Class: GraphQL::Schema::Resolver
- Inherits:
-
Object
- Object
- GraphQL::Schema::Resolver
- Includes:
- Member::GraphQLTypeNames, Member::HasPath
- Defined in:
- lib/graphql/schema/resolver.rb,
lib/graphql/schema/resolver/has_payload_type.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
Modules: HasPayloadType
Constant Summary
Constants included from Member::HasArguments
Member::HasArguments::NO_ARGUMENTS
Constants included from FindInheritedValue::EmptyObjects
FindInheritedValue::EmptyObjects::EMPTY_ARRAY, FindInheritedValue::EmptyObjects::EMPTY_HASH
Constants included from Member::GraphQLTypeNames
Member::GraphQLTypeNames::Boolean, Member::GraphQLTypeNames::ID, Member::GraphQLTypeNames::Int
Instance Attribute Summary collapse
-
#context ⇒ GraphQL::Query::Context
readonly
-
#field ⇒ GraphQL::Schema::Field
readonly
-
#object ⇒ Object
readonly
The application object this field is being resolved on.
Class Method Summary collapse
-
.argument(*args, **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.
-
.broadcastable(new_broadcastable) ⇒ Object
-
.broadcastable? ⇒ Boolean?
-
.complexity(new_complexity = nil) ⇒ Integer, Proc
Specifies the complexity of the field.
-
.extension(extension, **options) ⇒ Object
Registers new extension.
-
.extensions ⇒ Object
private
-
.extras(new_extras = nil) ⇒ Object
Additional info injected into #resolve.
-
.field_options ⇒ Object
-
.has_max_page_size? ⇒ Boolean
true
if this resolver or a superclass has an assignedmax_page_size
. -
.max_page_size(new_max_page_size = :not_given) ⇒ Integer?
Get or set the
max_page_size:
which will be configured for fields using this resolver (nil
means “unlimited max page size”.). -
.null(allow_null = nil) ⇒ Object
If
true
(default), then the return type for this resolver will be 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
-
#arguments ⇒ Object
-
#authorized?(**inputs) ⇒ Boolean, early_return_data
Called after arguments are loaded, but before resolving.
-
#dataloader ⇒ GraphQL::Dataloader
-
#initialize(object:, context:, field:) ⇒ 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. -
#unauthorized_object(err) ⇒ Object
Called when an object loaded by
loads:
fails the.authorized?
check for its resolved GraphQL object type.
Methods included from Member::BaseDSLMethods
accessible?, default_graphql_name, description, graphql_name, introspection, introspection?, mutation, name, overridden_graphql_name, visible?
Methods included from Member::HasArguments
add_argument, all_argument_definitions, argument, argument_class, arguments_statically_coercible?, coerce_arguments, own_arguments, validate_directive_argument
Methods included from Member::HasValidators
Methods included from Member::HasPath
Constructor Details
#initialize(object:, context:, field:) ⇒ Resolver
Returns a new instance of Resolver.
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# File 'lib/graphql/schema/resolver.rb', line 34 def initialize(object:, context:, field:) @object = object @context = context @field = field # Since this hash is constantly rebuilt, cache it for this call @arguments_by_keyword = {} self.class.arguments(context).each do |name, arg| @arguments_by_keyword[arg.keyword] = arg end @prepared_arguments = nil end |
Instance Attribute Details
#context ⇒ GraphQL::Query::Context (readonly)
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# File 'lib/graphql/schema/resolver.rb', line 50 def context @context end |
#field ⇒ GraphQL::Schema::Field (readonly)
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# File 'lib/graphql/schema/resolver.rb', line 58 def field @field 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 47 def object @object end |
Class Method Details
.argument(*args, **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 361 def argument(*args, **kwargs, &block) # Use `from_resolver: true` to short-circuit the InputObject's own `loads:` implementation # so that we can support `#load_{x}` methods below. super(*args, from_resolver: true, **kwargs) end |
.broadcastable(new_broadcastable) ⇒ Object
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# File 'lib/graphql/schema/resolver.rb', line 279 def broadcastable(new_broadcastable) @broadcastable = new_broadcastable end |
.broadcastable? ⇒ Boolean?
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# File 'lib/graphql/schema/resolver.rb', line 284 def broadcastable? if defined?(@broadcastable) @broadcastable else (superclass.respond_to?(:broadcastable?) ? superclass.broadcastable? : nil) end 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 272 def complexity(new_complexity = nil) if new_complexity @complexity = new_complexity end @complexity || (superclass.respond_to?(:complexity) ? superclass.complexity : 1) end |
.extension(extension, **options) ⇒ Object
Registers new extension
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# File 'lib/graphql/schema/resolver.rb', line 370 def extension(extension, **) @own_extensions ||= [] @own_extensions << {extension => } end |
.extensions ⇒ 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 376 def extensions own_exts = @own_extensions # Jump through some hoops to avoid creating arrays when we don't actually need them if superclass.respond_to?(:extensions) s_exts = superclass.extensions if own_exts if s_exts.any? own_exts + s_exts else own_exts end else s_exts end else own_exts || EMPTY_ARRAY end end |
.extras(new_extras = nil) ⇒ Object
Additional info injected into #resolve
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# File 'lib/graphql/schema/resolver.rb', line 224 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 313 def all_args = {} all_argument_definitions.each do |arg| if (prev_entry = all_args[arg.graphql_name]) if prev_entry.is_a?(Array) prev_entry << arg else all_args[arg.graphql_name] = [prev_entry, arg] end else all_args[arg.graphql_name] = arg end end field_opts = { type: type_expr, description: description, extras: extras, resolver_method: :resolve_with_support, resolver_class: self, arguments: all_args, null: null, complexity: complexity, broadcastable: broadcastable?, } # If there aren't any, then the returned array is `[].freeze`, # but passing that along breaks some user code. if (exts = extensions).any? field_opts[:extensions] = exts end if has_max_page_size? field_opts[:max_page_size] = max_page_size end field_opts end |
.has_max_page_size? ⇒ Boolean
Returns true
if this resolver or a superclass has an assigned max_page_size
.
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# File 'lib/graphql/schema/resolver.rb', line 309 def has_max_page_size? defined?(@max_page_size) || (superclass.respond_to?(:has_max_page_size?) && superclass.has_max_page_size?) end |
.max_page_size(new_max_page_size = :not_given) ⇒ Integer?
Get or set the max_page_size:
which will be configured for fields using this resolver
(nil
means “unlimited max page size”.)
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# File 'lib/graphql/schema/resolver.rb', line 296 def max_page_size(new_max_page_size = :not_given) if new_max_page_size != :not_given @max_page_size = new_max_page_size elsif defined?(@max_page_size) @max_page_size elsif superclass.respond_to?(:max_page_size) superclass.max_page_size else nil end end |
.null(allow_null = nil) ⇒ Object
If true
(default), then the return type for this resolver will be nullable.
If false
, then the return type is non-null.
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# File 'lib/graphql/schema/resolver.rb', line 237 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 215 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 252 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 354 def type_expr @type_expr || (superclass.respond_to?(:type_expr) ? superclass.type_expr : nil) end |
Instance Method Details
#arguments ⇒ Object
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# File 'lib/graphql/schema/resolver.rb', line 60 def arguments @prepared_arguments || raise("Arguments have not been prepared yet, still waiting for #load_arguments to resolve. (Call `.arguments` later in the code.)") end |
#authorized?(**inputs) ⇒ 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 147 def (**inputs) arg_owner = @field # || self.class args = arg_owner.arguments(context) (args, inputs) end |
#dataloader ⇒ GraphQL::Dataloader
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# File 'lib/graphql/schema/resolver.rb', line 53 def dataloader context.dataloader 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 136 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 122 def resolve(**args) raise GraphQL::RequiredImplementationMissingError, "#{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 68 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| @prepared_arguments = loaded_args Schema::Validator.validate!(self.class.validators, object, context, loaded_args, as: @field) # Then call `authorized?`, which may raise or may return a lazy object = if loaded_args.any? (**loaded_args) else end 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 raise GraphQL::UnauthorizedFieldError.new(context: context, object: object, type: field.owner, field: field) end end end end end end |
#unauthorized_object(err) ⇒ Object
Called when an object loaded by loads:
fails the .authorized?
check for its resolved GraphQL object type.
By default, the error is re-raised and passed along to GraphQL::Schema::Resolver.{Schema{Schema.unauthorized_object}.
Any value returned here will be used instead of of the loaded object.
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# File 'lib/graphql/schema/resolver.rb', line 159 def (err) raise err end |