IMPORTANT

GraQL is prerelease, experimental, and a demonstration piece. Use at your own risk.

Federation

What is Federation?

Federation allows you to publish multiple GraphQL APIs that work together as one. Multiple microservices, monoliths, or other architectures we haven't yet devised can "join" their schemas into one "superschema" with a single HTTP endpoint allowing access to multiple APIs.

How Do I Federate?

Easily! GraQL bundles Apollo's federation-jvm module, built on top of graphql-java. It does all of the heavy lifting.

All we need to do is add directives to our schema that state which types are entry points from the supergraph into our schema.

In this example, we're registering ToDo as such a type by adding the @key directive

type ToDo @key(fields: "id") { # <4>
    id: ID!
    title: String!
    completed: Boolean!
    dateCompleted: DateTime
    author: Author!
}

How Does This Work?

GraQL automatically registers any necessary DataFetchers and TypeResolvers needed by a federation router through its GraQLFederationProvider and GraQLFederatedEntityResolver classes.