💡

This is the documentation for the old GraphQL Yoga version 2. We recommend upgrading to the latest GraphQL Yoga version 3.

Get started with GraphQL Yoga v3

Apollo Federation

Apollo Federation is a specification that applies microservice architecture through GraphQL APIs.

Thanks to Envelop's Apollo Federation plugin, we can use GraphQL Yoga to build our gateway server.

💡

As documented in the Apollo Federation docs, @apollo/gateway package doesn't support GraphQL v16 so you have to install graphql@15.

💡

Please note that Apollo Federation implementation doesn't support GraphQL Subscriptions. If you need to use Subscriptions with a Federated Gateway you can use Schema Stitching.

Gateway

Installation for Gateway

yarn add @graphql-yoga/node @apollo/gateway @envelop/apollo-federation graphql@15

Example Gateway

import { createServer } from '@graphql-yoga/node'
import { ApolloGateway, RemoteGraphQLDataSource } from '@apollo/gateway'
import { useApolloFederation } from '@envelop/apollo-federation'
 
/**
 * Needed since federation remote data source fetcher
 * doesn't support `application/graphql-response+json` content type
 * https://github.com/apollographql/federation/issues/2161
 * And yoga defaults to `application/graphql-response+json` as per the spec.
 */
class DataSource extends RemoteGraphQLDataSource {
  willSendRequest({ request }) {
    request.http.headers.set('accept', 'application/json')
  }
}
 
// Initialize the gateway
const gateway = new ApolloGateway({
  serviceList: [
    { name: 'accounts', url: 'http://localhost:4001' },
    { name: 'products', url: 'http://localhost:4002' }
    // ...additional subgraphs...
  ],
  introspectionHeaders: {
    accept: 'application/json'
  },
  buildService({ url }) {
    return new DataSource({ url })
  }
})
 
// Make sure all services are loaded
await gateway.load()
 
const server = createServer({
  plugins: [useApolloFederation({ gateway })]
})
 
// Start the server and explore http://localhost:4000/graphql
server.start()

Federation Service

You don't need any extra plugins for Yoga for Federation Service.

Installation

yarn add @graphql-yoga/node @apollo/subgraph graphql

Example User Service

const { parse } = require('graphql')
const { buildSubgraphSchema } = require('@apollo/subgraph')
const { createServer } = require('@graphql-yoga/node')
 
const typeDefs = parse(/* GraphQL */ `
  type Query {
    me: User
  }
 
  type User @key(fields: "id") {
    id: ID!
    username: String
  }
`)
 
const resolvers = {
  Query: {
    me() {
      return { id: '1', username: '@ava' }
    }
  },
  User: {
    __resolveReference(user, { fetchUserById }) {
      return fetchUserById(user.id)
    }
  }
}
const server = createServer({
  schema: buildSubgraphSchema([{ typeDefs, resolvers }]),
  port: 4001
})
 
server.start().then(() => {
  console.log(`🚀 Server ready at http://localhost:4001`)
})

Working Example

Check our working example to try it out.

Last updated on November 15, 2022

Testing CORS