Class: ForestAdminDatasourceGraphqlHasura::Introspection::Introspector

Inherits:
Object
  • Object
show all
Defined in:
lib/forest_admin_datasource_graphql_hasura/introspection/introspector.rb

Overview

Builds the datasource structure from the GraphQL introspection query (tables, columns, relationship fields) and the Hasura metadata API (relationship column mappings), when the latter is reachable.

Constant Summary collapse

INTROSPECTION_QUERY = 
<<~GRAPHQL.freeze
  query IntrospectSchema {
    __schema {
      types {
        name
        kind
        fields {
          name
          type { ...TypeRef }
        }
        enumValues { name }
      }
      queryType {
        name
        fields {
          name
          type { ...TypeRef }
          args {
            name
            type { name kind ofType { name kind } }
          }
        }
      }
    }
  }
  fragment TypeRef on __Type {
    name
    kind
    ofType {
      name
      kind
      ofType {
        name
        kind
        ofType { name kind }
      }
    }
  }
GRAPHQL
SCALAR_TYPES = 
%w[
  Int Float String Boolean ID
  uuid timestamptz timestamp date time timetz jsonb json numeric bigint smallint
  integer real double_precision text varchar char bpchar bytea inet cidr macaddr
  money interval bit xml citext
  _text _int4 _uuid _jsonb
].to_set.freeze
TEXT_TYPES =

A Postgres enum, or any scalar Hasura exposes under a custom name (macaddr, a domain type…), displays as a string but has no _like/_ilike in its comparison expression.

%w[String ID text varchar char bpchar citext bytea].to_set.freeze
EXCLUDED_PREFIXES = 
%w[__ hdb_ pg_ information_schema].freeze

Instance Method Summary collapse

Constructor Details

#initialize(client, configuration) ⇒ Introspector

Returns a new instance of Introspector.



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# File 'lib/forest_admin_datasource_graphql_hasura/introspection/introspector.rb', line 64

def initialize(client, configuration)
  @client = client
  @configuration = configuration
end

Instance Method Details

#introspect ⇒ Array<Table>

Returns:



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# File 'lib/forest_admin_datasource_graphql_hasura/introspection/introspector.rb', line 70

def introspect
  types, query_fields = introspection_payload
  metadata = @client.fetch_metadata

  @type_map = build_type_map(types)
  @custom_root_fields = {}
  @relationship_mappings = metadata ? safe_relationship_mappings(metadata) : {}
  @primary_keys = parse_primary_keys(query_fields)

  parse_tables(query_fields)
end