1. Introduction

In this tutorial, our aim is to provide an understanding of how to effectively use REST and GraphQL together in a project. You will learn how to leverage the strengths of both to build efficient, robust applications. By the end of this tutorial, you will have a firm grasp of how to combine these two technologies in a way that maximizes the benefits of each.

Prerequisites:
- Basic knowledge of JavaScript and Node.js
- Familiarity with RESTful APIs and GraphQL

2. Step-by-Step Guide

Understanding REST and GraphQL

REST (Representational State Transfer) is a standard for designing APIs. It allows for easy communication with a server through basic HTTP methods like GET, POST, PUT, and DELETE.

GraphQL, on the other hand, is a query language for APIs. It provides a more efficient solution for fetching data by allowing the client-side to specify exactly what data it needs.

Using REST and GraphQL Together

While REST is great for simple, CRUD-based interactions, GraphQL shines when you need to fetch complex, nested data. Using them together allows you to optimize for both scenarios. You can use REST for simple requests and GraphQL for more complex ones.

3. Code Examples

REST API with Express.js

Here's a simple REST API using Express.js:

const express = require('express');
const app = express();

app.get('/hello', (req, res) => {
  res.send('Hello, world!');
});

app.listen(3000, () => {
  console.log('Server started on port 3000');
});

This code sets up a simple server with one GET endpoint at /hello, which responds with "Hello, world!".

GraphQL Server with Apollo Server

Now, let's set up a simple GraphQL server using Apollo Server:

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

const typeDefs = gql`
  type Query {
    hello: String
  }
`;

const resolvers = {
  Query: {
    hello: () => 'Hello, world!',
  },
};

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

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

This code sets up a simple GraphQL server with one query hello, which also responds with "Hello, world!".

4. Summary

In this tutorial, we learned about REST and GraphQL, their strengths, and how to use them together. We also looked at examples of creating a REST API with Express.js and a GraphQL server with Apollo Server.

Next, you can explore more complex examples, such as how to handle authentication, how to structure your code for maintainability, and how to handle errors.

5. Practice Exercises

Exercise 1: Create a REST API with Express.js that has CRUD operations for a resource of your choice.

Exercise 2: Create a GraphQL server with Apollo Server that has queries and mutations for a resource of your choice.

Exercise 3: Integrate the REST API and GraphQL server from the previous exercises.

Remember to practice, practice and practice. The more you code, the better you'll become.

Happy Coding!