Class: GraphQL::Schema::Resolver
- Inherits:
-
Object
- Object
- GraphQL::Schema::Resolver
- Extended by:
- Member::BaseDSLMethods, Member::HasArguments, Member::HasPath
- 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::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(*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.
-
.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?(**inputs) ⇒ 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::HasPath
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, introspection?, mutation, name, overridden_graphql_name, to_graphql, visible?
Constructor Details
#initialize(object:, context:) ⇒ Resolver
Returns a new instance of Resolver
32 33 34 35 36 37 38 39 40 41 |
# File 'lib/graphql/schema/resolver.rb', line 32 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)
47 48 49 |
# File 'lib/graphql/schema/resolver.rb', line 47 def context @context end |
#object ⇒ Object (readonly)
Returns The application object this field is being resolved on
44 45 46 |
# File 'lib/graphql/schema/resolver.rb', line 44 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
281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 |
# File 'lib/graphql/schema/resolver.rb', line 281 def argument(*args, **kwargs, &block) loads = kwargs[:loads] # Use `from_resolver: true` to short-circuit the InputObject's own `loads:` implementation # so that we can support `#load_{x}` methods below. arg_defn = super(*args, from_resolver: true, **kwargs) own_arguments_loads_as_type[arg_defn.keyword] = loads if loads if loads && arg_defn.type.list? class_eval <<-RUBY, __FILE__, __LINE__ + 1 def load_#{arg_defn.keyword}(values) argument = @arguments_by_keyword[:#{arg_defn.keyword}] lookup_as_type = @arguments_loads_as_type[:#{arg_defn.keyword}] context.schema.after_lazy(values) do |values2| GraphQL::Execution::Lazy.all(values2.map { |value| load_application_object(argument, lookup_as_type, value) }) end end RUBY elsif loads class_eval <<-RUBY, __FILE__, __LINE__ + 1 def load_#{arg_defn.keyword}(value) argument = @arguments_by_keyword[:#{arg_defn.keyword}] lookup_as_type = @arguments_loads_as_type[:#{arg_defn.keyword}] load_application_object(argument, lookup_as_type, 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.
318 319 320 321 |
# File 'lib/graphql/schema/resolver.rb', line 318 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
253 254 255 256 257 258 |
# File 'lib/graphql/schema/resolver.rb', line 253 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
207 208 209 210 211 212 213 |
# File 'lib/graphql/schema/resolver.rb', line 207 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
260 261 262 263 264 265 266 267 268 269 270 271 |
# File 'lib/graphql/schema/resolver.rb', line 260 def { type: type_expr, description: description, extras: extras, resolver_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
218 219 220 221 222 223 224 |
# File 'lib/graphql/schema/resolver.rb', line 218 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.
198 199 200 201 202 203 |
# File 'lib/graphql/schema/resolver.rb', line 198 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
233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 |
# File 'lib/graphql/schema/resolver.rb', line 233 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
274 275 276 |
# File 'lib/graphql/schema/resolver.rb', line 274 def type_expr @type_expr || (superclass.respond_to?(:type_expr) ? superclass.type_expr : nil) end |
Instance Method Details
#authorized?(**inputs) ⇒ Boolean, early_return_data
Called after arguments are loaded, but before resolving.
Override it to check everything before calling the mutation.
130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 |
# File 'lib/graphql/schema/resolver.rb', line 130 def (**inputs) self.class.arguments.each_value do |argument| arg_keyword = argument.keyword if inputs.key?(arg_keyword) && !(value = inputs[arg_keyword]).nil? && (value != argument.default_value) loads_type = @arguments_loads_as_type[arg_keyword] # If this argument resulted in an object being loaded, # then authorize this loaded object with its own policy. # # But if this argument was "just" a plain argument, like # a boolean, then authorize it based on the mutation. = if loads_type value else self end arg_auth, err = argument.(, context) if !arg_auth return arg_auth, err else true end else true end end 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).
119 120 121 |
# File 'lib/graphql/schema/resolver.rb', line 119 def ready?(**args) true end |
#resolve(**args) ⇒ Object
Do the work. Everything happens here.
105 106 107 |
# File 'lib/graphql/schema/resolver.rb', line 105 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.
53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 |
# File 'lib/graphql/schema/resolver.rb', line 53 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 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 |