Class: Safire::Protocols::SmartMetadata

Inherits:
Entity
  • Object
show all
Defined in:
lib/safire/protocols/smart_metadata.rb

Overview

SMART Metadata obtained from SMART discovery endpoint. Attributes are defined as per SMART App Launch specification

Constant Summary collapse

REQUIRED_ATTRIBUTES = 
%i[
  grant_types_supported token_endpoint capabilities
  code_challenge_methods_supported
].freeze
OPTIONAL_ATTRIBUTES = 
%i[
  issuer
  jwks_uri
  authorization_endpoint
  token_endpoint_auth_methods_supported
  token_endpoint_auth_signing_alg_values_supported
  registration_endpoint
  associated_endpoints
  user_access_brand_bundle
  user_access_brand_identifier
  scopes_supported
  response_types_supported
  management_endpoint
  introspection_endpoint
  revocation_endpoint
].freeze
ATTRIBUTES = 
(REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze
SUPPORTED_ASYMMETRIC_ALGORITHMS =

Supported asymmetric signing algorithms (required by SMART spec)

%w[RS384 ES384].freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Entity

#to_hash

Constructor Details

#initialize(metadata) ⇒ SmartMetadata

Returns a new instance of SmartMetadata.



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# File 'lib/safire/protocols/smart_metadata.rb', line 94

def initialize(metadata)
  super(metadata, ATTRIBUTES)
end

Instance Attribute Details

#associated_endpoints ⇒ Array<Hash> (readonly)

Returns list of objects for endpoints that share the same authorization mechanism as this FHIR endpoint, each with a “url” and “capabilities” array. Optionally provided.

Returns:

  • (Array<Hash>) —

    list of objects for endpoints that share the same authorization mechanism as this FHIR endpoint, each with a “url” and “capabilities” array. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#authorization_endpoint ⇒ String (readonly)

Returns URL of the server’s OAuth2 Authorization Endpoint. Required if the server’s capabilities include launch-standalone or launch-ehr-launch.

Returns:

  • (String) —

    URL of the server’s OAuth2 Authorization Endpoint. Required if the server’s capabilities include launch-standalone or launch-ehr-launch.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#capabilities ⇒ Array<String> (readonly)

Returns list of SMART capabilities supported by the server.

Returns:

  • (Array<String>) —

    list of SMART capabilities supported by the server.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#code_challenge_methods_supported ⇒ Array<String> (readonly)

Returns list of PKCE code challenge methods supported. Should include "S256". Should not include "plain". See #valid? for compliance checks.

Returns:

  • (Array<String>) —

    list of PKCE code challenge methods supported. Should include "S256". Should not include "plain". See #valid? for compliance checks.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#grant_types_supported ⇒ Array<String> (readonly)

Returns list of OAuth2 grant types supported at the token endpoint.

Returns:

  • (Array<String>) —

    list of OAuth2 grant types supported at the token endpoint.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#introspection_endpoint ⇒ String (readonly)

Returns URL to a server’s introspection endpoint that can be used to validate a token. Optionally provided.

Returns:

  • (String) —

    URL to a server’s introspection endpoint that can be used to validate a token. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#issuer ⇒ String (readonly)

Returns conveying this system’s OpenID Connect Issuer URL. Required if the server’s capabilities include sso-openid-connect.

Returns:

  • (String) —

    conveying this system’s OpenID Connect Issuer URL. Required if the server’s capabilities include sso-openid-connect.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#jwks_uri ⇒ String (readonly)

Returns URL of the server’s JSON Web Key Set endpoint. Required if the server’s capabilities include sso-openid-connect.

Returns:

  • (String) —

    URL of the server’s JSON Web Key Set endpoint. Required if the server’s capabilities include sso-openid-connect.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#management_endpoint ⇒ String (readonly)

Returns URL where an end-user can view which applications currently have access to data and can make adjustments to these access rights. Optionally provided.

Returns:

  • (String) —

    URL where an end-user can view which applications currently have access to data and can make adjustments to these access rights. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#registration_endpoint ⇒ String (readonly)

Returns URL of the server’s OAuth2 Dynamic Client Registration Endpoint. Optionally provided.

Returns:

  • (String) —

    URL of the server’s OAuth2 Dynamic Client Registration Endpoint. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#response_types_supported ⇒ Array<String> (readonly)

Returns list of OAuth2 response types supported. Optionally provided.

Returns:

  • (Array<String>) —

    list of OAuth2 response types supported. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#revocation_endpoint ⇒ String (readonly)

Returns URL to a server’s revocation endpoint that can be used to revoke a token. Optionally provided.

Returns:

  • (String) —

    URL to a server’s revocation endpoint that can be used to revoke a token. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#scopes_supported ⇒ Array<String> (readonly)

Returns list of scopes a client may request. Optionally provided.

Returns:

  • (Array<String>) —

    list of scopes a client may request. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#token_endpoint ⇒ String (readonly)

Returns URL of the server’s OAuth2 Token Endpoint.

Returns:

  • (String) —

    URL of the server’s OAuth2 Token Endpoint.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#token_endpoint_auth_methods_supported ⇒ Array<String> (readonly)

Returns list of client authentication methods supported at the token endpoint. Optionally provided.

Returns:

  • (Array<String>) —

    list of client authentication methods supported at the token endpoint. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#token_endpoint_auth_signing_alg_values_supported ⇒ Array<String> (readonly)

Returns list of signing algorithms supported for JWT-based client authentication. Optionally provided. Used for confidential asymmetric authentication.

Returns:

  • (Array<String>) —

    list of signing algorithms supported for JWT-based client authentication. Optionally provided. Used for confidential asymmetric authentication.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#user_access_brand_bundle ⇒ String (readonly)

Returns URL for a Brand Bundle for user-facing applications. Optionally provided.

Returns:

  • (String) —

    URL for a Brand Bundle for user-facing applications. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

#user_access_brand_identifier ⇒ String (readonly)

Returns Identifier for the primary entry in a Brand Bundle. Optionally provided.

Returns:

  • (String) —

    Identifier for the primary entry in a Brand Bundle. Optionally provided.



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# File 'lib/safire/protocols/smart_metadata.rb', line 52

class SmartMetadata < Safire::Entity
  REQUIRED_ATTRIBUTES = %i[
    grant_types_supported token_endpoint capabilities
    code_challenge_methods_supported
  ].freeze

  OPTIONAL_ATTRIBUTES = %i[
    issuer
    jwks_uri
    authorization_endpoint
    token_endpoint_auth_methods_supported
    token_endpoint_auth_signing_alg_values_supported
    registration_endpoint
    associated_endpoints
    user_access_brand_bundle
    user_access_brand_identifier
    scopes_supported
    response_types_supported
    management_endpoint
    introspection_endpoint
    revocation_endpoint
  ].freeze

  ATTRIBUTES = (REQUIRED_ATTRIBUTES | OPTIONAL_ATTRIBUTES).freeze

  ARRAY_ATTRIBUTE_ELEMENT_TYPES = {
    grant_types_supported: String,
    token_endpoint_auth_methods_supported: String,
    token_endpoint_auth_signing_alg_values_supported: String,
    associated_endpoints: Hash,
    scopes_supported: String,
    response_types_supported: String,
    capabilities: String,
    code_challenge_methods_supported: String
  }.freeze
  private_constant :ARRAY_ATTRIBUTE_ELEMENT_TYPES

  # Supported asymmetric signing algorithms (required by SMART spec)
  SUPPORTED_ASYMMETRIC_ALGORITHMS = %w[RS384 ES384].freeze

  attr_reader(*ATTRIBUTES)

  def initialize(metadata)
    super(metadata, ATTRIBUTES)
  end

  # Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.
  #
  # This is a user-callable helper. Safire performs discovery without automatically
  # asserting server compliance — it is the caller's responsibility to invoke this
  # method when they wish to inspect these conformance signals. This helper is
  # not a complete server certification suite.
  #
  # Checks performed:
  # - All required fields are present
  #   (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  # - Conditional fields present when their capability is advertised
  #   (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  # - Array-valued fields are arrays containing values of the documented type
  # - `code_challenge_methods_supported` includes 'S256'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  # - `code_challenge_methods_supported` does NOT include 'plain'
  #   (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)
  #
  # A warning is logged for each SMART 2.2.0 violation detected.
  #
  # @return [Boolean] true if all checks pass, false if any violation is found
  def valid?
    required_attrs = [*REQUIRED_ATTRIBUTES]
    required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
    required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

    missing_attrs = required_attrs.reject { |attr| public_send(attr) }
    missing_attrs.each do |attr|
      Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
    end

    array_fields_valid = validate_array_fields!
    pkce_valid = validate_pkce_methods!

    missing_attrs.empty? && array_fields_valid && pkce_valid
  end

  # Launch type support checks - requires both capability and authorization_endpoint

  def supports_ehr_launch?
    ehr_launch_capability? && authorization_endpoint.present?
  end

  def supports_standalone_launch?
    standalone_launch_capability? && authorization_endpoint.present?
  end

  # Authentication type support checks

  # Checks if the server supports public client authentication.
  # @return [Boolean] true if server has client-public capability
  def supports_public_auth?
    capability?('client-public')
  end

  # Checks if the server supports confidential symmetric authentication.
  # @return [Boolean] true if server has capability and auth methods not advertised or includes client_secret_basic
  def supports_symmetric_auth?
    capability?('client-confidential-symmetric') &&
      auth_method_supported?('client_secret_basic')
  end

  # Checks if the server supports the SMART Backend Services workflow.
  # @return [Boolean] true if the server advertises the client_credentials grant type
  #   and supports private_key_jwt authentication (via {#supports_asymmetric_auth?})
  def supports_backend_services?
    array_includes?(:grant_types_supported, 'client_credentials') &&
      supports_asymmetric_auth?
  end

  # Checks if the server supports confidential asymmetric authentication.
  # @return [Boolean] true if server has capability, auth methods not advertised or includes private_key_jwt,
  #   and has supported algorithms
  def supports_asymmetric_auth?
    capability?('client-confidential-asymmetric') &&
      auth_method_supported?('private_key_jwt') &&
      asymmetric_signing_algorithms_supported.any?
  end

  # Returns the asymmetric signing algorithms supported by both client and server.
  # If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).
  # @return [Array<String>] list of supported algorithms
  def asymmetric_signing_algorithms_supported
    server_algs = token_endpoint_auth_signing_alg_values_supported
    return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
    return [] unless array_of?(server_algs, String)

    server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
  end

  # Feature support checks

  # Checks whether the server supports Dynamic Client Registration (RFC 7591).
  # @return [Boolean] true if the server advertises a +registration_endpoint+
  def supports_dynamic_registration?
    registration_endpoint.present?
  end

  def supports_post_based_authorization?
    capability?('authorize-post')
  end

  def supports_openid_connect?
    openid_connect_capability? && issuer.present? && jwks_uri.present?
  end

  # Capability-only checks (does not verify required fields are present)

  def ehr_launch_capability?
    capability?('launch-ehr')
  end

  def standalone_launch_capability?
    capability?('launch-standalone')
  end

  def openid_connect_capability?
    capability?('sso-openid-connect')
  end

  private

  def capability?(name)
    array_includes?(:capabilities, name)
  end

  def array_includes?(attribute, value)
    values = public_send(attribute)
    array_of?(values, String) && values.include?(value)
  end

  def auth_method_supported?(method)
    methods = token_endpoint_auth_methods_supported
    methods.nil? || methods == [] || array_includes?(:token_endpoint_auth_methods_supported, method)
  end

  def validate_array_fields!
    valid = true

    ARRAY_ATTRIBUTE_ELEMENT_TYPES.each do |attribute, element_type|
      value = public_send(attribute)
      next if value.nil?
      next if array_of?(value, element_type)

      Safire.logger.warn(
        "SMART metadata non-compliance: field '#{attribute}' must be an array containing only " \
        "#{element_type == Hash ? 'objects' : 'strings'}"
      )
      valid = false
    end

    valid
  end

  def array_of?(value, element_type)
    value.is_a?(Array) && value.all?(element_type)
  end

  def issuer_and_jwks_uri_required?
    openid_connect_capability?
  end

  def authorization_endpoint_required?
    ehr_launch_capability? || standalone_launch_capability?
  end

  # Validates PKCE code challenge methods per SMART App Launch 2.2.0:
  # - 'S256' SHALL be included
  # - 'plain' SHALL NOT be included
  #
  # @return [Boolean] true if both conditions are satisfied
  def validate_pkce_methods!
    valid = true

    unless array_includes?(:code_challenge_methods_supported, 'S256')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'S256' is missing from code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 requires S256)'
      )
      valid = false
    end

    if array_includes?(:code_challenge_methods_supported, 'plain')
      Safire.logger.warn(
        "SMART metadata non-compliance: 'plain' is present in code_challenge_methods_supported " \
        '(SMART App Launch 2.2.0 prohibits plain)'
      )
      valid = false
    end

    valid
  end
end

Instance Method Details

#asymmetric_signing_algorithms_supported ⇒ Array<String>

Returns the asymmetric signing algorithms supported by both client and server. If the server doesn't advertise algorithms, assumes it supports the required ones (RS384, ES384).

Returns:

  • (Array<String>) —

    list of supported algorithms



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# File 'lib/safire/protocols/smart_metadata.rb', line 180

def asymmetric_signing_algorithms_supported
  server_algs = token_endpoint_auth_signing_alg_values_supported
  return SUPPORTED_ASYMMETRIC_ALGORITHMS.dup if server_algs.nil? || server_algs == []
  return [] unless array_of?(server_algs, String)

  server_algs & SUPPORTED_ASYMMETRIC_ALGORITHMS
end

#ehr_launch_capability? ⇒ Boolean

Capability-only checks (does not verify required fields are present)

Returns:

  • (Boolean) 


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# File 'lib/safire/protocols/smart_metadata.rb', line 206

def ehr_launch_capability?
  capability?('launch-ehr')
end

#openid_connect_capability? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/safire/protocols/smart_metadata.rb', line 214

def openid_connect_capability?
  capability?('sso-openid-connect')
end

#standalone_launch_capability? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/safire/protocols/smart_metadata.rb', line 210

def standalone_launch_capability?
  capability?('launch-standalone')
end

#supports_asymmetric_auth? ⇒ Boolean

Checks if the server supports confidential asymmetric authentication.

Returns:

  • (Boolean) —

    true if server has capability, auth methods not advertised or includes private_key_jwt, and has supported algorithms



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# File 'lib/safire/protocols/smart_metadata.rb', line 171

def supports_asymmetric_auth?
  capability?('client-confidential-asymmetric') &&
    auth_method_supported?('private_key_jwt') &&
    asymmetric_signing_algorithms_supported.any?
end

#supports_backend_services? ⇒ Boolean

Checks if the server supports the SMART Backend Services workflow.

Returns:

  • (Boolean) —

    true if the server advertises the client_credentials grant type and supports private_key_jwt authentication (via #supports_asymmetric_auth?)



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# File 'lib/safire/protocols/smart_metadata.rb', line 163

def supports_backend_services?
  array_includes?(:grant_types_supported, 'client_credentials') &&
    supports_asymmetric_auth?
end

#supports_dynamic_registration? ⇒ Boolean

Checks whether the server supports Dynamic Client Registration (RFC 7591).

Returns:

  • (Boolean) —

    true if the server advertises a registration_endpoint



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# File 'lib/safire/protocols/smart_metadata.rb', line 192

def supports_dynamic_registration?
  registration_endpoint.present?
end

#supports_ehr_launch? ⇒ Boolean

Launch type support checks - requires both capability and authorization_endpoint

Returns:

  • (Boolean) 


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# File 'lib/safire/protocols/smart_metadata.rb', line 137

def supports_ehr_launch?
  ehr_launch_capability? && authorization_endpoint.present?
end

#supports_openid_connect? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/safire/protocols/smart_metadata.rb', line 200

def supports_openid_connect?
  openid_connect_capability? && issuer.present? && jwks_uri.present?
end

#supports_post_based_authorization? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/safire/protocols/smart_metadata.rb', line 196

def supports_post_based_authorization?
  capability?('authorize-post')
end

#supports_public_auth? ⇒ Boolean

Checks if the server supports public client authentication.

Returns:

  • (Boolean) —

    true if server has client-public capability



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# File 'lib/safire/protocols/smart_metadata.rb', line 149

def supports_public_auth?
  capability?('client-public')
end

#supports_standalone_launch? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/safire/protocols/smart_metadata.rb', line 141

def supports_standalone_launch?
  standalone_launch_capability? && authorization_endpoint.present?
end

#supports_symmetric_auth? ⇒ Boolean

Checks if the server supports confidential symmetric authentication.

Returns:

  • (Boolean) —

    true if server has capability and auth methods not advertised or includes client_secret_basic



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# File 'lib/safire/protocols/smart_metadata.rb', line 155

def supports_symmetric_auth?
  capability?('client-confidential-symmetric') &&
    auth_method_supported?('client_secret_basic')
end

#valid? ⇒ Boolean

Runs Safire's selected SMART App Launch 2.2.0 structural diagnostics.

This is a user-callable helper. Safire performs discovery without automatically asserting server compliance — it is the caller's responsibility to invoke this method when they wish to inspect these conformance signals. This helper is not a complete server certification suite.

Checks performed:

  • All required fields are present (token_endpoint, grant_types_supported, capabilities, code_challenge_methods_supported)
  • Conditional fields present when their capability is advertised (issuer + jwks_uri for sso-openid-connect; authorization_endpoint for launch types)
  • Array-valued fields are arrays containing values of the documented type
  • code_challenge_methods_supported includes 'S256' (SMART App Launch 2.2.0, §Conformance — SHALL be included)
  • code_challenge_methods_supported does NOT include 'plain' (SMART App Launch 2.2.0, §Conformance — SHALL NOT be included)

A warning is logged for each SMART 2.2.0 violation detected.

Returns:

  • (Boolean) —

    true if all checks pass, false if any violation is found



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# File 'lib/safire/protocols/smart_metadata.rb', line 119

def valid?
  required_attrs = [*REQUIRED_ATTRIBUTES]
  required_attrs.push(:issuer, :jwks_uri) if issuer_and_jwks_uri_required?
  required_attrs.push(:authorization_endpoint) if authorization_endpoint_required?

  missing_attrs = required_attrs.reject { |attr| public_send(attr) }
  missing_attrs.each do |attr|
    Safire.logger.warn("SMART metadata non-compliance: required field '#{attr}' is missing")
  end

  array_fields_valid = validate_array_fields!
  pkce_valid = validate_pkce_methods!

  missing_attrs.empty? && array_fields_valid && pkce_valid
end