GraphQL subscriptions require a bit more resources than regular queries and provide a great vector for DoS attacks. This can can bring down a server easily if not handled correctly. The SubscriptionCoordinator trait provides coordination logic to enable functionality like DoS attacks mitigation and resource limits.
The SubscriptionCoordinator contains the schema and can keep track of opened connections, handle subscription start and end, and maintain a global ID for each subscription. Each time a connection is established, the SubscriptionCoordinator spawns a [32], which handles a single connection, providing resolver logic for a client stream as well as reconnection and shutdown logic.
While we can implement SubscriptionCoordinator ourselves, Juniper contains a simple and generic implementation called Coordinator. The subscribe method returns a Future resolving into a Result<Connection, GraphQLError>, where Connection is a Stream of values returned by the operation, and a GraphQLError is the error when the subscription operation fails.
While we can implement SubscriptionCoordinator ourselves, Juniper contains a simple and generic implementation called Coordinator. The subscribe method returns a Future resolving into a Result<Connection, GraphQLError>, where Connection is a Stream of values returned by the operation, and a GraphQLError is the error when the subscription operation fails.
extern crate futures; extern crate juniper; extern crate juniper_subscriptions; diff --git a/schema/subscriptions.html b/schema/subscriptions.html index 8ad9ae15..413eb462 100644 --- a/schema/subscriptions.html +++ b/schema/subscriptions.html @@ -220,7 +220,7 @@ impl Subscription {Coordinator
GraphQL subscriptions require a bit more resources than regular queries and provide a great vector for DoS attacks. This can can bring down a server easily if not handled correctly. The
SubscriptionCoordinatortrait provides coordination logic to enable functionality like DoS attacks mitigation and resource limits.The
-SubscriptionCoordinatorcontains the schema and can keep track of opened connections, handle subscription start and end, and maintain a global ID for each subscription. Each time a connection is established, theSubscriptionCoordinatorspawns a [32], which handles a single connection, providing resolver logic for a client stream as well as reconnection and shutdown logic.While we can implement
+SubscriptionCoordinatorourselves, Juniper contains a simple and generic implementation calledCoordinator. Thesubscribemethod returns aFutureresolving into aResult<Connection, GraphQLError>, whereConnectionis aStreamof values returned by the operation, and aGraphQLErroris the error when the subscription operation fails.While we can implement
SubscriptionCoordinatorourselves, Juniper contains a simple and generic implementation calledCoordinator. Thesubscribemethod returns aFutureresolving into aResult<Connection, GraphQLError>, whereConnectionis aStreamof values returned by the operation, and aGraphQLErroris the error when the subscription operation fails.extern crate futures; extern crate juniper; extern crate juniper_subscriptions;