predicate from one or more fields of the documents being filtered. Filter expression is case-sensitive.

If this field is unrecognizable, an INVALID_ARGUMENT is returned.

Filtering in Vertex AI Search is done by mapping the LHS filter key to a key property defined in the Vertex AI Search backend -- this mapping is defined by the customer in their schema. For example a media customer might have a field 'name' in their schema. In this case the filter would look like this: filter --> name:'ANY("king kong")'

For more information about filtering including syntax and filter operators, see Filter.

Returns:

(::String) —
The filter syntax consists of an expression language for constructing a predicate from one or more fields of the documents being filtered. Filter expression is case-sensitive.

If this field is unrecognizable, an INVALID_ARGUMENT is returned.

Filtering in Vertex AI Search is done by mapping the LHS filter key to a key property defined in the Vertex AI Search backend -- this mapping is defined by the customer in their schema. For example a media customer might have a field 'name' in their schema. In this case the filter would look like this: filter --> name:'ANY("king kong")'

For more information about filtering including syntax and filter operators, see Filter

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#image_query ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ImageQuery`

Returns Raw image query.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ImageQuery) —
Raw image query.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#language_code ⇒ `::String`

Returns The BCP-47 language code, such as "en-US" or "sr-Latn". For more information, see Standard fields. This field helps to better interpret the query. If a value isn't specified, the query language code is automatically detected, which may not be accurate.

Returns:

(::String) —
The BCP-47 language code, such as "en-US" or "sr-Latn". For more information, see Standard fields. This field helps to better interpret the query. If a value isn't specified, the query language code is automatically detected, which may not be accurate.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#natural_language_query_understanding_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec`

Returns Optional. Config for natural language query understanding capabilities, such as extracting structured field filters from the query. Refer to this documentation for more information. If naturalLanguageQueryUnderstandingSpec is not specified, no additional natural language query understanding will be done.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec) —
Optional. Config for natural language query understanding capabilities, such as extracting structured field filters from the query. Refer to this documentation for more information. If naturalLanguageQueryUnderstandingSpec is not specified, no additional natural language query understanding will be done.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#num_results_per_data_store ⇒ `::Integer`

Returns Optional. The maximum number of results to retrieve from each data store. If not specified, it will use the SearchRequest.DataStoreSpec.num_results if provided, otherwise there is no limit.

Returns:

(::Integer) —
Optional. The maximum number of results to retrieve from each data store. If not specified, it will use the SearchRequest.DataStoreSpec.num_results if provided, otherwise there is no limit.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#offset ⇒ `::Integer`

Returns A 0-indexed integer that specifies the current offset (that is, starting result location, amongst the Documents deemed by the API as relevant) in search results. This field is only considered if page_token is unset.

If this field is negative, an INVALID_ARGUMENT is returned.

A large offset may be capped to a reasonable threshold.

Returns:

(::Integer) —
A 0-indexed integer that specifies the current offset (that is, starting result location, amongst the Documents deemed by the API as relevant) in search results. This field is only considered if page_token is unset.

If this field is negative, an INVALID_ARGUMENT is returned.

A large offset may be capped to a reasonable threshold.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#one_box_page_size ⇒ `::Integer`

Returns The maximum number of results to return for OneBox. This applies to each OneBox type individually. Default number is 10.

Returns:

(::Integer) —
The maximum number of results to return for OneBox. This applies to each OneBox type individually. Default number is 10.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#order_by ⇒ `::String`

Returns The order in which documents are returned. Documents can be ordered by a field in an Document object. Leave it unset if ordered by relevance. order_by expression is case-sensitive.

For more information on ordering the website search results, see Order web search results. For more information on ordering the healthcare search results, see Order healthcare search results. If this field is unrecognizable, an INVALID_ARGUMENT is returned.

Returns:

(::String) —
The order in which documents are returned. Documents can be ordered by a field in an Document object. Leave it unset if ordered by relevance. order_by expression is case-sensitive.

For more information on ordering the website search results, see Order web search results. For more information on ordering the healthcare search results, see Order healthcare search results. If this field is unrecognizable, an INVALID_ARGUMENT is returned.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#page_categories ⇒ `::Array<::String>`

Returns Optional. The categories associated with a category page. Must be set for category navigation queries to achieve good search quality. The format should be the same as PageInfo.page_category. This field is the equivalent of the query for browse (navigation) queries. It's used by the browse model when the query is empty.

If the field is empty, it will not be used by the browse model. If the field contains more than one element, only the first element will be used.

To represent full path of a category, use '>' character to separate different hierarchies. If '>' is part of the category name, replace it with other character(s). For example, Graphics Cards > RTX>4090 > Founders Edition where "RTX > 4090" represents one level, can be rewritten as `Graphics Cards > RTX_4090

Founders Edition`.

Returns:

(::Array<::String>) —
Optional. The categories associated with a category page. Must be set for category navigation queries to achieve good search quality. The format should be the same as PageInfo.page_category. This field is the equivalent of the query for browse (navigation) queries. It's used by the browse model when the query is empty.

If the field is empty, it will not be used by the browse model. If the field contains more than one element, only the first element will be used.

To represent full path of a category, use '>' character to separate different hierarchies. If '>' is part of the category name, replace it with other character(s). For example, Graphics Cards > RTX>4090 > Founders Edition where "RTX > 4090" represents one level, can be rewritten as `Graphics Cards > RTX_4090

Founders Edition`

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#page_size ⇒ `::Integer`

Returns Maximum number of Documents to return. The maximum allowed value depends on the data type. Values above the maximum value are coerced to the maximum value.

Websites with basic indexing: Default 10, Maximum 25.
Websites with advanced indexing: Default 25, Maximum 50.
Other: Default 50, Maximum 100.

If this field is negative, an INVALID_ARGUMENT is returned.

Returns:

(::Integer) —
Maximum number of Documents to return. The maximum allowed value depends on the data type. Values above the maximum value are coerced to the maximum value.
- Websites with basic indexing: Default 10, Maximum 25.
- Websites with advanced indexing: Default 25, Maximum 50.
- Other: Default 50, Maximum 100.
If this field is negative, an INVALID_ARGUMENT is returned.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#page_token ⇒ `::String`

Returns A page token received from a previous SearchService.Search call. Provide this to retrieve the subsequent page.

When paginating, all other parameters provided to SearchService.Search must match the call that provided the page token. Otherwise, an INVALID_ARGUMENT error is returned.

Returns:

(::String) —
A page token received from a previous SearchService.Search call. Provide this to retrieve the subsequent page.

When paginating, all other parameters provided to SearchService.Search must match the call that provided the page token. Otherwise, an INVALID_ARGUMENT error is returned.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#params ⇒ `::Google::Protobuf::Map{::String => ::Google::Protobuf::Value}`

Returns Additional search parameters.

For public website search only, supported values are:

user_country_code: string. Default empty. If set to non-empty, results are restricted or boosted based on the location provided. For example, user_country_code: "au"

For available codes see Country Codes

search_type: double. Default empty. Enables non-webpage searching depending on the value. The only valid non-default value is 1, which enables image searching. For example, search_type: 1.

Returns:

(::Google::Protobuf::Map{::String => ::Google::Protobuf::Value}) —
Additional search parameters.

For public website search only, supported values are:
- user_country_code: string. Default empty. If set to non-empty, results are restricted or boosted based on the location provided. For example, user_country_code: "au"
For available codes see Country Codes
- search_type: double. Default empty. Enables non-webpage searching depending on the value. The only valid non-default value is 1, which enables image searching. For example, search_type: 1

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#personalization_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec`

Returns The specification for personalization.

Notice that if both ServingConfig.personalization_spec and SearchRequest.personalization_spec are set, SearchRequest.personalization_spec overrides ServingConfig.personalization_spec.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec) —
The specification for personalization.

Notice that if both ServingConfig.personalization_spec and SearchRequest.personalization_spec are set, SearchRequest.personalization_spec overrides ServingConfig.personalization_spec.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#query ⇒ `::String`

Returns Raw search query.

Returns:

(::String) —
Raw search query.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#query_expansion_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec`

Returns The query expansion specification that specifies the conditions under which query expansion occurs.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec) —
The query expansion specification that specifies the conditions under which query expansion occurs.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#ranking_expression ⇒ `::String`

Returns Optional. The ranking expression controls the customized ranking on retrieval documents. This overrides ServingConfig.ranking_expression. The syntax and supported features depend on the ranking_expression_backend value. If ranking_expression_backend is not provided, it defaults to RANK_BY_EMBEDDING.

If ranking_expression_backend is not provided or set to RANK_BY_EMBEDDING, it should be a single function or multiple functions that are joined by "+".

ranking_expression = function, { " + ", function };

Supported functions:

double * relevance_score
double * dotProduct(embedding_field_path)

Function variables:

relevance_score: pre-defined keywords, used for measure relevance between query and document.
embedding_field_path: the document embedding field used with query embedding vector.
dotProduct: embedding function between embedding_field_path and query embedding vector.

Example ranking expression:

If document has an embedding field doc_embedding, the ranking expression could be 0.5 * relevance_score + 0.3 * dotProduct(doc_embedding).

If ranking_expression_backend is set to RANK_BY_FORMULA, the following expression types (and combinations of those chained using + or

operators) are supported:
- double
- signal
- log(signal)
- exp(signal)
- rr(signal, double > 0) -- reciprocal rank transformation with second argument being a denominator constant.
- is_nan(signal) -- returns 0 if signal is NaN, 1 otherwise.
- fill_nan(signal1, signal2 | double) -- if signal1 is NaN, returns signal2 | double, else returns signal1.

Here are a few examples of ranking formulas that use the supported ranking expression types:

0.2 * semantic_similarity_score + 0.8 * log(keyword_similarity_score) -- mostly rank by the logarithm of keyword_similarity_score with slight semantic_smilarity_score adjustment.
0.2 * exp(fill_nan(semantic_similarity_score, 0)) + 0.3 * is_nan(keyword_similarity_score) -- rank by the exponent of semantic_similarity_score filling the value with 0 if it's NaN, also add constant 0.3 adjustment to the final score if semantic_similarity_score is NaN.
0.2 * rr(semantic_similarity_score, 16) + 0.8 * rr(keyword_similarity_score, 16) -- mostly rank by the reciprocal rank of keyword_similarity_score with slight adjustment of reciprocal rank of semantic_smilarity_score.

The following signals are supported:

semantic_similarity_score: semantic similarity adjustment that is calculated using the embeddings generated by a proprietary Google model. This score determines how semantically similar a search query is to a document.
keyword_similarity_score: keyword match adjustment uses the Best Match 25 (BM25) ranking function. This score is calculated using a probabilistic model to estimate the probability that a document is relevant to a given query.
relevance_score: semantic relevance adjustment that uses a proprietary Google model to determine the meaning and intent behind a user's query in context with the content in the documents.
pctr_rank: predicted conversion rate adjustment as a rank use predicted Click-through rate (pCTR) to gauge the relevance and attractiveness of a search result from a user's perspective. A higher pCTR suggests that the result is more likely to satisfy the user's query and intent, making it a valuable signal for ranking.
freshness_rank: freshness adjustment as a rank
document_age: The time in hours elapsed since the document was last updated, a floating-point number (e.g., 0.25 means 15 minutes).
topicality_rank: topicality adjustment as a rank. Uses proprietary Google model to determine the keyword-based overlap between the query and the document.
base_rank: the default rank of the result
media_actor_match: whether the media actor matches the query
media_director_match: whether the media director matches the query
media_genre_match: whether the media genre matches the query
media_language_match: whether the media language matches the query
media_title_match: whether the media title matches the query
media_prefix_similarity_rank: prefix similarity rank for media results
media_semantic_similarity_rank: semantic similarity rank for media results.

Returns:

(::String) —
Optional. The ranking expression controls the customized ranking on retrieval documents. This overrides ServingConfig.ranking_expression. The syntax and supported features depend on the ranking_expression_backend value. If ranking_expression_backend is not provided, it defaults to RANK_BY_EMBEDDING.

If ranking_expression_backend is not provided or set to RANK_BY_EMBEDDING, it should be a single function or multiple functions that are joined by "+".
- ranking_expression = function, { " + ", function };
Supported functions:
- double * relevance_score
- double * dotProduct(embedding_field_path)
Function variables:
- relevance_score: pre-defined keywords, used for measure relevance between query and document.
- embedding_field_path: the document embedding field used with query embedding vector.
- dotProduct: embedding function between embedding_field_path and query embedding vector.
Example ranking expression:

If document has an embedding field doc_embedding, the ranking expression could be 0.5 * relevance_score + 0.3 * dotProduct(doc_embedding).

If ranking_expression_backend is set to RANK_BY_FORMULA, the following expression types (and combinations of those chained using + or
- operators) are supported:
  - double
  - signal
  - log(signal)
  - exp(signal)
  - rr(signal, double > 0) -- reciprocal rank transformation with second argument being a denominator constant.
  - is_nan(signal) -- returns 0 if signal is NaN, 1 otherwise.
  - fill_nan(signal1, signal2 | double) -- if signal1 is NaN, returns signal2 | double, else returns signal1.
Here are a few examples of ranking formulas that use the supported ranking expression types:
- 0.2 * semantic_similarity_score + 0.8 * log(keyword_similarity_score) -- mostly rank by the logarithm of keyword_similarity_score with slight semantic_smilarity_score adjustment.
- 0.2 * exp(fill_nan(semantic_similarity_score, 0)) + 0.3 * is_nan(keyword_similarity_score) -- rank by the exponent of semantic_similarity_score filling the value with 0 if it's NaN, also add constant 0.3 adjustment to the final score if semantic_similarity_score is NaN.
- 0.2 * rr(semantic_similarity_score, 16) + 0.8 * rr(keyword_similarity_score, 16) -- mostly rank by the reciprocal rank of keyword_similarity_score with slight adjustment of reciprocal rank of semantic_smilarity_score.
The following signals are supported:
- semantic_similarity_score: semantic similarity adjustment that is calculated using the embeddings generated by a proprietary Google model. This score determines how semantically similar a search query is to a document.
- keyword_similarity_score: keyword match adjustment uses the Best Match 25 (BM25) ranking function. This score is calculated using a probabilistic model to estimate the probability that a document is relevant to a given query.
- relevance_score: semantic relevance adjustment that uses a proprietary Google model to determine the meaning and intent behind a user's query in context with the content in the documents.
- pctr_rank: predicted conversion rate adjustment as a rank use predicted Click-through rate (pCTR) to gauge the relevance and attractiveness of a search result from a user's perspective. A higher pCTR suggests that the result is more likely to satisfy the user's query and intent, making it a valuable signal for ranking.
- freshness_rank: freshness adjustment as a rank
- document_age: The time in hours elapsed since the document was last updated, a floating-point number (e.g., 0.25 means 15 minutes).
- topicality_rank: topicality adjustment as a rank. Uses proprietary Google model to determine the keyword-based overlap between the query and the document.
- base_rank: the default rank of the result
- media_actor_match: whether the media actor matches the query
- media_director_match: whether the media director matches the query
- media_genre_match: whether the media genre matches the query
- media_language_match: whether the media language matches the query
- media_title_match: whether the media title matches the query
- media_prefix_similarity_rank: prefix similarity rank for media results
- media_semantic_similarity_rank: semantic similarity rank for media results

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#ranking_expression_backend ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RankingExpressionBackend`

Returns Optional. The backend to use for the ranking expression evaluation.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RankingExpressionBackend) —
Optional. The backend to use for the ranking expression evaluation.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#region_code ⇒ `::String`

Returns The Unicode country/region code (CLDR) of a location, such as "US" and "419". For more information, see Standard fields. If set, then results will be boosted based on the region_code provided.

Returns:

(::String) —
The Unicode country/region code (CLDR) of a location, such as "US" and "419". For more information, see Standard fields. If set, then results will be boosted based on the region_code provided.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#relevance_filter_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec`

Returns Optional. The granular relevance filtering specification.

If not specified, the global relevance_threshold will be used for all sub-searches. If specified, this overrides the global relevance_threshold to use thresholds on a per sub-search basis.

This feature is currently supported only for custom and site search.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec) —
Optional. The granular relevance filtering specification.

If not specified, the global relevance_threshold will be used for all sub-searches. If specified, this overrides the global relevance_threshold to use thresholds on a per sub-search basis.

This feature is currently supported only for custom and site search.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#relevance_score_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceScoreSpec`

Returns Optional. The specification for returning the relevance score.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceScoreSpec) —
Optional. The specification for returning the relevance score.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#relevance_threshold ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold`

Returns The global relevance threshold of the search results.

Defaults to Google defined threshold, leveraging a balance of precision and recall to deliver both highly accurate results and comprehensive coverage of relevant information.

If more granular relevance filtering is required, use the relevance_filter_spec instead.

This feature is not supported for healthcare search.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold) —
The global relevance threshold of the search results.

Defaults to Google defined threshold, leveraging a balance of precision and recall to deliver both highly accurate results and comprehensive coverage of relevant information.

If more granular relevance filtering is required, use the relevance_filter_spec instead.

This feature is not supported for healthcare search.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#safe_search ⇒ `::Boolean`

Returns Whether to turn on safe search. This is only supported for website search.

Returns:

(::Boolean) —
Whether to turn on safe search. This is only supported for website search.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#search_addon_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAddonSpec`

Returns Optional. SearchAddonSpec is used to disable add-ons for search as per new repricing model. This field is only supported for search requests.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAddonSpec) —
Optional. SearchAddonSpec is used to disable add-ons for search as per new repricing model. This field is only supported for search requests.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#search_as_you_type_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec`

Returns Search as you type configuration. Only supported for the IndustryVertical.MEDIA vertical.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec) —
Search as you type configuration. Only supported for the IndustryVertical.MEDIA vertical.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#serving_config ⇒ `::String`

Returns Required. The resource name of the Search serving config, such as projects/*/locations/global/collections/default_collection/engines/*/servingConfigs/default_serving_config, or projects/*/locations/global/collections/default_collection/dataStores/default_data_store/servingConfigs/default_serving_config. This field is used to identify the serving configuration name, set of models used to make the search.

Returns:

(::String) —
Required. The resource name of the Search serving config, such as projects/*/locations/global/collections/default_collection/engines/*/servingConfigs/default_serving_config, or projects/*/locations/global/collections/default_collection/dataStores/default_data_store/servingConfigs/default_serving_config. This field is used to identify the serving configuration name, set of models used to make the search.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#session ⇒ `::String`

Returns The session resource name. Optional.

Session allows users to do multi-turn /search API calls or coordination between /search API calls and /answer API calls.

Example #1 (multi-turn /search API calls): Call /search API with the session ID generated in the first call. Here, the previous search query gets considered in query standing. I.e., if the first query is "How did Alphabet do in 2022?" and the current query is "How about 2023?", the current query will be interpreted as "How did Alphabet do in 2023?".

Example #2 (coordination between /search API calls and /answer API calls): Call /answer API with the session ID generated in the first call. Here, the answer generation happens in the context of the search results from the first search call.

Returns:

(::String) —
The session resource name. Optional.

Session allows users to do multi-turn /search API calls or coordination between /search API calls and /answer API calls.

Example #1 (multi-turn /search API calls): Call /search API with the session ID generated in the first call. Here, the previous search query gets considered in query standing. I.e., if the first query is "How did Alphabet do in 2022?" and the current query is "How about 2023?", the current query will be interpreted as "How did Alphabet do in 2023?".

Example #2 (coordination between /search API calls and /answer API calls): Call /answer API with the session ID generated in the first call. Here, the answer generation happens in the context of the search results from the first search call.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#session_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SessionSpec`

Returns Session specification.

Can be used only when session is set.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SessionSpec) —
Session specification.

Can be used only when session is set.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#spell_correction_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec`

Returns The spell correction specification that specifies the mode under which spell correction takes effect.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec) —
The spell correction specification that specifies the mode under which spell correction takes effect.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#user_info ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::UserInfo`

Returns Information about the end user. Highly recommended for analytics and personalization. UserInfo.user_agent is used to deduce device_type for analytics.

Returns:

(::Google::Cloud::DiscoveryEngine::V1beta::UserInfo) —
Information about the end user. Highly recommended for analytics and personalization. UserInfo.user_agent is used to deduce device_type for analytics.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#user_labels ⇒ `::Google::Protobuf::Map{::String => ::String}`

Returns The user labels applied to a resource must meet the following requirements:

Each resource can have multiple labels, up to a maximum of 64.
Each label must be a key-value pair.
Keys have a minimum length of 1 character and a maximum length of 63 characters and cannot be empty. Values can be empty and have a maximum length of 63 characters.
Keys and values can contain only lowercase letters, numeric characters, underscores, and dashes. All characters must use UTF-8 encoding, and international characters are allowed.
The key portion of a label must be unique. However, you can use the same key with multiple resources.
Keys must start with a lowercase letter or international character.

See Google Cloud Document for more details.

Returns:

(::Google::Protobuf::Map{::String => ::String}) —
The user labels applied to a resource must meet the following requirements:
- Each resource can have multiple labels, up to a maximum of 64.
- Each label must be a key-value pair.
- Keys have a minimum length of 1 character and a maximum length of 63 characters and cannot be empty. Values can be empty and have a maximum length of 63 characters.
- Keys and values can contain only lowercase letters, numeric characters, underscores, and dashes. All characters must use UTF-8 encoding, and international characters are allowed.
- The key portion of a label must be unique. However, you can use the same key with multiple resources.
- Keys must start with a lowercase letter or international character.
See Google Cloud Document for more details.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

#user_pseudo_id ⇒ `::String`

Returns Optional. A unique identifier for tracking visitors. For example, this could be implemented with an HTTP cookie, which should be able to uniquely identify a visitor on a single device. This unique identifier should not change if the visitor logs in or out of the website.

This field should NOT have a fixed value such as unknown_visitor.

This should be the same identifier as UserEvent.user_pseudo_id and CompleteQueryRequest.user_pseudo_id

The field must be a UTF-8 encoded string with a length limit of 128 characters. Otherwise, an INVALID_ARGUMENT error is returned.

Returns:

(::String) —
Optional. A unique identifier for tracking visitors. For example, this could be implemented with an HTTP cookie, which should be able to uniquely identify a visitor on a single device. This unique identifier should not change if the visitor logs in or out of the website.

This field should NOT have a fixed value such as unknown_visitor.

This should be the same identifier as UserEvent.user_pseudo_id and CompleteQueryRequest.user_pseudo_id

The field must be a UTF-8 encoded string with a length limit of 128 characters. Otherwise, an INVALID_ARGUMENT error is returned.

# File 'proto_docs/google/cloud/discoveryengine/v1beta/search_service.rb', line 481

class SearchRequest
  include ::Google::Protobuf::MessageExts
  extend ::Google::Protobuf::MessageExts::ClassMethods

  # Specifies the image query input.
  # @!attribute [rw] image_bytes
  #   @return [::String]
  #     Base64 encoded image bytes. Supported image formats: JPEG, PNG, and
  #     BMP.
  class ImageQuery
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A struct to define data stores to filter on in a search call and
  # configurations for those data stores. Otherwise, an `INVALID_ARGUMENT`
  # error is returned.
  # @!attribute [rw] data_store
  #   @return [::String]
  #     Required. Full resource name of
  #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore}, such as
  #     `projects/{project}/locations/{location}/collections/{collection_id}/dataStores/{data_store_id}`.
  #     The path must include the project number, project id is not supported for
  #     this field.
  # @!attribute [rw] filter
  #   @return [::String]
  #     Optional. Filter specification to filter documents in the data store
  #     specified by data_store field. For more information on filtering, see
  #     [Filtering](https://cloud.google.com/generative-ai-app-builder/docs/filter-search-metadata)
  # @!attribute [rw] boost_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec]
  #     Optional. Boost specification to boost certain documents.
  #     For more information on boosting, see
  #     [Boosting](https://cloud.google.com/generative-ai-app-builder/docs/boost-search-results)
  # @!attribute [rw] custom_search_operators
  #   @return [::String]
  #     Optional. Custom search operators which if specified will be used to
  #     filter results from workspace data stores. For more information on custom
  #     search operators, see
  #     [SearchOperators](https://support.google.com/cloudsearch/answer/6172299).
  # @!attribute [rw] num_results
  #   @return [::Integer]
  #     Optional. The maximum number of results to retrieve from this data store.
  #     If not specified, it will use the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     if provided, otherwise there is no limit. If both this field and
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#num_results_per_data_store SearchRequest.num_results_per_data_store}
  #     are specified, this field will be used.
  class DataStoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # A facet specification to perform faceted search.
  # @!attribute [rw] facet_key
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey]
  #     Required. The facet key specification.
  # @!attribute [rw] limit
  #   @return [::Integer]
  #     Maximum facet values that are returned for this facet. If
  #     unspecified, defaults to 20. The maximum allowed value is 300. Values
  #     above 300 are coerced to 300.
  #     For aggregation in healthcare search, when the [FacetKey.key] is
  #     "healthcare_aggregation_key", the limit will be overridden to
  #     10,000 internally, regardless of the value set here.
  #
  #     If this field is negative, an  `INVALID_ARGUMENT`  is returned.
  # @!attribute [rw] excluded_filter_keys
  #   @return [::Array<::String>]
  #     List of keys to exclude when faceting.
  #
  #     By default,
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     is not excluded from the filter unless it is listed in this field.
  #
  #     Listing a facet key in this field allows its values to appear as facet
  #     results, even when they are filtered out of search results. Using this
  #     field does not affect what search results are returned.
  #
  #     For example, suppose there are 100 documents with the color facet "Red"
  #     and 200 documents with the color facet "Blue". A query containing the
  #     filter "color:ANY("Red")" and having "color" as
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#key FacetKey.key}
  #     would by default return only "Red" documents in the search results, and
  #     also return "Red" with count 100 as the only color facet. Although there
  #     are also blue documents available, "Blue" would not be shown as an
  #     available facet value.
  #
  #     If "color" is listed in "excludedFilterKeys", then the query returns the
  #     facet values "Red" with count 100 and "Blue" with count 200, because the
  #     "color" key is now excluded from the filter. Because this field doesn't
  #     affect search results, the search results are still correctly filtered to
  #     return only "Red" documents.
  #
  #     A maximum of 100 values are allowed. Otherwise, an  `INVALID_ARGUMENT`
  #     error is returned.
  # @!attribute [rw] enable_dynamic_position
  #   @return [::Boolean]
  #     Enables dynamic position for this facet. If set to true, the position of
  #     this facet among all facets in the response is determined automatically.
  #     If dynamic facets are enabled, it is ordered together.
  #     If set to false, the position of this facet in the
  #     response is the same as in the request, and it is ranked before
  #     the facets with dynamic position enable and all dynamic facets.
  #
  #     For example, you may always want to have rating facet returned in
  #     the response, but it's not necessarily to always display the rating facet
  #     at the top. In that case, you can set enable_dynamic_position to true so
  #     that the position of rating facet in response is determined
  #     automatically.
  #
  #     Another example, assuming you have the following facets in the request:
  #
  #     * "rating", enable_dynamic_position = true
  #
  #     * "price", enable_dynamic_position = false
  #
  #     * "brands", enable_dynamic_position = false
  #
  #     And also you have a dynamic facets enabled, which generates a facet
  #     `gender`. Then the final order of the facets in the response can be
  #     ("price", "brands", "rating", "gender") or ("price", "brands", "gender",
  #     "rating") depends on how API orders "gender" and "rating" facets.
  #     However, notice that "price" and "brands" are always
  #     ranked at first and second position because their enable_dynamic_position
  #     is false.
  class FacetSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specifies how a facet is computed.
    # @!attribute [rw] key
    #   @return [::String]
    #     Required. Supported textual and numerical facet keys in
    #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object, over
    #     which the facet values are computed. Facet key is case-sensitive.
    # @!attribute [rw] intervals
    #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::Interval>]
    #     Set only if values should be bucketed into intervals. Must be set
    #     for facets with numerical values. Must not be set for facet with text
    #     values. Maximum number of intervals is 30.
    # @!attribute [rw] restricted_values
    #   @return [::Array<::String>]
    #     Only get facet for the given restricted values. Only supported on
    #     textual fields. For example, suppose "category" has three values
    #     "Action > 2022", "Action > 2021" and "Sci-Fi > 2022". If set
    #     "restricted_values" to "Action > 2022", the "category" facet only
    #     contains "Action > 2022". Only supported on textual fields. Maximum
    #     is 10.
    # @!attribute [rw] prefixes
    #   @return [::Array<::String>]
    #     Only get facet values that start with the given string prefix. For
    #     example, suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "prefixes" to "Action", the
    #     "category" facet only contains "Action > 2022" and "Action > 2021".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] contains
    #   @return [::Array<::String>]
    #     Only get facet values that contain the given strings. For example,
    #     suppose "category" has three values "Action > 2022",
    #     "Action > 2021" and "Sci-Fi > 2022". If set "contains" to "2022", the
    #     "category" facet only contains "Action > 2022" and "Sci-Fi > 2022".
    #     Only supported on textual fields. Maximum is 10.
    # @!attribute [rw] case_insensitive
    #   @return [::Boolean]
    #     True to make facet keys case insensitive when getting faceting
    #     values with prefixes or contains; false otherwise.
    # @!attribute [rw] order_by
    #   @return [::String]
    #     The order in which documents are returned.
    #
    #     Allowed values are:
    #
    #     * "count desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#count SearchResponse.Facet.values.count}
    #     descending.
    #
    #     * "value desc", which means order by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::Facet::FacetValue#value SearchResponse.Facet.values.value}
    #     descending.
    #       Only applies to textual facets.
    #
    #     If not set, textual values are sorted in [natural
    #     order](https://en.wikipedia.org/wiki/Natural_sort_order); numerical
    #     intervals are sorted in the order given by
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec::FacetKey#intervals FacetSpec.FacetKey.intervals}.
    class FacetKey
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Boost specification to boost certain documents.
  # @!attribute [rw] condition_boost_specs
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec>]
  #     Condition boost specifications. If a document matches multiple conditions
  #     in the specifications, boost scores from these specifications are all
  #     applied and combined in a non-linear way. Maximum number of
  #     specifications is 20.
  class BoostSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Boost applies to documents which match a condition.
    # @!attribute [rw] condition
    #   @return [::String]
    #     An expression which specifies a boost condition. The syntax and
    #     supported fields are the same as a filter expression. See
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest#filter SearchRequest.filter}
    #     for detail syntax and limitations.
    #
    #     Examples:
    #
    #     * To boost documents with document ID "doc_1" or "doc_2", and
    #     color "Red" or "Blue":
    #     `(document_id: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))`
    # @!attribute [rw] boost
    #   @return [::Float]
    #     Strength of the condition boost, which should be in [-1, 1]. Negative
    #     boost means demotion. Default is 0.0.
    #
    #     Setting to 1.0 gives the document a big promotion. However, it does
    #     not necessarily mean that the boosted document will be the top result
    #     at all times, nor that other documents will be excluded. Results
    #     could still be shown even when none of them matches the condition.
    #     And results that are significantly more relevant to the search query
    #     can still trump your heavily favored but irrelevant documents.
    #
    #     Setting to -1.0 gives the document a big demotion. However, results
    #     that are deeply relevant might still be shown. The document will have
    #     an upstream battle to get a fairly high ranking, but it is not
    #     blocked out completely.
    #
    #     Setting to 0.0 means no boost applied. The boosting condition is
    #     ignored. Only one of the (condition, boost) combination or the
    #     boost_control_spec below are set. If both are set then the global boost
    #     is ignored and the more fine-grained boost_control_spec is applied.
    # @!attribute [rw] boost_control_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec]
    #     Complex specification for custom ranking based on customer defined
    #     attribute value.
    class ConditionBoostSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Specification for custom ranking based on customer specified attribute
      # value. It provides more controls for customized ranking than the simple
      # (condition, boost) combination above.
      # @!attribute [rw] field_name
      #   @return [::String]
      #     The name of the field whose value will be used to determine the
      #     boost amount.
      # @!attribute [rw] attribute_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::AttributeType]
      #     The attribute type to be used to determine the boost amount. The
      #     attribute value can be derived from the field value of the specified
      #     field_name. In the case of numerical it is straightforward i.e.
      #     attribute_value = numerical_field_value. In the case of freshness
      #     however, attribute_value = (time.now() - datetime_field_value).
      # @!attribute [rw] interpolation_type
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::InterpolationType]
      #     The interpolation type to be applied to connect the control points
      #     listed below.
      # @!attribute [rw] control_points
      #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec::ConditionBoostSpec::BoostControlSpec::ControlPoint>]
      #     The control points used to define the curve. The monotonic function
      #     (defined through the interpolation_type above) passes through the
      #     control points listed here.
      class BoostControlSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # The control points used to define the curve. The curve defined
        # through these control points can only be monotonically increasing
        # or decreasing(constant values are acceptable).
        # @!attribute [rw] attribute_value
        #   @return [::String]
        #     Can be one of:
        #     1. The numerical field value.
        #     2. The duration spec for freshness:
        #     The value must be formatted as an XSD `dayTimeDuration` value (a
        #     restricted subset of an ISO 8601 duration value). The pattern for
        #     this is: `[nD][T[nH][nM][nS]]`.
        # @!attribute [rw] boost_amount
        #   @return [::Float]
        #     The value between -1 to 1 by which to boost the score if the
        #     attribute_value evaluates to the value specified above.
        class ControlPoint
          include ::Google::Protobuf::MessageExts
          extend ::Google::Protobuf::MessageExts::ClassMethods
        end

        # The attribute(or function) for which the custom ranking is to be
        # applied.
        module AttributeType
          # Unspecified AttributeType.
          ATTRIBUTE_TYPE_UNSPECIFIED = 0

          # The value of the numerical field will be used to dynamically update
          # the boost amount. In this case, the attribute_value (the x value)
          # of the control point will be the actual value of the numerical
          # field for which the boost_amount is specified.
          NUMERICAL = 1

          # For the freshness use case the attribute value will be the duration
          # between the current time and the date in the datetime field
          # specified. The value must be formatted as an XSD `dayTimeDuration`
          # value (a restricted subset of an ISO 8601 duration value). The
          # pattern for this is: `[nD][T[nH][nM][nS]]`.
          # For example, `5D`, `3DT12H30M`, `T24H`.
          FRESHNESS = 2
        end

        # The interpolation type to be applied. Default will be linear
        # (Piecewise Linear).
        module InterpolationType
          # Interpolation type is unspecified. In this case, it defaults to
          # Linear.
          INTERPOLATION_TYPE_UNSPECIFIED = 0

          # Piecewise linear interpolation will be applied.
          LINEAR = 1
        end
      end
    end
  end

  # Specification to determine under which conditions query expansion should
  # occur.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition]
  #     The condition under which query expansion should occur. Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
  # @!attribute [rw] pin_unexpanded_results
  #   @return [::Boolean]
  #     Whether to pin unexpanded results. If this field is set to true,
  #     unexpanded products are always at the top of the search results, followed
  #     by the expanded results.
  class QueryExpansionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition query expansion should occur.
    module Condition
      # Unspecified query expansion condition. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disabled query expansion. Only the exact search query is used, even if
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#total_size SearchResponse.total_size}
      # is zero.
      DISABLED = 1

      # Automatic query expansion built by the Search API.
      AUTO = 2
    end
  end

  # The specification for query spell correction.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode]
  #     The mode under which spell correction
  #     replaces the original search query. Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
  class SpellCorrectionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which mode spell correction should occur.
    module Mode
      # Unspecified spell correction mode. In this case, server behavior
      # defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Search API tries to find a spelling suggestion. If a suggestion is
      # found, it is put in the
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse#corrected_query SearchResponse.corrected_query}.
      # The spelling suggestion won't be used as the search query.
      SUGGESTION_ONLY = 1

      # Automatic spell correction built by the Search API. Search will
      # be based on the corrected query if found.
      AUTO = 2
    end
  end

  # A specification for configuring the behavior of content search.
  # @!attribute [rw] snippet_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SnippetSpec]
  #     If `snippetSpec` is not specified, snippets are not included in the
  #     search response.
  # @!attribute [rw] summary_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec]
  #     If `summarySpec` is not specified, summaries are not included in the
  #     search response.
  # @!attribute [rw] extractive_content_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ExtractiveContentSpec]
  #     If there is no extractive_content_spec provided, there will be no
  #     extractive answer in the search response.
  # @!attribute [rw] search_result_mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode]
  #     Specifies the search result mode. If unspecified, the
  #     search result mode defaults to `DOCUMENTS`.
  # @!attribute [rw] chunk_spec
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::ChunkSpec]
  #     Specifies the chunk spec to be returned from the search response.
  #     Only available if the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
  class ContentSearchSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # A specification for configuring snippets in a search response.
    # @!attribute [rw] max_snippet_count
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Integer]
    #     [DEPRECATED] This field is deprecated. To control snippet return, use
    #     `return_snippet` field. For backwards compatibility, we will return
    #     snippet if max_snippet_count > 0.
    # @!attribute [rw] reference_only
    #   @deprecated This field is deprecated and may be removed in the next major version update.
    #   @return [::Boolean]
    #     [DEPRECATED] This field is deprecated and will have no affect on the
    #     snippet.
    # @!attribute [rw] return_snippet
    #   @return [::Boolean]
    #     If `true`, then return snippet. If no snippet can be generated, we
    #     return "No snippet is available for this page." A `snippet_status` with
    #     `SUCCESS` or `NO_SNIPPET_AVAILABLE` will also be returned.
    class SnippetSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # A specification for configuring a summary returned in a search
    # response.
    # @!attribute [rw] summary_result_count
    #   @return [::Integer]
    #     The number of top results to generate the summary from. If the number
    #     of results returned is less than `summaryResultCount`, the summary is
    #     generated from all of the results.
    #
    #     At most 10 results for documents mode, or 50 for chunks mode, can be
    #     used to generate a summary. The chunks mode is used when
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    #     is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}.
    # @!attribute [rw] include_citations
    #   @return [::Boolean]
    #     Specifies whether to include citations in the summary. The default
    #     value is `false`.
    #
    #     When this field is set to `true`, summaries include in-line citation
    #     numbers.
    #
    #     Example summary including citations:
    #
    #     BigQuery is Google Cloud's fully managed and completely serverless
    #     enterprise data warehouse [1]. BigQuery supports all data types, works
    #     across clouds, and has built-in machine learning and business
    #     intelligence, all within a unified platform [2, 3].
    #
    #     The citation numbers refer to the returned search results and are
    #     1-indexed. For example, [1] means that the sentence is attributed to
    #     the first search result. [2, 3] means that the sentence is attributed
    #     to both the second and third search results.
    # @!attribute [rw] ignore_adversarial_query
    #   @return [::Boolean]
    #     Specifies whether to filter out adversarial queries. The default value
    #     is `false`.
    #
    #     Google employs search-query classification to detect adversarial
    #     queries. No summary is returned if the search query is classified as an
    #     adversarial query. For example, a user might ask a question regarding
    #     negative comments about the company or submit a query designed to
    #     generate unsafe, policy-violating output. If this field is set to
    #     `true`, we skip generating summaries for adversarial queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_non_summary_seeking_query
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that are not summary-seeking.
    #     The default value is `false`.
    #
    #     Google employs search-query classification to detect summary-seeking
    #     queries. No summary is returned if the search query is classified as a
    #     non-summary seeking query. For example, `why is the sky blue` and `Who
    #     is the best soccer player in the world?` are summary-seeking queries,
    #     but `SFO airport` and `world cup 2026` are not. They are most likely
    #     navigational queries. If this field is set to `true`, we skip
    #     generating summaries for non-summary seeking queries and return
    #     fallback messages instead.
    # @!attribute [rw] ignore_low_relevant_content
    #   @return [::Boolean]
    #     Specifies whether to filter out queries that have low relevance. The
    #     default value is `false`.
    #
    #     If this field is set to `false`, all search results are used regardless
    #     of relevance to generate answers. If set to `true`, only queries with
    #     high relevance search results will generate answers.
    # @!attribute [rw] ignore_jail_breaking_query
    #   @return [::Boolean]
    #     Optional. Specifies whether to filter out jail-breaking queries. The
    #     default value is `false`.
    #
    #     Google employs search-query classification to detect jail-breaking
    #     queries. No summary is returned if the search query is classified as a
    #     jail-breaking query. A user might add instructions to the query to
    #     change the tone, style, language, content of the answer, or ask the
    #     model to act as a different entity, e.g. "Reply in the tone of a
    #     competing company's CEO". If this field is set to `true`, we skip
    #     generating summaries for jail-breaking queries and return fallback
    #     messages instead.
    # @!attribute [rw] multimodal_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec]
    #     Optional. Multimodal specification.
    # @!attribute [rw] model_prompt_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelPromptSpec]
    #     If specified, the spec will be used to modify the prompt provided to
    #     the LLM.
    # @!attribute [rw] language_code
    #   @return [::String]
    #     Language code for Summary. Use language tags defined by
    #     [BCP47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt).
    #     Note: This is an experimental feature.
    # @!attribute [rw] model_spec
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::ModelSpec]
    #     If specified, the spec will be used to modify the model specification
    #     provided to the LLM.
    # @!attribute [rw] use_semantic_chunks
    #   @return [::Boolean]
    #     If true, answer will be generated from most relevant chunks from top
    #     search results. This feature will improve summary quality.
    #     Note that with this feature enabled, not all top search results
    #     will be referenced and included in the reference list, so the citation
    #     source index only points to the search results listed in the reference
    #     list.
    class SummarySpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods

      # Multimodal specification: Will return an image from specified source.
      # If multiple sources are specified, the pick is a quality based
      # decision.
      # @!attribute [rw] image_source
      #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec::MultiModalSpec::ImageSource]
      #     Optional. Source of image returned in the answer.
      class MultiModalSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods

        # Specifies the image source.
        module ImageSource
          # Unspecified image source (multimodal feature is disabled by
          # default).
          IMAGE_SOURCE_UNSPECIFIED = 0

          # Behavior when service determines the pick from all available
          # sources.
          ALL_AVAILABLE_SOURCES = 1

          # Includes image from corpus in the answer.
          CORPUS_IMAGE_ONLY = 2

          # Triggers figure generation in the answer.
          FIGURE_GENERATION_ONLY = 3
        end
      end

      # Specification of the prompt to use with the model.
      # @!attribute [rw] preamble
      #   @return [::String]
      #     Text at the beginning of the prompt that instructs the assistant.
      #     Examples are available in the user guide.
      class ModelPromptSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end

      # Specification of the model.
      # @!attribute [rw] version
      #   @return [::String]
      #     The model version used to generate the summary.
      #
      #     Supported values are:
      #
      #     * `stable`: string. Default value when no value is specified. Uses a
      #        generally available, fine-tuned model. For more information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      #     * `preview`: string. (Public preview) Uses a preview model. For more
      #        information, see
      #        [Answer generation model versions and
      #        lifecycle](https://cloud.google.com/generative-ai-app-builder/docs/answer-generation-models).
      class ModelSpec
        include ::Google::Protobuf::MessageExts
        extend ::Google::Protobuf::MessageExts::ClassMethods
      end
    end

    # A specification for configuring the extractive content in a search
    # response.
    # @!attribute [rw] max_extractive_answer_count
    #   @return [::Integer]
    #     The maximum number of extractive answers returned in each search
    #     result.
    #
    #     An extractive answer is a verbatim answer extracted from the original
    #     document, which provides a precise and contextually relevant answer to
    #     the search query.
    #
    #     If the number of matching answers is less than the
    #     `max_extractive_answer_count`, return all of the answers. Otherwise,
    #     return the `max_extractive_answer_count`.
    #
    #     At most five answers are returned for each
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchResponse::SearchResult SearchResult}.
    # @!attribute [rw] max_extractive_segment_count
    #   @return [::Integer]
    #     The max number of extractive segments returned in each search result.
    #     Only applied if the
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore DataStore} is set to
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore::ContentConfig::CONTENT_REQUIRED DataStore.ContentConfig.CONTENT_REQUIRED}
    #     or
    #     {::Google::Cloud::DiscoveryEngine::V1beta::DataStore#solution_types DataStore.solution_types}
    #     is
    #     {::Google::Cloud::DiscoveryEngine::V1beta::SolutionType::SOLUTION_TYPE_CHAT SOLUTION_TYPE_CHAT}.
    #
    #     An extractive segment is a text segment extracted from the original
    #     document that is relevant to the search query, and, in general, more
    #     verbose than an extractive answer. The segment could then be used as
    #     input for LLMs to generate summaries and answers.
    #
    #     If the number of matching segments is less than
    #     `max_extractive_segment_count`, return all of the segments. Otherwise,
    #     return the `max_extractive_segment_count`.
    # @!attribute [rw] return_extractive_segment_score
    #   @return [::Boolean]
    #     Specifies whether to return the confidence score from the extractive
    #     segments in each search result. This feature is available only for new
    #     or allowlisted data stores. To allowlist your data store,
    #     contact your Customer Engineer. The default value is `false`.
    # @!attribute [rw] num_previous_segments
    #   @return [::Integer]
    #     Specifies whether to also include the adjacent from each selected
    #     segments.
    #     Return at most `num_previous_segments` segments before each selected
    #     segments.
    # @!attribute [rw] num_next_segments
    #   @return [::Integer]
    #     Return at most `num_next_segments` segments after each selected
    #     segments.
    class ExtractiveContentSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the chunk spec to be returned from the search response.
    # Only available if the
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec#search_result_mode SearchRequest.ContentSearchSpec.search_result_mode}
    # is set to
    # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SearchResultMode::CHUNKS CHUNKS}
    # @!attribute [rw] num_previous_chunks
    #   @return [::Integer]
    #     The number of previous chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no previous chunks will be returned.
    # @!attribute [rw] num_next_chunks
    #   @return [::Integer]
    #     The number of next chunks to be returned of the current chunk. The
    #     maximum allowed value is 3.
    #     If not specified, no next chunks will be returned.
    class ChunkSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end

    # Specifies the search result mode. If unspecified, the
    # search result mode defaults to `DOCUMENTS`.
    module SearchResultMode
      # Default value.
      SEARCH_RESULT_MODE_UNSPECIFIED = 0

      # Returns documents in the search result.
      DOCUMENTS = 1

      # Returns chunks in the search result. Only available if the
      # {::Google::Cloud::DiscoveryEngine::V1beta::DocumentProcessingConfig#chunking_config DocumentProcessingConfig.chunking_config}
      # is specified.
      CHUNKS = 2
    end
  end

  # The specification that uses customized query embedding vector to do
  # semantic document retrieval.
  # @!attribute [rw] embedding_vectors
  #   @return [::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec::EmbeddingVector>]
  #     The embedding vector used for retrieval. Limit to 1.
  class EmbeddingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Embedding vector.
    # @!attribute [rw] field_path
    #   @return [::String]
    #     Embedding field path in schema.
    # @!attribute [rw] vector
    #   @return [::Array<::Float>]
    #     Query embedding vector.
    class EmbeddingVector
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # Specification to enable natural language understanding capabilities for
  # search requests.
  # @!attribute [rw] filter_extraction_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition]
  #     The condition under which filter extraction should occur.
  #     Server behavior defaults to `DISABLED`.
  # @!attribute [rw] geo_search_query_detection_field_names
  #   @return [::Array<::String>]
  #     Field names used for location-based filtering, where geolocation filters
  #     are detected in natural language search queries.
  #     Only valid when the FilterExtractionCondition is set to `ENABLED`.
  # @!attribute [rw] extracted_filter_behavior
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::ExtractedFilterBehavior]
  #     Optional. Controls behavior of how extracted filters are applied to the
  #     search. The default behavior depends on the request. For single datastore
  #     structured search, the default is `HARD_FILTER`. For multi-datastore
  #     search, the default behavior is `SOFT_BOOST`.
  #     Location-based filters are always applied as hard filters, and the
  #     `SOFT_BOOST` setting will not affect them.
  #     This field is only used if
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition SearchRequest.NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition}
  #     is set to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec::FilterExtractionCondition::ENABLED FilterExtractionCondition.ENABLED}.
  # @!attribute [rw] allowed_field_names
  #   @return [::Array<::String>]
  #     Optional. Allowlist of fields that can be used for natural language
  #     filter extraction. By default, if this is unspecified, all indexable
  #     fields are eligible for natural language filter extraction (but are not
  #     guaranteed to be used). If any fields are specified in
  #     allowed_field_names, only the fields that are both marked as indexable in
  #     the schema and specified in the allowlist will be eligible for natural
  #     language filter extraction. Note: for multi-datastore search, this is not
  #     yet supported, and will be ignored.
  class NaturalLanguageQueryUnderstandingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition filter extraction should occur.
    module FilterExtractionCondition
      # Server behavior defaults to `DISABLED`.
      CONDITION_UNSPECIFIED = 0

      # Disables NL filter extraction.
      DISABLED = 1

      # Enables NL filter extraction.
      ENABLED = 2
    end

    # Enum describing how extracted filters are applied to the search.
    module ExtractedFilterBehavior
      # `EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED` will use the default behavior
      # for extracted filters. For single datastore search, the default is to
      # apply as hard filters. For multi-datastore search, the default is to
      # apply as soft boosts.
      EXTRACTED_FILTER_BEHAVIOR_UNSPECIFIED = 0

      # Applies all extracted filters as hard filters on the results. Results
      # that do not pass the extracted filters will not be returned in the
      # result set.
      HARD_FILTER = 1

      # Applies all extracted filters as soft boosts. Results that pass the
      # filters will be boosted up to higher ranks in the result set.
      SOFT_BOOST = 2
    end
  end

  # Specification for search as you type in search requests.
  # @!attribute [rw] condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition]
  #     The condition under which search as you type should occur.
  #     Default to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
  class SearchAsYouTypeSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition search as you type should occur.
    module Condition
      # Server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec::Condition::DISABLED Condition.DISABLED}.
      CONDITION_UNSPECIFIED = 0

      # Disables Search As You Type.
      DISABLED = 1

      # Enables Search As You Type.
      ENABLED = 2

      # Automatic switching between search-as-you-type and standard search
      # modes, ideal for single-API implementations (e.g., debouncing).
      AUTO = 3
    end
  end

  # Specifies features for display, like match highlighting.
  # @!attribute [rw] match_highlighting_condition
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec::MatchHighlightingCondition]
  #     The condition under which match highlighting should occur.
  class DisplaySpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing under which condition match highlighting should occur.
    module MatchHighlightingCondition
      # Server behavior is the same as `MATCH_HIGHLIGHTING_DISABLED`.
      MATCH_HIGHLIGHTING_CONDITION_UNSPECIFIED = 0

      # Disables match highlighting on all documents.
      MATCH_HIGHLIGHTING_DISABLED = 1

      # Enables match highlighting on all documents.
      MATCH_HIGHLIGHTING_ENABLED = 2
    end
  end

  # Specification for crowding. Crowding improves the diversity of search
  # results by limiting the number of results that share the same field value.
  # For example, crowding on the color field with a max_count of 3 and mode
  # DROP_CROWDED_RESULTS will return at most 3 results with the same color
  # across all pages.
  # @!attribute [rw] field
  #   @return [::String]
  #     The field to use for crowding. Documents can be crowded by a field in the
  #     {::Google::Cloud::DiscoveryEngine::V1beta::Document Document} object. Crowding
  #     field is case sensitive.
  # @!attribute [rw] max_count
  #   @return [::Integer]
  #     The maximum number of documents to keep per value of the field. Once
  #     there are at least max_count previous results which contain the same
  #     value for the given field (according to the order specified in
  #     `order_by`), later results with the same value are "crowded away".
  #     If not specified, the default value is 1.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode]
  #     Mode to use for documents that are crowded away.
  class CrowdingSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Enum describing the mode to use for documents that are crowded away.
    # They can be dropped or demoted to the later pages.
    module Mode
      # Unspecified crowding mode. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec::Mode::DROP_CROWDED_RESULTS Mode.DROP_CROWDED_RESULTS}.
      MODE_UNSPECIFIED = 0

      # Drop crowded results.
      DROP_CROWDED_RESULTS = 1

      # Demote crowded results to the later pages.
      DEMOTE_CROWDED_RESULTS_TO_END = 2
    end
  end

  # Session specification.
  # @!attribute [rw] query_id
  #   @return [::String]
  #     If set, the search result gets stored to the "turn" specified by this
  #     query ID.
  #
  #     Example: Let's say the session looks like this:
  #       session {
  #         name: ".../sessions/xxx"
  #         turns {
  #           query { text: "What is foo?" query_id: ".../questions/yyy" }
  #           answer: "Foo is ..."
  #         }
  #         turns {
  #           query { text: "How about bar then?" query_id: ".../questions/zzz" }
  #         }
  #       }
  #
  #     The user can call /search API with a request like this:
  #
  #        session: ".../sessions/xxx"
  #        session_spec { query_id: ".../questions/zzz" }
  #
  #     Then, the API stores the search result, associated with the last turn.
  #     The stored search result can be used by a subsequent /answer API call
  #     (with the session ID and the query ID specified). Also, it is possible
  #     to call /search and /answer in parallel with the same session ID & query
  #     ID.
  # @!attribute [rw] search_result_persistence_count
  #   @return [::Integer]
  #     The number of top search results to persist. The persisted search results
  #     can be used for the subsequent /answer api call.
  #
  #     This field is similar to the `summary_result_count` field in
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec::SummarySpec#summary_result_count SearchRequest.ContentSearchSpec.SummarySpec.summary_result_count}.
  #
  #     At most 10 results for documents mode, or 50 for chunks mode.
  class SessionSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Relevance filtering specification.
  # @!attribute [rw] keyword_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for keyword search.
  # @!attribute [rw] semantic_search_threshold
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec::RelevanceThresholdSpec]
  #     Optional. Relevance filtering threshold specification for semantic
  #     search.
  class RelevanceFilterSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # Specification for relevance filtering on a specific sub-search.
    # @!attribute [rw] relevance_threshold
    #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold]
    #     Pre-defined relevance threshold for the sub-search.
    #
    #     Note: The following fields are mutually exclusive: `relevance_threshold`, `semantic_relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    # @!attribute [rw] semantic_relevance_threshold
    #   @return [::Float]
    #     Custom relevance threshold for the sub-search.
    #     The value must be in [0.0, 1.0].
    #
    #     Note: The following fields are mutually exclusive: `semantic_relevance_threshold`, `relevance_threshold`. If a field in that set is populated, all other fields in the set will automatically be cleared.
    class RelevanceThresholdSpec
      include ::Google::Protobuf::MessageExts
      extend ::Google::Protobuf::MessageExts::ClassMethods
    end
  end

  # The specification for personalization.
  # @!attribute [rw] mode
  #   @return [::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode]
  #     The personalization mode of the search request.
  #     Defaults to
  #     {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
  class PersonalizationSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods

    # The personalization mode of each search request.
    module Mode
      # Default value. In this case, server behavior defaults to
      # {::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec::Mode::AUTO Mode.AUTO}.
      MODE_UNSPECIFIED = 0

      # Personalization is enabled if data quality requirements are met.
      AUTO = 1

      # Disable personalization.
      DISABLED = 2
    end
  end

  # The specification for returning the document relevance score.
  # @!attribute [rw] return_relevance_score
  #   @return [::Boolean]
  #     Optional. Whether to return the relevance score for search results.
  #     The higher the score, the more relevant the document is to the query.
  class RelevanceScoreSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # SearchAddonSpec is used to disable add-ons for search as per new
  # repricing model. By default if the SearchAddonSpec is not specified, we
  # consider that the customer wants to enable them wherever applicable.
  # @!attribute [rw] disable_semantic_add_on
  #   @return [::Boolean]
  #     Optional. If true, semantic add-on is disabled. Semantic add-on includes
  #     embeddings and jetstream.
  # @!attribute [rw] disable_kpi_personalization_add_on
  #   @return [::Boolean]
  #     Optional. If true, disables event re-ranking and personalization to
  #     optimize KPIs & personalize results.
  # @!attribute [rw] disable_generative_answer_add_on
  #   @return [::Boolean]
  #     Optional. If true, generative answer add-on is disabled. Generative
  #     answer add-on includes natural language to filters and simple answers.
  class SearchAddonSpec
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # Configuration parameters for the Custom Ranking feature.
  # @!attribute [rw] expressions_to_precompute
  #   @return [::Array<::String>]
  #     Optional. A list of ranking expressions (see `ranking_expression` for the
  #     syntax documentation) to evaluate. The evaluation results will be
  #     returned in
  #     `SearchResponse.SearchResult.rank_signals.precomputed_expression_values`
  #     field.
  class CustomRankingParams
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::Google::Protobuf::Value]
  class ParamsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # @!attribute [rw] key
  #   @return [::String]
  # @!attribute [rw] value
  #   @return [::String]
  class UserLabelsEntry
    include ::Google::Protobuf::MessageExts
    extend ::Google::Protobuf::MessageExts::ClassMethods
  end

  # The backend to use for the ranking expression evaluation.
  module RankingExpressionBackend
    # Default option for unspecified/unknown values.
    RANKING_EXPRESSION_BACKEND_UNSPECIFIED = 0

    # Deprecated: Use `RANK_BY_EMBEDDING` instead.
    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression. Legacy enum option, `RANK_BY_EMBEDDING` should be
    # used instead.
    BYOE = 1

    # Deprecated: Use `RANK_BY_FORMULA` instead.
    # Ranking by custom formula. Legacy enum option, `RANK_BY_FORMULA` should
    # be used instead.
    CLEARBOX = 2

    # Ranking by custom embedding model, the default way to evaluate the
    # ranking expression.
    RANK_BY_EMBEDDING = 3

    # Ranking by custom formula.
    RANK_BY_FORMULA = 4
  end

  # The relevance threshold of the search results. The higher relevance
  # threshold is, the higher relevant results are shown and the less number of
  # results are returned.
  module RelevanceThreshold
    # Default value. In this case, server behavior defaults to Google defined
    # threshold.
    RELEVANCE_THRESHOLD_UNSPECIFIED = 0

    # Lowest relevance threshold.
    LOWEST = 1

    # Low relevance threshold.
    LOW = 2

    # Medium relevance threshold.
    MEDIUM = 3

    # High relevance threshold.
    HIGH = 4
  end
end

Class: Google::Cloud::DiscoveryEngine::V1beta::SearchRequest

Overview

Defined Under Namespace

Instance Attribute Summary collapse

Instance Attribute Details

#boost_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec

#branch ⇒ ::String

#canonical_filter ⇒ ::String

#content_search_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec

#crowding_specs ⇒ ::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec>

#custom_ranking_params ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CustomRankingParams

#data_store_specs ⇒ ::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DataStoreSpec>

#display_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec

#embedding_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec

#entity ⇒ ::String

#facet_specs ⇒ ::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec>

#filter ⇒ ::String

#image_query ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ImageQuery

#language_code ⇒ ::String

#natural_language_query_understanding_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec

#num_results_per_data_store ⇒ ::Integer

#offset ⇒ ::Integer

#one_box_page_size ⇒ ::Integer

#order_by ⇒ ::String

#page_categories ⇒ ::Array<::String>

#page_size ⇒ ::Integer

#page_token ⇒ ::String

#params ⇒ ::Google::Protobuf::Map{::String => ::Google::Protobuf::Value}

#personalization_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec

#query ⇒ ::String

#query_expansion_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec

#ranking_expression ⇒ ::String

#ranking_expression_backend ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RankingExpressionBackend

#region_code ⇒ ::String

#relevance_filter_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec

#relevance_score_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceScoreSpec

#relevance_threshold ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold

#safe_search ⇒ ::Boolean

#search_addon_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAddonSpec

#search_as_you_type_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec

#serving_config ⇒ ::String

#session ⇒ ::String

#session_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SessionSpec

#spell_correction_spec ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec

#user_info ⇒ ::Google::Cloud::DiscoveryEngine::V1beta::UserInfo

#user_labels ⇒ ::Google::Protobuf::Map{::String => ::String}

#user_pseudo_id ⇒ ::String

#boost_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::BoostSpec`

#branch ⇒ `::String`

#canonical_filter ⇒ `::String`

#content_search_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ContentSearchSpec`

#crowding_specs ⇒ `::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CrowdingSpec>`

#custom_ranking_params ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::CustomRankingParams`

#data_store_specs ⇒ `::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DataStoreSpec>`

#display_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::DisplaySpec`

#embedding_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::EmbeddingSpec`

#entity ⇒ `::String`

#facet_specs ⇒ `::Array<::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::FacetSpec>`

#filter ⇒ `::String`

#image_query ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::ImageQuery`

#language_code ⇒ `::String`

#natural_language_query_understanding_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::NaturalLanguageQueryUnderstandingSpec`

#num_results_per_data_store ⇒ `::Integer`

#offset ⇒ `::Integer`

#one_box_page_size ⇒ `::Integer`

#order_by ⇒ `::String`

#page_categories ⇒ `::Array<::String>`

#page_size ⇒ `::Integer`

#page_token ⇒ `::String`

#params ⇒ `::Google::Protobuf::Map{::String => ::Google::Protobuf::Value}`

#personalization_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::PersonalizationSpec`

#query ⇒ `::String`

#query_expansion_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::QueryExpansionSpec`

#ranking_expression ⇒ `::String`

#ranking_expression_backend ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RankingExpressionBackend`

#region_code ⇒ `::String`

#relevance_filter_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceFilterSpec`

#relevance_score_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceScoreSpec`

#relevance_threshold ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::RelevanceThreshold`

#safe_search ⇒ `::Boolean`

#search_addon_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAddonSpec`

#search_as_you_type_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SearchAsYouTypeSpec`

#serving_config ⇒ `::String`

#session ⇒ `::String`

#session_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SessionSpec`

#spell_correction_spec ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::SearchRequest::SpellCorrectionSpec`

#user_info ⇒ `::Google::Cloud::DiscoveryEngine::V1beta::UserInfo`

#user_labels ⇒ `::Google::Protobuf::Map{::String => ::String}`

#user_pseudo_id ⇒ `::String`