[−][src]Derive Macro async_graphql::Interface
#[derive(Interface)] { // Attributes available to this derive: #[graphql] }
Define a GraphQL interface
Macro parameters
Attribute | description | Type | Optional |
---|---|---|---|
name | Object name | string | Y |
rename_fields | Rename all the fields according to the given case convention. The possible values are "lowercase", "UPPERCASE", "PascalCase", "camelCase", "snake_case", "SCREAMING_SNAKE_CASE". | string | Y |
rename_args | Rename all the arguments according to the given case convention. The possible values are "lowercase", "UPPERCASE", "PascalCase", "camelCase", "snake_case", "SCREAMING_SNAKE_CASE". | string | Y |
field | Fields of this Interface | [InterfaceField] | N |
extends | Add fields to an entity that's defined in another service | bool | Y |
visible | If false , it will not be displayed in introspection. See also the Book. | bool | Y |
visible | Call the specified function. If the return value is false , it will not be displayed in introspection. | string | Y |
Field parameters
Attribute | description | Type | Optional |
---|---|---|---|
name | Field name | string | N |
type | Field type | string | N |
method | Rust resolver method name. If specified, name will not be camelCased in schema definition | string | Y |
desc | Field description | string | Y |
deprecation | Field deprecation reason | string | Y |
arg | Field arguments | [InterfaceFieldArgument] | Y |
external | Mark a field as owned by another service. This allows service A to use fields from service B while also knowing at runtime the types of that field. | bool | Y |
provides | Annotate the expected returned fieldset from a field on a base type that is guaranteed to be selectable by the gateway. | string | Y |
requires | Annotate the required input fieldset from a base type for a resolver. It is used to develop a query plan where the required fields may not be needed by the client, but the service may need additional information from other services. | string | Y |
visible | If false , it will not be displayed in introspection. See also the Book. | bool | Y |
visible | Call the specified function. If the return value is false , it will not be displayed in introspection. | string | Y |
Field argument parameters
Attribute | description | Type | Optional |
---|---|---|---|
name | Argument name | string | N |
type | Argument type | string | N |
desc | Argument description | string | Y |
default | Use Default::default for default value | none | Y |
default | Argument default value | literal | Y |
default_with | Expression to generate default value | code string | Y |
visible | If false , it will not be displayed in introspection. See also the Book. | bool | Y |
visible | Call the specified function. If the return value is false , it will not be displayed in introspection. | string | Y |
Define an interface
Define TypeA, TypeB, TypeC... Implement the MyInterface
ⓘ
#[derive(Interface)] enum MyInterface { TypeA(TypeA), TypeB(TypeB), TypeC(TypeC), ... }
Fields
The type, name, and parameter fields of the interface must exactly match the type of the implementation interface, but Result can be omitted.
use async_graphql::*; struct TypeA { value: i32, } #[Object] impl TypeA { /// Returns data borrowed from the context async fn value_a<'a>(&self, ctx: &'a Context<'_>) -> Result<&'a str> { Ok(ctx.data::<String>()?.as_str()) } /// Returns data borrowed self async fn value_b(&self) -> &i32 { &self.value } /// With parameters async fn value_c(&self, a: i32, b: i32) -> i32 { a + b } /// Disabled name transformation, don't forget "method" argument in interface! #[graphql(name = "value_d")] async fn value_d(&self) -> i32 { &self.value + 1 } } #[derive(Interface)] #[graphql( field(name = "value_a", type = "&'ctx str"), field(name = "value_b", type = "&i32"), field(name = "value_c", type = "i32", arg(name = "a", type = "i32"), arg(name = "b", type = "i32")), field(name = "value_d", method = "value_d", type = "i32"), )] enum MyInterface { TypeA(TypeA) } struct QueryRoot; #[Object] impl QueryRoot { async fn type_a(&self) -> MyInterface { TypeA { value: 10 }.into() } } async_std::task::block_on(async move { let schema = Schema::build(QueryRoot, EmptyMutation, EmptySubscription).data("hello".to_string()).finish(); let res = schema.execute(r#" { typeA { valueA valueB valueC(a: 3, b: 2) value_d } }"#).await.into_result().unwrap().data; assert_eq!(res, value!({ "typeA": { "valueA": "hello", "valueB": 10, "valueC": 5, "value_d": 11 } })); });