app.js

const express = require('express');
const app = express();
const http = require('http').createServer(app);
const path = require('path');
const io = require('socket.io')(http);
const port = 4000;

function uuid() {
    return "xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx".replace(/[xy]/g, (c) => {
        var r = (Math.random() * 16) | 0,
            v = c == "x" ? r : (r & 0x3) | 0x8;
        return v.toString(16);
    });
}

app.use(express.static(path.join(__dirname, 'src')));
// console.log(path.join(__dirname, 'public','index.html'))
app.get('/', (req, res) => {
    res.sendFile(path.join(__dirname, 'public', 'index.html'))
});

io.on('connection', (socket) => {
    let id = socket.client.conn.id;
    console.log(`(User: ${id}) connected`);
    socket.on('chat-message', (msg) => {
        socket.broadcast.emit('chat-message', {
            body: msg,
            id: uuid(),
            type: 'recipient'
        })
    });
    socket.on('is-typing', () => {
        socket.broadcast.emit('is-typing');
    });
    socket.on('not-typing', () => {
        socket.broadcast.emit('not-typing');
    });
    socket.on('disconnect', () => {
        console.log(`(User: ${id}) disconnected`);
    });
});

http.listen(port, () => {
    console.log('Server running on port ' + port)
})