Class: GraphQL::Schema::RelayClassicMutation

Inherits:
Mutation show all
Defined in:
lib/graphql/schema/relay_classic_mutation.rb

Overview

Mutations that extend this base class get some conventions added for free:

  • An argument called clientMutationId is always added, but it’s not passed to the resolve method. The value is re-inserted to the response. (It’s for client libraries to manage optimistic updates.)
  • The returned object type always has a field called clientMutationId to support that.
  • The mutation accepts one argument called input, arguments defined in the mutation class are added to that input object, which is generated by the mutation.

These conventions were first specified by Relay Classic, but they come in handy:

  • clientMutationId supports optimistic updates and cache rollbacks on the client
  • using a single input: argument makes it easy to post whole JSON objects to the mutation using one GraphQL variable ($input) instead of making a separate variable for each argument.

See Also:

  • for an example, it's basically the same.

Constant Summary

Constants included from Member::GraphQLTypeNames

Member::GraphQLTypeNames::Boolean, Member::GraphQLTypeNames::ID, Member::GraphQLTypeNames::Int

Instance Attribute Summary

Attributes inherited from Resolver

#context, #object

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Mutation

field, visible?

Methods included from GraphQL::Schema::Resolver::HasPayloadType

#field_class, #object_class, #payload_type

Methods included from Member::HasFields

#add_field, #field, #field_class, #fields, #get_field, #global_id_field, #own_fields

Methods inherited from Resolver

argument, arguments_loads_as_type, #authorized?, complexity, extras, #initialize, null, #ready?, #resolve, resolve_method, type, type_expr

Methods included from Member::HasPath

#path

Methods included from Member::HasArguments

#add_argument, #argument, #argument_class, #argument_with_loads, #arguments, #own_arguments

Methods included from Member::BaseDSLMethods

#accessible?, #authorized?, #default_graphql_name, #description, #graphql_name, #introspection, #introspection?, #mutation, #name, #overridden_graphql_name, #to_graphql, #visible?

Constructor Details

This class inherits a constructor from GraphQL::Schema::Resolver

Class Method Details

.field_options ⇒ Object

Extend Schema::Mutation.field_options to add the input argument



96
97
98
99
100
101
102
 
# File 'lib/graphql/schema/relay_classic_mutation.rb', line 96

def field_options
  sig = super
  # Arguments were added at the root, but they should be nested
  sig[:arguments].clear
  sig[:arguments][:input] = { type: input_type, required: true }
  sig
end

.input_object_class(new_class = nil) ⇒ Class

The base class for generated input object types

Parameters:

  • new_class (Class) (defaults to: nil) —

    The base class to use for generating input object definitions

Returns:

  • (Class) —

    The base class for this mutation’s generated input object (default is InputObject)



79
80
81
82
83
84
 
# File 'lib/graphql/schema/relay_classic_mutation.rb', line 79

def input_object_class(new_class = nil)
  if new_class
    @input_object_class = new_class
  end
  @input_object_class || (superclass.respond_to?(:input_object_class) ? superclass.input_object_class : GraphQL::Schema::InputObject)
end

.input_type(new_input_type = nil) ⇒ Class

Returns The generated InputObject class for this mutation’s input

Parameters:

  • new_input_type (Class, nil) (defaults to: nil) —

    If provided, it configures this mutation to accept new_input_type instead of generating an input type

Returns:

  • (Class) —

    The generated InputObject class for this mutation’s input



88
89
90
91
92
93
 
# File 'lib/graphql/schema/relay_classic_mutation.rb', line 88

def input_type(new_input_type = nil)
  if new_input_type
    @input_type = new_input_type
  end
  @input_type ||= generate_input_type
end

Instance Method Details

#resolve_with_support(**inputs) ⇒ Object

Override GraphQL::Schema::Resolver#resolve_with_support to delete client_mutation_id from the kwargs.



31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
 
# File 'lib/graphql/schema/relay_classic_mutation.rb', line 31

def resolve_with_support(**inputs)
  # Without the interpreter, the inputs are unwrapped by an instrumenter.
  # But when using the interpreter, no instrumenters are applied.
  if context.interpreter?
    input = inputs[:input].to_h
    # Transfer these from the top-level hash to the
    # shortcutted `input:` object
    self.class.extras.each do |ext|
      input[ext] = inputs[ext]
    end
  else
    input = inputs
  end

  if input
    # This is handled by Relay::Mutation::Resolve, a bit hacky, but here we are.
    input_kwargs = input.to_h
    client_mutation_id = input_kwargs.delete(:client_mutation_id)
  else
    # Relay Classic Mutations with no `argument`s
    # don't require `input:`
    input_kwargs = {}
  end

  return_value = if input_kwargs.any?
    super(input_kwargs)
  else
    super()
  end

  # Again, this is done by an instrumenter when using non-interpreter execution.
  if context.interpreter?
    context.schema.after_lazy(return_value) do |return_hash|
      # It might be an error
      if return_hash.is_a?(Hash)
        return_hash[:client_mutation_id] = client_mutation_id
      end
      return_hash
    end
  else
    return_value
  end
end