Attribute Macro async_graphql::ComplexObject[][src]

#[ComplexObject]
Expand description

Define a complex GraphQL object for SimpleObject’s complex field resolver.

See also the Book.

Sometimes most of the fields of a GraphQL object simply return the value of the structure member, but a few fields are calculated. Usually we use the Object macro to define such a GraphQL object.

But this can be done more beautifully with the ComplexObject macro. We can use the SimpleObject macro to define some simple fields, and use the ComplexObject macro to define some other fields that need to be calculated.

Macro parameters

AttributedescriptionTypeOptional
nameObject namestringY
rename_fieldsRename all the fields according to the given case convention. The possible values are “lowercase”, “UPPERCASE”, “PascalCase”, “camelCase”, “snake_case”, “SCREAMING_SNAKE_CASE”.stringY
rename_argsRename all the arguments according to the given case convention. The possible values are “lowercase”, “UPPERCASE”, “PascalCase”, “camelCase”, “snake_case”, “SCREAMING_SNAKE_CASE”.stringY

Field parameters

AttributedescriptionTypeOptional
skipSkip this fieldboolY
nameField namestringY
deprecationField deprecatedboolY
deprecationField deprecation reasonstringY
cache_controlField cache controlCacheControlY
externalMark 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.boolY
providesAnnotate the expected returned fieldset from a field on a base type that is guaranteed to be selectable by the gateway.stringY
requiresAnnotate 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.stringY
guardField of guardGuardY
visibleIf false, it will not be displayed in introspection. See also the Book.boolY
visibleCall the specified function. If the return value is false, it will not be displayed in introspection.stringY
secretMark this field as a secret, it will not output the actual value in the log.boolY

Examples

use async_graphql::*;

#[derive(SimpleObject)]
#[graphql(complex)] // NOTE: If you want the `ComplexObject` macro to take effect, this `complex` attribute is required.
struct MyObj {
    a: i32,
    b: i32,
}

#[ComplexObject]
impl MyObj {
    async fn c(&self) -> i32 {
        self.a + self.b     
    }
}

struct QueryRoot;

#[Object]
impl QueryRoot {
    async fn obj(&self) -> MyObj {
        MyObj { a: 10, b: 20 }
    }
}

tokio::runtime::Runtime::new().unwrap().block_on(async move {
    let schema = Schema::new(QueryRoot, EmptyMutation, EmptySubscription);
    let res = schema.execute("{ obj { a b c } }").await.into_result().unwrap().data;
    assert_eq!(res, value!({
        "obj": {
            "a": 10,
            "b": 20,
            "c": 30,
        },
    }));
});