Introduction to REST API with Express.js

Express.js is a popular web application framework for Node.js, and it provides a powerful set of features for building RESTful APIs. In this article, we will explore the basics of building a REST API with Express.js.

What is REST API?

REST stands for Representational State Transfer, and it is an architectural style for building web services. REST APIs are designed to be stateless, meaning that each request from the client contains all the information needed to process the request. This makes REST APIs scalable and easy to maintain.

Building a REST API with Express.js

Express.js provides a simple and intuitive way to define routes for handling different HTTP methods such as GET, POST, PUT, and DELETE. These routes can be used to create, read, update, and delete resources in a RESTful manner.

Here’s a simple example of defining a REST API with Express.js:

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

// Define a route for getting all users
app.get('/users', (req, res) => {
  // Logic for fetching all users from the database
  res.send('Get all users');
});

// Define a route for creating a new user
app.post('/users', (req, res) => {
  // Logic for creating a new user in the database
  res.send('Create a new user');
});

// Define a route for updating a user
app.put('/users/:id', (req, res) => {
  // Logic for updating a user in the database
  res.send('Update user with id ' + req.params.id);
});

// Define a route for deleting a user
app.delete('/users/:id', (req, res) => {
  // Logic for deleting a user from the database
  res.send('Delete user with id ' + req.params.id);
});

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

In this example, we define routes for handling different HTTP methods for a /users resource. The routes handle GET, POST, PUT, and DELETE requests for fetching, creating, updating, and deleting users.

Conclusion

Express.js provides a convenient way to build RESTful APIs with Node.js. With its simple and expressive syntax, it is easy to create and maintain RESTful API endpoints for your web applications. If you’re looking to build a robust and scalable API, Express.js is a great choice.