Class: GraphQL::Schema::PossibleTypes

Inherits:
Object
  • Object
show all
Defined in:
lib/graphql/schema/possible_types.rb

Overview

Find the members of a union or interface within a given schema.

(Although its members never change, unions are handled this way to simplify execution code.)

Internally, the calculation is cached. It’s assumed that schema members don’t change after creating the schema!

Examples:

Get an interface’s possible types

possible_types = GraphQL::Schema::PossibleTypes(MySchema)
possible_types.possible_types(MyInterface)
# => [MyObjectType, MyOtherObjectType]

Instance Method Summary collapse

Constructor Details

#initialize(schema) ⇒ PossibleTypes

Returns a new instance of PossibleTypes



15
16
17
18
19
20
21
 
# File 'lib/graphql/schema/possible_types.rb', line 15

def initialize(schema)
  @object_types = schema.types.values.select { |type| type.kind.object? }

  @interface_implementers = Hash.new do |hash, key|
    hash[key] = @object_types.select { |type| type.interfaces.include?(key) }.sort_by(&:name)
  end
end

Instance Method Details

#possible_types(type_defn) ⇒ Object 



23
24
25
26
27
28
29
30
31
32
33
34
35
36
 
# File 'lib/graphql/schema/possible_types.rb', line 23

def possible_types(type_defn)
  case type_defn
  when Module
    possible_types(type_defn.graphql_definition)
  when GraphQL::UnionType
    type_defn.possible_types
  when GraphQL::InterfaceType
    @interface_implementers[type_defn]
  when GraphQL::BaseType
    [type_defn]
  else
    raise "Unexpected possible_types object: #{type_defn.inspect}"
  end
end