Express.js and WebSockets

WebSockets provide a way to open a persistent connection between a client and server, allowing for real-time, bidirectional communication. This guide covers key concepts, examples, and best practices for using WebSockets in Express.js applications.

Key Concepts of WebSockets

• WebSocket: A protocol that provides full-duplex communication channels over a single TCP connection.
• Persistent Connection: WebSockets maintain an open connection between the client and server, allowing for continuous data exchange.
• Real-Time Communication: Enables instant communication between clients and servers.

Setting Up WebSockets

Integrate WebSockets with an Express.js server using the ws library:

Example: Basic Setup

// Install the ws library
// npm install ws

// server.js
const express = require('express');
const http = require('http');
const WebSocket = require('ws');
const app = express();
const server = http.createServer(app);
const wss = new WebSocket.Server({ server });

app.get('/', (req, res) => {
    res.sendFile(__dirname + '/index.html');
});

wss.on('connection', (ws) => {
    console.log('A new client connected');

    ws.on('message', (message) => {
        console.log(`Received message: ${message}`);
    });

    ws.on('close', () => {
        console.log('Client disconnected');
    });
});

server.listen(3000, () => {
    console.log('Server running at http://localhost:3000/');
});

// index.html



    


    
WebSocket Example