How To Create a Simple HTTP Server in Node?

NodeJS is a powerful runtime environment that allows developers to build scalable and high-performance applications, especially for I/O-bound operations. One of the most common uses of NodeJS is to create HTTP servers.

What is HTTP?

HTTP (Hypertext Transfer Protocol) is a protocol used for transferring data across the web. It's the foundation of any data exchange on the Web and it allows browsers and servers to communicate. HTTP servers handle incoming requests from clients (typically web browsers), process them, and send back appropriate responses.

In NodeJS, the built-in http module makes it easy to create an HTTP server that can handle these requests.

Steps to Create a NodeJS Server

To create a simple HTTP server in NodeJS, follow these steps:

Step 1: Initialize the Project

Begin by initializing your project using npm, which will create a package.json file to manage your project's dependencies and configurations.

npm init -y

Step 2: Import the HTTP Module

NodeJS includes a built-in HTTP module that allows you to create an HTTP server.

const http = require('http');

Step 3: Create a Server

Use the http.createServer() method to create an HTTP server. This method accepts a callback function that handles incoming requests and sends responses.

const server = http.createServer((request, response) => {
    // Request handling logic
});

Step 4: Handle Requests

Within the server, set the response header and body to define how the server responds to incoming requests.

const server = http.createServer((request, response) => {
    response.writeHead(200, { 'Content-Type': 'text/plain' });
    response.end('Hello, World!\n');
});

Example: After implementing the above steps, we will effectively establish the NodeJS server

const http = require('http');
const server = http.createServer((request, response) => {
    response.writeHead(200, { 'Content-Type': 'text/plain' });
    response.end('Hello, GeeksforGeeks!\n');
});
const PORT = 3000;
server.listen(PORT, () => {
    console.log(`Server running at http://localhost:${PORT}/`);
});

• Loading the http Module: The http module is required to create an HTTP server.
• Creating the Server: The createServer method is used to create the server, which takes a callback function that handles incoming requests and sends responses.
• Setting Response Headers and Body: The writeHead method sets the HTTP status code and headers, while the end method sends the response body.
• Starting the Server: The listen method starts the server on the specified port and IP address, and a callback function logs a message when the server is running.

Terminal Output: When you start the server, you'll see:

Web Browser Output: When you access http://localhost:3000/ in your web browser, the server responds with

Now a simple HTTP server is created. You can enhance it to handle more complex use cases like CRUD operations etc.