apollo-server/docs/source/migration-engine.md

title	description
Using Engine with v2.0 RC	How to use Engine with Apollo Server 2.0 RC

Apollo Server provides reporting and persisted queries in native javascript by default, so often times moving to Apollo Server 2 without the Engine proxy is possible. For services that require the Engine proxy, Apollo Server continues to support with first class functionality. With Apollo Server 2, the engine proxy can be started by the same node process. If Engine is running in a dedicated machine, Apollo Server 2 supports the cache-control and tracing extensions, used to communicate with the proxy.

Stand-alone Apollo Server

With ENGINE_API_KEY set as an environment variable, Apollo Server creates a reporting agent that sends execution traces to the Engine UI. In addition by default, Apollo Server supports persisted queries.

const { ApolloServer } = require('apollo-server');

const server = new ApolloServer({
  typeDefs,
  resolvers,
});

server.listen().then(({ url }) => {
  console.log(`🚀 Server ready at ${url}`);
});

Starting Engine Proxy

The apollo-engine package provides integrations with many node frameworks, including express, that starts the Engine Proxy alongside the framework. The following code demonstrates how to start the proxy with Apollo Server 2, assuming that the ENGINE_API_KEY environment variable is set to the api key of the service.

const { ApolloEngine } = require('apollo-engine');
const { ApolloServer } = require('apollo-server-express');
const express = require('express');

const app = express();
const server = new ApolloServer({
  typeDefs,
  resolvers,
  tracing: true,
  cacheControl: true
});

server.applyMiddlware({ app });

const engine = new ApolloEngine({
  apiKey: process.env.ENGINE_API_KEY,
});

engine.listen({
  port: 4000,
  graphqlPaths: ['/api/graphql'],
  expressApp: app,
  launcherOptions: {
    startupTimeout: 3000,
  },
}, () => {
  console.log('Listening!');
});

With a Running Engine Proxy

If the engine proxy is already running in a container in front of Apollo Server, then set tracing and cacheControl to true. These options will provide the extensions information to the proxy to create traces and ensure caching.

const { ApolloServer } = require('apollo-server');

const server = new ApolloServer({
  typeDefs,
  resolvers,
  tracing: true,
  cacheControl: true
});

server.listen().then(({ url }) => {
  console.log(`🚀 Server ready at ${url}`);
});