Server Socket Broadcast

Video Lecture

Server Socket Broadcast Server Socket Broadcast

Description

Broadcast a message to all other connected sockets except for itself. Used most often after a socket level event occurs, eg, a new message arrived on an existing client socket.

img/server-broadcast-emit.jpg

src/server/server.ts

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import express from "express"
import path from "path"
import http from "http"
import socketIO from "socket.io"

const port: number = 3000

class App {
    private server: http.Server
    private port: number

    private io: socketIO.Server

    constructor(port: number) {
        this.port = port

        const app = express()
        app.use(express.static(path.join(__dirname, '../client')))

        this.server = new http.Server(app)
        this.io = socketIO(this.server);

        this.io.on('connection', (socket: socketIO.Socket) => {
            console.log('a user connected : ' + socket.id)

            socket.emit("message", "Hello " + socket.id);

            socket.broadcast.emit("message", "Everybody, say hello to " + socket.id);

            socket.on('disconnect', function () {
                console.log('socket disconnected : ' + socket.id);
            });   
        })
    }

    public Start() {
        this.server.listen(this.port)
        console.log( `Server listening on port ${this.port}.` )
    }
}

new App(port).Start()

src/client/client.ts

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class Client {
    private socket: SocketIOClient.Socket

    constructor() {
        this.socket = io();

        this.socket.on("message", function (message: any) {
            console.log(message)
            document.body.innerHTML += message + "<br/>"
        })
    }
}

const client = new Client();