Express.js and Socket.io

Socket.io is a library that enables real-time, bidirectional, and event-based communication between web clients and servers. This guide covers key concepts, examples, and best practices for using Socket.io in Express.js applications.

Key Concepts of Socket.io

• Real-Time Communication: Enables instant communication between clients and servers.
• Event-Based: Communication is based on custom events emitted and listened to by clients and servers.
• Bidirectional: Supports two-way communication between clients and servers.

Setting Up Socket.io

Integrate Socket.io with an Express.js server:

Example: Basic Setup

// server.js
const express = require('express');
const http = require('http');
const socketIo = require('socket.io');
const app = express();
const server = http.createServer(app);
const io = socketIo(server);

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

io.on('connection', (socket) => {
    console.log('a user connected');
    socket.on('disconnect', () => {
        console.log('user disconnected');
    });
});

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

// index.html



    


    
Socket.io Example