Class: GraphQL::Schema::Field

Inherits:
Object
  • Object
show all
Extended by:
FindInheritedValue
Includes:
GraphQL::Schema::FindInheritedValue::EmptyObjects, Member::HasArguments, Member::HasAstNode, Member::HasDeprecationReason, Member::HasDirectives, Member::HasPath, Member::HasValidators
Defined in:
lib/graphql/schema/field.rb,
lib/graphql/schema/field/scope_extension.rb,
lib/graphql/schema/field/connection_extension.rb

Defined Under Namespace

Classes: ConnectionExtension, FieldImplementationFailed, MissingReturnTypeError, ScopeExtension

Constant Summary

Constants included from Member::HasDirectives

Member::HasDirectives::NO_DIRECTIVES

Constants included from GraphQL::Schema::FindInheritedValue::EmptyObjects

GraphQL::Schema::FindInheritedValue::EmptyObjects::EMPTY_ARRAY, GraphQL::Schema::FindInheritedValue::EmptyObjects::EMPTY_HASH

Constants included from Member::HasArguments

Member::HasArguments::NO_ARGUMENTS

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Member::HasDeprecationReason

#deprecation_reason, #deprecation_reason=

Methods included from Member::HasDirectives

add_directive, #directive, #directives, get_directives, #remove_directive, remove_directive

Methods included from Member::HasValidators

#validates, #validators

Methods included from Member::HasPath

#path

Methods included from Member::HasAstNode

#ast_node

Methods included from Member::HasArguments

#add_argument, #all_argument_definitions, #argument, #argument_class, #arguments, #arguments_statically_coercible?, #coerce_arguments, #get_argument, #own_arguments, #remove_argument, #validate_directive_argument

Constructor Details

#initialize(type: nil, name: nil, owner: nil, null: nil, description: :not_given, deprecation_reason: nil, method: nil, hash_key: nil, dig: nil, resolver_method: nil, connection: nil, max_page_size: :not_given, default_page_size: :not_given, scope: nil, introspection: false, camelize: true, trace: nil, complexity: nil, ast_node: nil, extras: EMPTY_ARRAY, extensions: EMPTY_ARRAY, connection_extension: self.class.connection_extension, resolver_class: nil, subscription_scope: nil, relay_node_field: false, relay_nodes_field: false, method_conflict_warning: true, broadcastable: nil, arguments: EMPTY_HASH, directives: EMPTY_HASH, validates: EMPTY_ARRAY, fallback_value: :not_given, &definition_block) ⇒ Field

Returns a new instance of Field.

Parameters:

  • name (Symbol) (defaults to: nil)

    The underscore-cased version of this field name (will be camelized for the GraphQL API)

  • type (Class, GraphQL::BaseType, Array) (defaults to: nil)

    The return type of this field

  • owner (Class) (defaults to: nil)

    The type that this field belongs to

  • null (Boolean) (defaults to: nil)

    (defaults to true) true if this field may return null, false if it is never null

  • description (String) (defaults to: :not_given)

    Field description

  • deprecation_reason (String) (defaults to: nil)

    If present, the field is marked “deprecated” with this message

  • method (Symbol) (defaults to: nil)

    The method to call on the underlying object to resolve this field (defaults to name)

  • hash_key (String, Symbol) (defaults to: nil)

    The hash key to lookup on the underlying object (if its a Hash) to resolve this field (defaults to name or name.to_s)

  • dig (Array<String, Symbol>) (defaults to: nil)

    The nested hash keys to lookup on the underlying hash to resolve this field using dig

  • resolver_method (Symbol) (defaults to: nil)

    The method on the type to call to resolve this field (defaults to name)

  • connection (Boolean) (defaults to: nil)

    true if this field should get automagic connection behavior; default is to infer by *Connection in the return type name

  • connection_extension (Class) (defaults to: self.class.connection_extension)

    The extension to add, to implement connections. If nil, no extension is added.

  • max_page_size (Integer, nil) (defaults to: :not_given)

    For connections, the maximum number of items to return from this field, or nil to allow unlimited results.

  • default_page_size (Integer, nil) (defaults to: :not_given)

    For connections, the default number of items to return from this field, or nil to return unlimited results.

  • introspection (Boolean) (defaults to: false)

    If true, this field will be marked as #introspection? and the name may begin with __

  • resolver_class (Class) (defaults to: nil)

    (Private) A Resolver which this field was derived from. Use resolver: to create a field with a resolver.

  • arguments ({String=>GraphQL::Schema::Argument, Hash}) (defaults to: EMPTY_HASH)

    Arguments for this field (may be added in the block, also)

  • camelize (Boolean) (defaults to: true)

    If true, the field name will be camelized when building the schema

  • complexity (Numeric) (defaults to: nil)

    When provided, set the complexity for this field

  • scope (Boolean) (defaults to: nil)

    If true, the return type’s .scope_items method will be called on the return value

  • subscription_scope (Symbol, String) (defaults to: nil)

    A key in context which will be used to scope subscription payloads

  • extensions (Array<Class, Hash<Class => Object>>) (defaults to: EMPTY_ARRAY)

    Named extensions to apply to this field (see also #extension)

  • directives (Hash{Class => Hash}) (defaults to: EMPTY_HASH)

    Directives to apply to this field

  • trace (Boolean) (defaults to: nil)

    If true, a Tracing tracer will measure this scalar field

  • broadcastable (Boolean) (defaults to: nil)

    Whether or not this field can be distributed in subscription broadcasts

  • ast_node (Language::Nodes::FieldDefinition, nil) (defaults to: nil)

    If this schema was parsed from definition, this AST node defined the field

  • method_conflict_warning (Boolean) (defaults to: true)

    If false, skip the warning if this field’s method conflicts with a built-in method

  • validates (Array<Hash>) (defaults to: EMPTY_ARRAY)

    Configurations for validating this field



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# File 'lib/graphql/schema/field.rb', line 221

def initialize(type: nil, name: nil, owner: nil, null: nil, description: :not_given, deprecation_reason: nil, method: nil, hash_key: nil, dig: nil, resolver_method: nil, connection: nil, max_page_size: :not_given, default_page_size: :not_given, scope: nil, introspection: false, camelize: true, trace: nil, complexity: nil, ast_node: nil, extras: EMPTY_ARRAY, extensions: EMPTY_ARRAY, connection_extension: self.class.connection_extension, resolver_class: nil, subscription_scope: nil, relay_node_field: false, relay_nodes_field: false, method_conflict_warning: true, broadcastable: nil, arguments: EMPTY_HASH, directives: EMPTY_HASH, validates: EMPTY_ARRAY, fallback_value: :not_given, &definition_block)
  if name.nil?
    raise ArgumentError, "missing first `name` argument or keyword `name:`"
  end
  if !(resolver_class)
    if type.nil?
      raise ArgumentError, "missing second `type` argument or keyword `type:`"
    end
  end
  @original_name = name
  name_s = -name.to_s
  @underscored_name = -Member::BuildType.underscore(name_s)
  @name = -(camelize ? Member::BuildType.camelize(name_s) : name_s)
  if description != :not_given
    @description = description
  end
  self.deprecation_reason = deprecation_reason

  if method && hash_key && dig
    raise ArgumentError, "Provide `method:`, `hash_key:` _or_ `dig:`, not multiple. (called with: `method: #{method.inspect}, hash_key: #{hash_key.inspect}, dig: #{dig.inspect}`)"
  end

  if resolver_method
    if method
      raise ArgumentError, "Provide `method:` _or_ `resolver_method:`, not both. (called with: `method: #{method.inspect}, resolver_method: #{resolver_method.inspect}`)"
    end

    if hash_key || dig
      raise ArgumentError, "Provide `hash_key:`, `dig:`, _or_ `resolver_method:`, not multiple. (called with: `hash_key: #{hash_key.inspect}, dig: #{dig.inspect}, resolver_method: #{resolver_method.inspect}`)"
    end
  end

  method_name = method || hash_key || name_s
  @dig_keys = dig
  if hash_key
    @hash_key = hash_key
    @hash_key_str = hash_key.to_s
  end

  @method_str = -method_name.to_s
  @method_sym = method_name.to_sym
  @resolver_method = (resolver_method || name_s).to_sym
  @complexity = complexity
  @return_type_expr = type
  @return_type_null = if !null.nil?
    null
  elsif resolver_class
    nil
  else
    true
  end
  @connection = connection
  @has_max_page_size = max_page_size != :not_given
  @max_page_size = max_page_size == :not_given ? nil : max_page_size
  @has_default_page_size = default_page_size != :not_given
  @default_page_size = default_page_size == :not_given ? nil : default_page_size
  @introspection = introspection
  @extras = extras
  if !broadcastable.nil?
    @broadcastable = broadcastable
  end
  @resolver_class = resolver_class
  @scope = scope
  @trace = trace
  @relay_node_field = relay_node_field
  @relay_nodes_field = relay_nodes_field
  @ast_node = ast_node
  @method_conflict_warning = method_conflict_warning
  @fallback_value = fallback_value

  arguments.each do |name, arg|
    case arg
    when Hash
      argument(name: name, **arg)
    when GraphQL::Schema::Argument
      add_argument(arg)
    when Array
      arg.each { |a| add_argument(a) }
    else
      raise ArgumentError, "Unexpected argument config (#{arg.class}): #{arg.inspect}"
    end
  end

  @owner = owner
  @subscription_scope = subscription_scope

  @extensions = EMPTY_ARRAY
  @call_after_define = false
  # This should run before connection extension,
  # but should it run after the definition block?
  if scoped?
    self.extension(ScopeExtension)
  end

  # The problem with putting this after the definition_block
  # is that it would override arguments
  if connection? && connection_extension
    self.extension(connection_extension)
  end

  # Do this last so we have as much context as possible when initializing them:
  if extensions.any?
    self.extensions(extensions)
  end

  if resolver_class && resolver_class.extensions.any?
    self.extensions(resolver_class.extensions)
  end

  if directives.any?
    directives.each do |(dir_class, options)|
      self.directive(dir_class, **options)
    end
  end

  if !validates.empty?
    self.validates(validates)
  end

  if definition_block
    if definition_block.arity == 1
      yield self
    else
      instance_eval(&definition_block)
    end
  end

  self.extensions.each(&:after_define_apply)
  @call_after_define = true
end

Instance Attribute Details

#description(text = nil) ⇒ String

Parameters:

  • text (String) (defaults to: nil)

Returns:

  • (String)


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# File 'lib/graphql/schema/field.rb', line 367

def description(text = nil)
  if text
    @description = text
  elsif defined?(@description)
    @description
  elsif @resolver_class
    @description || @resolver_class.description
  else
    nil
  end
end

#dig_keysObject (readonly)

Returns the value of attribute dig_keys.



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# File 'lib/graphql/schema/field.rb', line 32

def dig_keys
  @dig_keys
end

#hash_keyObject (readonly)

Returns the value of attribute hash_key.



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# File 'lib/graphql/schema/field.rb', line 31

def hash_key
  @hash_key
end

#method_strString (readonly)

Returns Method or hash key on the underlying object to look up.

Returns:

  • (String)

    Method or hash key on the underlying object to look up



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# File 'lib/graphql/schema/field.rb', line 29

def method_str
  @method_str
end

#method_symSymbol (readonly)

Returns Method or hash key on the underlying object to look up.

Returns:

  • (Symbol)

    Method or hash key on the underlying object to look up



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# File 'lib/graphql/schema/field.rb', line 26

def method_sym
  @method_sym
end

#nameString (readonly) Also known as: graphql_name

Returns the GraphQL name for this field, camelized unless camelize: false is provided.

Returns:

  • (String)

    the GraphQL name for this field, camelized unless camelize: false is provided



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# File 'lib/graphql/schema/field.rb', line 20

def name
  @name
end

#original_nameSymbol (readonly)

Returns the original name of the field, passed in by the user.

Returns:

  • (Symbol)

    the original name of the field, passed in by the user



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# File 'lib/graphql/schema/field.rb', line 58

def original_name
  @original_name
end

#ownerClass

Returns The thing this field was defined on (type, mutation, resolver).

Returns:

  • (Class)

    The thing this field was defined on (type, mutation, resolver)



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# File 'lib/graphql/schema/field.rb', line 44

def owner
  @owner
end

#relay_node_fieldObject (readonly)

Returns Boolean.

Returns:

  • Boolean



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# File 'lib/graphql/schema/field.rb', line 183

def relay_node_field
  @relay_node_field
end

#relay_nodes_fieldObject (readonly)

Returns Boolean.

Returns:

  • Boolean



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# File 'lib/graphql/schema/field.rb', line 185

def relay_nodes_field
  @relay_nodes_field
end

#subscription_scopeString?

Returns:

  • (String, nil)


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# File 'lib/graphql/schema/field.rb', line 80

def subscription_scope
  @subscription_scope || (@resolver_class.respond_to?(:subscription_scope) ? @resolver_class.subscription_scope : nil)
end

#traceBoolean (readonly)

Returns Apply tracing to this field? (Default: skip scalars, this is the override value).

Returns:

  • (Boolean)

    Apply tracing to this field? (Default: skip scalars, this is the override value)



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# File 'lib/graphql/schema/field.rb', line 77

def trace
  @trace
end

#typeObject



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# File 'lib/graphql/schema/field.rb', line 566

def type
  if @resolver_class
    return_type = @return_type_expr || @resolver_class.type_expr
    if return_type.nil?
      raise MissingReturnTypeError, "Can't determine the return type for #{self.path} (it has `resolver: #{@resolver_class}`, perhaps that class is missing a `type ...` declaration, or perhaps its type causes a cyclical loading issue)"
    end
    nullable = @return_type_null.nil? ? @resolver_class.null : @return_type_null
    Member::BuildType.parse_type(return_type, null: nullable)
  else
    @type ||= Member::BuildType.parse_type(@return_type_expr, null: @return_type_null)
  end
rescue GraphQL::Schema::InvalidDocumentError, MissingReturnTypeError => err
  # Let this propagate up
  raise err
rescue StandardError => err
  raise MissingReturnTypeError, "Failed to build return type for #{@owner.graphql_name}.#{name} from #{@return_type_expr.inspect}: (#{err.class}) #{err.message}", err.backtrace
end

Class Method Details

.connection_extension(new_extension_class = nil) ⇒ Class

This extension is applied to fields when #connection? is true.

You can override it in your base field definition.

Examples:

Configuring a custom extension

class Types::BaseField < GraphQL::Schema::Field
  connection_extension(MyCustomExtension)
end

Returns:



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# File 'lib/graphql/schema/field.rb', line 174

def self.connection_extension(new_extension_class = nil)
  if new_extension_class
    @connection_extension = new_extension_class
  else
    @connection_extension ||= find_inherited_value(:connection_extension, ConnectionExtension)
  end
end

.from_options(name = nil, type = nil, desc = nil, resolver: nil, mutation: nil, subscription: nil, **kwargs, &block) ⇒ GraphQL::Schema:Field

Create a field instance from a list of arguments, keyword arguments, and a block.

This method implements prioritization between the resolver or mutation defaults and the local overrides via other keywords.

It also normalizes positional arguments into keywords for #initialize.

Parameters:

  • resolver (Class) (defaults to: nil)

    A Resolver class to use for field configuration

  • mutation (Class) (defaults to: nil)

    A Mutation class to use for field configuration

  • subscription (Class) (defaults to: nil)

    A Subscription class to use for field configuration

Returns:

  • (GraphQL::Schema:Field)

    an instance of `self

See Also:

  • for other options


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# File 'lib/graphql/schema/field.rb', line 96

def self.from_options(name = nil, type = nil, desc = nil, resolver: nil, mutation: nil, subscription: nil,**kwargs, &block)
  if (resolver_class = resolver || mutation || subscription)
    # Add a reference to that parent class
    kwargs[:resolver_class] = resolver_class
  end

  if name
    kwargs[:name] = name
  end

  if !type.nil?
    if desc
      if kwargs[:description]
        raise ArgumentError, "Provide description as a positional argument or `description:` keyword, but not both (#{desc.inspect}, #{kwargs[:description].inspect})"
      end

      kwargs[:description] = desc
      kwargs[:type] = type
    elsif (resolver || mutation) && type.is_a?(String)
      # The return type should be copied from the resolver, and the second positional argument is the description
      kwargs[:description] = type
    else
      kwargs[:type] = type
    end
    if type.is_a?(Class) && type < GraphQL::Schema::Mutation
      raise ArgumentError, "Use `field #{name.inspect}, mutation: Mutation, ...` to provide a mutation to this field instead"
    end
  end
  new(**kwargs, &block)
end

Instance Method Details

#accessible?(context) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/graphql/schema/field.rb', line 592

def accessible?(context)
  if @resolver_class
    @resolver_class.accessible?(context)
  else
    true
  end
end

#authorized?(object, args, context) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/graphql/schema/field.rb', line 600

def authorized?(object, args, context)
  if @resolver_class
    # The resolver _instance_ will check itself during `resolve()`
    @resolver_class.authorized?(object, context)
  else
    if (arg_values = context[:current_arguments])
      # ^^ that's provided by the interpreter at runtime, and includes info about whether the default value was used or not.
      using_arg_values = true
      arg_values = arg_values.argument_values
    else
      arg_values = args
      using_arg_values = false
    end
    # Faster than `.any?`
    arguments(context).each_value do |arg|
      arg_key = arg.keyword
      if arg_values.key?(arg_key)
        arg_value = arg_values[arg_key]
        if using_arg_values
          if arg_value.default_used?
            # pass -- no auth required for default used
            next
          else
            application_arg_value = arg_value.value
            if application_arg_value.is_a?(GraphQL::Execution::Interpreter::Arguments)
              application_arg_value.keyword_arguments
            end
          end
        else
          application_arg_value = arg_value
        end

        if !arg.authorized?(object, application_arg_value, context)
          return false
        end
      end
    end
    true
  end
end

#broadcastable?Boolean?

If true, subscription updates with this field can be shared between viewers

Returns:

  • (Boolean, nil)

See Also:



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# File 'lib/graphql/schema/field.rb', line 355

def broadcastable?
  if defined?(@broadcastable)
    @broadcastable
  elsif @resolver_class
    @resolver_class.broadcastable?
  else
    nil
  end
end

#calculate_complexity(query:, nodes:, child_complexity:) ⇒ Object



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# File 'lib/graphql/schema/field.rb', line 454

def calculate_complexity(query:, nodes:, child_complexity:)
  if respond_to?(:complexity_for)
    lookahead = GraphQL::Execution::Lookahead.new(query: query, field: self, ast_nodes: nodes, owner_type: owner)
    complexity_for(child_complexity: child_complexity, query: query, lookahead: lookahead)
  elsif connection?
    arguments = query.arguments_for(nodes.first, self)
    max_possible_page_size = nil
    if arguments.respond_to?(:[]) # It might have been an error
      if arguments[:first]
        max_possible_page_size = arguments[:first]
      end

      if arguments[:last] && (max_possible_page_size.nil? || arguments[:last] > max_possible_page_size)
        max_possible_page_size = arguments[:last]
      end
    end

    if max_possible_page_size.nil?
      max_possible_page_size = default_page_size || query.schema.default_page_size || max_page_size || query.schema.default_max_page_size
    end

    if max_possible_page_size.nil?
      raise GraphQL::Error, "Can't calculate complexity for #{path}, no `first:`, `last:`, `default_page_size`, `max_page_size` or `default_max_page_size`"
    else
       = 0
      lookahead = GraphQL::Execution::Lookahead.new(query: query, field: self, ast_nodes: nodes, owner_type: owner)

      if (page_info_lookahead = lookahead.selection(:page_info)).selected?
         += 1 # pageInfo
         += page_info_lookahead.selections.size # subfields
      end

      if lookahead.selects?(:total) || lookahead.selects?(:total_count) || lookahead.selects?(:count)
         += 1
      end

      nodes_edges_complexity = 0
      nodes_edges_complexity += 1 if lookahead.selects?(:edges)
      nodes_edges_complexity += 1 if lookahead.selects?(:nodes)

      # Possible bug: selections on `edges` and `nodes` are _both_ multiplied here. Should they be?
      items_complexity = child_complexity -  - nodes_edges_complexity
      # Add 1 for _this_ field
      1 + (max_possible_page_size * items_complexity) +  + nodes_edges_complexity
    end
  else
    defined_complexity = complexity
    case defined_complexity
    when Proc
      arguments = query.arguments_for(nodes.first, self)
      if arguments.is_a?(GraphQL::ExecutionError)
        return child_complexity
      elsif arguments.respond_to?(:keyword_arguments)
        arguments = arguments.keyword_arguments
      end

      defined_complexity.call(query.context, arguments, child_complexity)
    when Numeric
      defined_complexity + child_complexity
    else
      raise("Invalid complexity: #{defined_complexity.inspect} on #{path} (#{inspect})")
    end
  end
end

#complexity(new_complexity = nil) ⇒ Object



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# File 'lib/graphql/schema/field.rb', line 519

def complexity(new_complexity = nil)
  case new_complexity
  when Proc
    if new_complexity.parameters.size != 3
      fail(
        "A complexity proc should always accept 3 parameters: ctx, args, child_complexity. "\
        "E.g.: complexity ->(ctx, args, child_complexity) { child_complexity * args[:limit] }"
      )
    else
      @complexity = new_complexity
    end
  when Numeric
    @complexity = new_complexity
  when nil
    if @resolver_class
      @complexity || @resolver_class.complexity || 1
    else
      @complexity || 1
    end
  else
    raise("Invalid complexity: #{new_complexity.inspect} on #{@name}")
  end
end

#connection?Boolean

Can be set with connection: true|false or inferred from a type name ending in *Connection

Returns:

  • (Boolean)

    if true, this field will be wrapped with Relay connection behavior



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# File 'lib/graphql/schema/field.rb', line 129

def connection?
  if @connection.nil?
    # Provide default based on type name
    return_type_name = if @return_type_expr
      Member::BuildType.to_type_name(@return_type_expr)
    elsif @resolver_class && @resolver_class.type
      Member::BuildType.to_type_name(@resolver_class.type)
    else
      # As a last ditch, try to force loading the return type:
      type.unwrap.name
    end
    @connection = return_type_name.end_with?("Connection")
  else
    @connection
  end
end

#default_page_sizeInteger?

Returns Applied to connections if #has_default_page_size?.

Returns:



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# File 'lib/graphql/schema/field.rb', line 559

def default_page_size
  @default_page_size || (@resolver_class && @resolver_class.default_page_size)
end

#extension(extension_class, options = nil) ⇒ void

This method returns an undefined value.

Add extension to this field, initialized with options if provided.

Examples:

adding an extension

extension(MyExtensionClass)

adding an extension with options

extension(MyExtensionClass, filter: true)

Parameters:

  • extension_class (Class)
  • options (Hash) (defaults to: nil)

    if provided, given as options: when initializing extension.



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# File 'lib/graphql/schema/field.rb', line 419

def extension(extension_class, options = nil)
  extension_inst = extension_class.new(field: self, options: options)
  if @extensions.frozen?
    @extensions = @extensions.dup
  end
  if @call_after_define
    extension_inst.after_define_apply
  end
  @extensions << extension_inst
  nil
end

#extensions(new_extensions = nil) ⇒ Array<GraphQL::Schema::FieldExtension>

Read extension instances from this field, or add new classes/options to be initialized on this field. Extensions are executed in the order they are added.

Examples:

adding an extension

extensions([MyExtensionClass])

adding multiple extensions

extensions([MyExtensionClass, AnotherExtensionClass])

adding an extension with options

extensions([MyExtensionClass, { AnotherExtensionClass => { filter: true } }])

Parameters:

  • extensions (Array<Class, Hash<Class => Hash>>)

    Add extensions to this field. For hash elements, only the first key/value is used.

Returns:



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# File 'lib/graphql/schema/field.rb', line 394

def extensions(new_extensions = nil)
  if new_extensions
    new_extensions.each do |extension_config|
      if extension_config.is_a?(Hash)
        extension_class, options = *extension_config.to_a[0]
        self.extension(extension_class, options)
      else
        self.extension(extension_config)
      end
    end
  end
  @extensions
end

#extras(new_extras = nil) ⇒ Array<Symbol>

Read extras (as symbols) from this field, or add new extras to be opted into by this field’s resolver.

Parameters:

  • new_extras (Array<Symbol>) (defaults to: nil)

    Add extras to this field

Returns:

  • (Array<Symbol>)


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# File 'lib/graphql/schema/field.rb', line 436

def extras(new_extras = nil)
  if new_extras.nil?
    # Read the value
    field_extras = @extras
    if @resolver_class && @resolver_class.extras.any?
      field_extras + @resolver_class.extras
    else
      field_extras
    end
  else
    if @extras.frozen?
      @extras = @extras.dup
    end
    # Append to the set of extras on this field
    @extras.concat(new_extras)
  end
end

#fetch_extra(extra_name, ctx) ⇒ Object

Parameters:



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# File 'lib/graphql/schema/field.rb', line 750

def fetch_extra(extra_name, ctx)
  if extra_name != :path && extra_name != :ast_node && respond_to?(extra_name)
    self.public_send(extra_name)
  elsif ctx.respond_to?(extra_name)
    ctx.public_send(extra_name)
  else
    raise GraphQL::RequiredImplementationMissingError, "Unknown field extra for #{self.path}: #{extra_name.inspect}"
  end
end

#has_default_page_size?Boolean

Returns True if this field’s #default_page_size should override the schema default.

Returns:

  • (Boolean)

    True if this field’s #default_page_size should override the schema default.



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# File 'lib/graphql/schema/field.rb', line 554

def has_default_page_size?
  @has_default_page_size || (@resolver_class && @resolver_class.has_default_page_size?)
end

#has_max_page_size?Boolean

Returns True if this field’s #max_page_size should override the schema default.

Returns:

  • (Boolean)

    True if this field’s #max_page_size should override the schema default.



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# File 'lib/graphql/schema/field.rb', line 544

def has_max_page_size?
  @has_max_page_size || (@resolver_class && @resolver_class.has_max_page_size?)
end

#inspectObject



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# File 'lib/graphql/schema/field.rb', line 70

def inspect
  "#<#{self.class} #{path}#{all_argument_definitions.any? ? "(...)" : ""}: #{type.to_type_signature}>"
end

#introspection?Boolean

Returns Is this field a predefined introspection field?.

Returns:

  • (Boolean)

    Is this field a predefined introspection field?



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# File 'lib/graphql/schema/field.rb', line 66

def introspection?
  @introspection
end

#max_page_sizeInteger?

Returns Applied to connections if #has_max_page_size?.

Returns:



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# File 'lib/graphql/schema/field.rb', line 549

def max_page_size
  @max_page_size || (@resolver_class && @resolver_class.max_page_size)
end

#method_conflict_warning?Boolean

Returns Should we warn if this field’s name conflicts with a built-in method?.

Returns:

  • (Boolean)

    Should we warn if this field’s name conflicts with a built-in method?



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# File 'lib/graphql/schema/field.rb', line 188

def method_conflict_warning?
  @method_conflict_warning
end

#owner_typeClass

Returns The GraphQL type this field belongs to. (For fields defined on mutations, it’s the payload type).

Returns:

  • (Class)

    The GraphQL type this field belongs to. (For fields defined on mutations, it’s the payload type)



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# File 'lib/graphql/schema/field.rb', line 47

def owner_type
  @owner_type ||= if owner.nil?
    raise GraphQL::InvariantError, "Field #{original_name.inspect} (graphql name: #{graphql_name.inspect}) has no owner, but all fields should have an owner. How did this happen?!"
  elsif owner < GraphQL::Schema::Mutation
    owner.payload_type
  else
    owner
  end
end

#resolve(object, args, query_ctx) ⇒ Object

This method is called by the interpreter for each field. You can extend it in your base field classes.

Parameters:



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# File 'lib/graphql/schema/field.rb', line 646

def resolve(object, args, query_ctx)
  # Unwrap the GraphQL object to get the application object.
  application_object = object.object
  method_receiver = nil
  method_to_call = nil
  method_args = nil

  Schema::Validator.validate!(validators, application_object, query_ctx, args)

  query_ctx.schema.after_lazy(self.authorized?(application_object, args, query_ctx)) do |is_authorized|
    if is_authorized
      with_extensions(object, args, query_ctx) do |obj, ruby_kwargs|
        method_args = ruby_kwargs
        if @resolver_class
          if obj.is_a?(GraphQL::Schema::Object)
            obj = obj.object
          end
          obj = @resolver_class.new(object: obj, context: query_ctx, field: self)
        end

        inner_object = obj.object

        if defined?(@hash_key)
          hash_value = if inner_object.is_a?(Hash)
            inner_object.key?(@hash_key) ? inner_object[@hash_key] : inner_object[@hash_key_str]
          elsif inner_object.respond_to?(:[])
            inner_object[@hash_key]
          else
            nil
          end
          if hash_value == false
            hash_value
          else
            hash_value || (@fallback_value != :not_given ? @fallback_value : nil)
          end
        elsif obj.respond_to?(resolver_method)
          method_to_call = resolver_method
          method_receiver = obj
          # Call the method with kwargs, if there are any
          if ruby_kwargs.any?
            obj.public_send(resolver_method, **ruby_kwargs)
          else
            obj.public_send(resolver_method)
          end
        elsif inner_object.is_a?(Hash)
          if @dig_keys
            inner_object.dig(*@dig_keys)
          elsif inner_object.key?(@method_sym)
            inner_object[@method_sym]
          elsif inner_object.key?(@method_str)
            inner_object[@method_str]
          elsif @fallback_value != :not_given
            @fallback_value
          else
            nil
          end
        elsif inner_object.respond_to?(@method_sym)
          method_to_call = @method_sym
          method_receiver = obj.object
          if ruby_kwargs.any?
            inner_object.public_send(@method_sym, **ruby_kwargs)
          else
            inner_object.public_send(@method_sym)
          end
        elsif @fallback_value != :not_given
          @fallback_value
        else
          raise <<-ERR
        Failed to implement #{@owner.graphql_name}.#{@name}, tried:

        - `#{obj.class}##{resolver_method}`, which did not exist
        - `#{inner_object.class}##{@method_sym}`, which did not exist
        - Looking up hash key `#{@method_sym.inspect}` or `#{@method_str.inspect}` on `#{inner_object}`, but it wasn't a Hash

        To implement this field, define one of the methods above (and check for typos), or supply a `fallback_value`.
        ERR
        end
      end
    else
      raise GraphQL::UnauthorizedFieldError.new(object: application_object, type: object.class, context: query_ctx, field: self)
    end
  end
rescue GraphQL::UnauthorizedFieldError => err
  err.field ||= self
  begin
    query_ctx.schema.unauthorized_field(err)
  rescue GraphQL::ExecutionError => err
    err
  end
rescue GraphQL::UnauthorizedError => err
  begin
    query_ctx.schema.unauthorized_object(err)
  rescue GraphQL::ExecutionError => err
    err
  end
rescue ArgumentError
  if method_receiver && method_to_call
    assert_satisfactory_implementation(method_receiver, method_to_call, method_args)
  end
  # if the line above doesn't raise, re-raise
  raise
end

#resolverClass? Also known as: mutation

Returns The Resolver this field was derived from, if there is one.

Returns:

  • (Class, nil)

    The Resolver this field was derived from, if there is one



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# File 'lib/graphql/schema/field.rb', line 61

def resolver
  @resolver_class
end

#resolver_methodSymbol

Returns The method on the type to look up.

Returns:

  • (Symbol)

    The method on the type to look up



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# File 'lib/graphql/schema/field.rb', line 35

def resolver_method
  if @resolver_class
    @resolver_class.resolver_method
  else
    @resolver_method
  end
end

#scoped?Boolean

Returns if true, the return type’s .scope_items method will be applied to this field’s return value.

Returns:

  • (Boolean)

    if true, the return type’s .scope_items method will be applied to this field’s return value



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# File 'lib/graphql/schema/field.rb', line 147

def scoped?
  if !@scope.nil?
    # The default was overridden
    @scope
  elsif @return_type_expr
    # Detect a list return type, but don't call `type` since that may eager-load an otherwise lazy-loaded type
    @return_type_expr.is_a?(Array) ||
      (@return_type_expr.is_a?(String) && @return_type_expr.include?("[")) ||
      connection?
  elsif @resolver_class
    resolver_type = @resolver_class.type_expr
    resolver_type.is_a?(Array) ||
      (resolver_type.is_a?(String) && resolver_type.include?("[")) ||
      connection?
  else
    false
  end
end

#visible?(context) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/graphql/schema/field.rb', line 584

def visible?(context)
  if @resolver_class
    @resolver_class.visible?(context)
  else
    true
  end
end