Type Definition warpgrapher::engine::events::BeforeMutationEventFunc
source · [−]pub type BeforeMutationEventFunc<RequestCtx> = fn(_: Value, _: EventFacade<'_, RequestCtx>) -> BoxFuture<'_, Result<Value, Error>>;
Expand description
Type alias for a function called before a mutation event. The Value returned by this function will be used as the input to the next before event function, or to the base Warpgrapher resolver if there are no more before event functions.
The structure of Value
depends on the type of CRUD operation (which can be accessed via the op()
method on EventFacade
.) based on the list below:
CreateNode - Type>CreateMutationInput
UpdateNode - <Type>UpdateInput
DeleteNode - <Type>DeleteInput
You can refer to the generated GraphQL schema documentation for the data structures.
Examples
fn before_user_create(value: Value, ef: EventFacade<()>) -> BoxFuture<Result<Value, Error>> {
Box::pin(async move {
// Normally work would be done here, resulting in some new value.
Ok(value)
})
}