Node http Module Tutorial

The Node.js HTTP module is a core module that allows you to create HTTP servers and clients.

In this tutorial, you will learn http module in node with examples.

Introduction to the HTTP Module

The HTTP module in Node.js provides functionality to create HTTP servers and clients.
It is commonly used to build web servers and make HTTP requests to other servers.

Creating an HTTP Server

To create an HTTP server, you need to require the http module and use its createServer method.
You must provide a callback function that will be called for each incoming request.

const http = require('http');

const server = http.createServer((req, res) => {
    // Handle the request here
});

const port = 3000;
server.listen(port, () => {
    console.log(`Server is listening on port ${port}`);
});

Handling HTTP Requests

The req object represents the HTTP request and contains information about the client's request.
You can access properties like req.url, req.method, and req.headers to examine the request.

Sending HTTP Responses

The res object is used to send an HTTP response to the client.
You can set response headers, status codes, and send a response body using methods like res.setHeader(), res.statusCode, and res.end().

const server = http.createServer((req, res) => {
    res.statusCode = 200;
    res.setHeader('Content-Type', 'text/plain');
    res.end('Hello, world!\n');
  });

Parsing Request Data

To work with data sent in the request, you may need to parse it.
Commonly used data formats include URL parameters and request bodies

const server = http.createServer((req, res) => {
    // Parse URL parameters
    const urlParams = new URL(req.url, `http://${req.headers.host}`);
    const queryData = urlParams.searchParams.get('data');
  
    // Read request body
    let body = '';
    req.on('data', (chunk) => {
      body += chunk;
    });
  
    req.on('end', () => {
      console.log('URL Parameter:', queryData);
      console.log('Request Body:', body);
      res.end('Data received');
    });
  });

Making HTTP Requests as a Client

The HTTP module can be used to make HTTP requests to other servers as a client.
The http.get() and http.request() methods are commonly used to initiate requests.

const http = require('http');

    const options = {
      hostname: 'example.com',
      path: '/api/data',
      method: 'GET',
    };
    
    const req = http.request(options, (res) => {
      let data = '';
    
      res.on('data', (chunk) => {
        data += chunk;
      });
    
      res.on('end', () => {
        console.log(data);
      });
    });
    
    req.end();

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