@apollo/gateway

What is @apollo/gateway?

@apollo/gateway is a package that allows you to build a federated data graph by composing multiple GraphQL services into a single unified API. It is part of Apollo's Federation architecture, which enables you to manage and scale your GraphQL services independently while providing a seamless experience for clients.

What are @apollo/gateway's main functionalities?

Creating a Gateway

This code sample demonstrates how to create an Apollo Gateway that composes multiple GraphQL services into a single unified API. The `serviceList` array contains the list of services to be federated.

const { ApolloGateway } = require('@apollo/gateway');
const { ApolloServer } = require('apollo-server');

const gateway = new ApolloGateway({
  serviceList: [
    { name: 'accounts', url: 'http://localhost:4001' },
    { name: 'products', url: 'http://localhost:4002' },
    { name: 'reviews', url: 'http://localhost:4003' }
  ]
});

const server = new ApolloServer({ gateway, subscriptions: false });

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

Customizing Service Health Checks

This code sample shows how to enable service health checks in Apollo Gateway. The `serviceHealthCheck` option ensures that the gateway periodically checks the health of the federated services.

const { ApolloGateway } = require('@apollo/gateway');
const { ApolloServer } = require('apollo-server');

const gateway = new ApolloGateway({
  serviceList: [
    { name: 'accounts', url: 'http://localhost:4001' },
    { name: 'products', url: 'http://localhost:4002' },
    { name: 'reviews', url: 'http://localhost:4003' }
  ],
  serviceHealthCheck: true
});

const server = new ApolloServer({ gateway, subscriptions: false });

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

Using Managed Federation

This code sample demonstrates how to use managed federation with Apollo Gateway. The `experimental_pollInterval` option allows the gateway to periodically poll for updates to the federated services' schemas.

const { ApolloGateway } = require('@apollo/gateway');
const { ApolloServer } = require('apollo-server');

const gateway = new ApolloGateway({
  serviceList: [
    { name: 'accounts', url: 'http://localhost:4001' },
    { name: 'products', url: 'http://localhost:4002' },
    { name: 'reviews', url: 'http://localhost:4003' }
  ],
  experimental_pollInterval: 10000
});

const server = new ApolloServer({ gateway, subscriptions: false });

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

Other packages similar to @apollo/gateway

graphql-tools

graphql-tools is a package that provides a set of utilities to build and manipulate GraphQL schemas in JavaScript. It allows you to create a unified schema from multiple GraphQL services, similar to Apollo Gateway. However, it does not provide the same level of built-in support for federated services and managed federation as Apollo Gateway.

graphql-mesh

graphql-mesh is a package that allows you to create a unified GraphQL schema from multiple sources, including REST APIs, gRPC services, and other GraphQL APIs. It provides a flexible and extensible way to integrate different data sources into a single GraphQL API. Compared to Apollo Gateway, graphql-mesh offers more versatility in terms of the types of data sources it can integrate, but it may require more configuration and setup.

README

Apollo Gateway