Class: GraphQL::Schema::Resolver
- Inherits:
-
Object
- Object
- GraphQL::Schema::Resolver
- Extended by:
- Member::BaseDSLMethods, Member::HasArguments
- Includes:
- Member::GraphQLTypeNames
- Defined in:
- lib/graphql/schema/resolver.rb
Overview
A class-based container for field configuration and resolution logic. It supports:
- Arguments, via
.argument(...)
helper, which will be applied to the field. - Return type, via
.type(..., null: ...)
, which will be applied to the field. - Description, via
.description(...)
, which will be applied to the field - Resolution, via
#resolve(**args)
method, which will be called to resolve the field. #object
and#context
accessors for use during#resolve
.
Resolvers can be attached with the resolver:
option in a field(...)
call.
A resolver’s configuration may be overridden with other keywords in the field(...)
call.
See the Resolver.field_options to see how a Resolver becomes a set of field configuration options.
Direct Known Subclasses
Defined Under Namespace
Classes: LoadApplicationObjectFailedError
Constant Summary
Constants included from Member::GraphQLTypeNames
Member::GraphQLTypeNames::Boolean, Member::GraphQLTypeNames::ID, Member::GraphQLTypeNames::Int
Instance Attribute Summary collapse
-
#context ⇒ GraphQL::Query::Context
readonly
-
#object ⇒ Object
readonly
The application object this field is being resolved on.
Class Method Summary collapse
-
.argument(name, type, *rest, loads: nil, **kwargs, &block) ⇒ Object
Add an argument to this field’s signature, but also add some preparation hook methods which will be used for this argument.
-
.arguments_loads_as_type ⇒ Object
private
-
.complexity(new_complexity = nil) ⇒ Integer, Proc
Specifies the complexity of the field.
-
.extras(new_extras = nil) ⇒ Object
Additional info injected into #resolve.
-
.field_options ⇒ Object
-
.null(allow_null = nil) ⇒ Object
Specifies whether or not the field is nullable.
-
.resolve_method(new_method = nil) ⇒ Symbol
Default
:resolve
set below. -
.type(new_type = nil, null: nil) ⇒ Class
Call this method to get the return type of the field, or use it as a configuration method to assign a return type instead of generating one.
-
.type_expr ⇒ Object
A non-normalized type configuration, without
null
applied.
Instance Method Summary collapse
-
#authorized?(**args) ⇒ Boolean, early_return_data
Called after arguments are loaded, but before resolving.
-
#initialize(object:, context:) ⇒ Resolver
constructor
A new instance of Resolver.
-
#ready?(**args) ⇒ Boolean, early_return_data
Called before arguments are prepared.
-
#resolve(**args) ⇒ Object
Do the work.
-
#resolve_with_support(**args) ⇒ Object
private
This method is actually called by the runtime, it does some preparation and then eventually calls the user-defined
#resolve
method.
Methods included from Member::HasArguments
add_argument, argument, argument_class, arguments, own_arguments
Methods included from Member::BaseDSLMethods
accessible?, default_graphql_name, description, graphql_name, introspection, mutation, name, overridden_graphql_name, to_graphql, visible?
Constructor Details
#initialize(object:, context:) ⇒ Resolver
Returns a new instance of Resolver
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# File 'lib/graphql/schema/resolver.rb', line 29 def initialize(object:, context:) @object = object @context = context # Since this hash is constantly rebuilt, cache it for this call @arguments_by_keyword = {} self.class.arguments.each do |name, arg| @arguments_by_keyword[arg.keyword] = arg end @arguments_loads_as_type = self.class.arguments_loads_as_type end |
Instance Attribute Details
#context ⇒ GraphQL::Query::Context (readonly)
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# File 'lib/graphql/schema/resolver.rb', line 44 def context @context end |
#object ⇒ Object (readonly)
Returns The application object this field is being resolved on
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# File 'lib/graphql/schema/resolver.rb', line 41 def object @object end |
Class Method Details
.argument(name, type, *rest, loads: nil, **kwargs, &block) ⇒ Object
Add an argument to this field’s signature, but also add some preparation hook methods which will be used for this argument
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# File 'lib/graphql/schema/resolver.rb', line 324 def argument(name, type, *rest, loads: nil, **kwargs, &block) if loads arg_keyword = name.to_s.sub(/_id$/, "").to_sym kwargs[:as] = arg_keyword own_arguments_loads_as_type[arg_keyword] = loads end arg_defn = super(name, type, *rest, **kwargs, &block) if loads class_eval <<-RUBY, __FILE__, __LINE__ + 1 def load_#{arg_defn.keyword}(value) load_application_object(:#{arg_defn.keyword}, value) end RUBY else class_eval <<-RUBY, __FILE__, __LINE__ + 1 def load_#{arg_defn.keyword}(value) value end RUBY end arg_defn end |
.arguments_loads_as_type ⇒ Object
This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.
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# File 'lib/graphql/schema/resolver.rb', line 350 def arguments_loads_as_type inherited_lookups = superclass.respond_to?(:arguments_loads_as_type) ? superclass.arguments_loads_as_type : {} inherited_lookups.merge(own_arguments_loads_as_type) end |
.complexity(new_complexity = nil) ⇒ Integer, Proc
Specifies the complexity of the field. Defaults to 1
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# File 'lib/graphql/schema/resolver.rb', line 296 def complexity(new_complexity = nil) if new_complexity @complexity = new_complexity end @complexity || (superclass.respond_to?(:complexity) ? superclass.complexity : 1) end |
.extras(new_extras = nil) ⇒ Object
Additional info injected into #resolve
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# File 'lib/graphql/schema/resolver.rb', line 250 def extras(new_extras = nil) if new_extras @own_extras = new_extras end own_extras = @own_extras || [] own_extras + (superclass.respond_to?(:extras) ? superclass.extras : []) end |
.field_options ⇒ Object
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# File 'lib/graphql/schema/resolver.rb', line 303 def { type: type_expr, description: description, extras: extras, method: :resolve_with_support, resolver_class: self, arguments: arguments, null: null, complexity: complexity, } end |
.null(allow_null = nil) ⇒ Object
Specifies whether or not the field is nullable. Defaults to true
TODO unify with #type
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# File 'lib/graphql/schema/resolver.rb', line 261 def null(allow_null = nil) if !allow_null.nil? @null = allow_null end @null.nil? ? (superclass.respond_to?(:null) ? superclass.null : true) : @null end |
.resolve_method(new_method = nil) ⇒ Symbol
Default :resolve
set below.
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# File 'lib/graphql/schema/resolver.rb', line 241 def resolve_method(new_method = nil) if new_method @resolve_method = new_method end @resolve_method || (superclass.respond_to?(:resolve_method) ? superclass.resolve_method : :resolve) end |
.type(new_type = nil, null: nil) ⇒ Class
Call this method to get the return type of the field, or use it as a configuration method to assign a return type instead of generating one. TODO unify with #null
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# File 'lib/graphql/schema/resolver.rb', line 276 def type(new_type = nil, null: nil) if new_type if null.nil? raise ArgumentError, "required argument `null:` is missing" end @type_expr = new_type @null = null else if @type_expr GraphQL::Schema::Member::BuildType.parse_type(@type_expr, null: @null) elsif superclass.respond_to?(:type) superclass.type else nil end end end |
.type_expr ⇒ Object
A non-normalized type configuration, without null
applied
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# File 'lib/graphql/schema/resolver.rb', line 317 def type_expr @type_expr || (superclass.respond_to?(:type_expr) ? superclass.type_expr : nil) end |
Instance Method Details
#authorized?(**args) ⇒ Boolean, early_return_data
Called after arguments are loaded, but before resolving.
Override it to check everything before calling the mutation.
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# File 'lib/graphql/schema/resolver.rb', line 128 def (**args) true end |
#ready?(**args) ⇒ Boolean, early_return_data
Called before arguments are prepared. Implement this hook to make checks before doing any work.
If it returns a lazy object (like a promise), it will be synced by GraphQL (but the resulting value won’t be used).
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# File 'lib/graphql/schema/resolver.rb', line 117 def ready?(**args) true end |
#resolve(**args) ⇒ Object
Do the work. Everything happens here.
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# File 'lib/graphql/schema/resolver.rb', line 103 def resolve(**args) raise NotImplementedError, "#{self.class.name}#resolve should execute the field's logic" end |
#resolve_with_support(**args) ⇒ Object
This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.
This method is actually called by the runtime,
it does some preparation and then eventually calls
the user-defined #resolve
method.
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# File 'lib/graphql/schema/resolver.rb', line 50 def resolve_with_support(**args) # First call the ready? hook which may raise ready_val = if args.any? ready?(**args) else ready? end context.schema.after_lazy(ready_val) do |is_ready, ready_early_return| if ready_early_return if is_ready != false raise "Unexpected result from #ready? (expected `true`, `false` or `[false, {...}]`): [#{.inspect}, #{ready_early_return.inspect}]" else ready_early_return end elsif is_ready # Then call each prepare hook, which may return a different value # for that argument, or may return a lazy object load_arguments_val = load_arguments(args) context.schema.after_lazy(load_arguments_val) do |loaded_args| # Then call `authorized?`, which may raise or may return a lazy object = if loaded_args.any? (loaded_args) else end (loaded_args) context.schema.after_lazy() do |(, early_return)| # If the `authorized?` returned two values, `false, early_return`, # then use the early return value instead of continuing if early_return if == false early_return else raise "Unexpected result from #authorized? (expected `true`, `false` or `[false, {...}]`): [#{.inspect}, #{early_return.inspect}]" end elsif # Finally, all the hooks have passed, so resolve it if loaded_args.any? public_send(self.class.resolve_method, **loaded_args) else public_send(self.class.resolve_method) end else nil end end end end end end |