// Setup basic express server var express = require('express'); var app = express(); var server = require('http').createServer(app); var io = require('socket.io')(server); var port = process.env.PORT || 8080; server.listen(port, function () { console.log('Server listening at port %d', port); }); // Routing app.use(express.static(__dirname + '/public')); // Chatroom var numUsers = 0; io.on('connection', function (socket) { var addedUser = false; // when the client emits 'new message', this listens and executes socket.on('new message', function (data) { // we tell the client to execute 'new message' socket.broadcast.emit('new message', { username: socket.username, message: data }); }); // when the client emits 'add user', this listens and executes socket.on('add user', function (username) { if (addedUser) return; // we store the username in the socket session for this client socket.username = username; ++numUsers; addedUser = true; socket.emit('login', { numUsers: numUsers }); // echo globally (all clients) that a person has connected socket.broadcast.emit('user joined', { username: socket.username, numUsers: numUsers }); }); // when the client emits 'typing', we broadcast it to others socket.on('typing', function () { socket.broadcast.emit('typing', { username: socket.username }); }); // when the client emits 'stop typing', we broadcast it to others socket.on('stop typing', function () { socket.broadcast.emit('stop typing', { username: socket.username }); }); // when the user disconnects.. perform this socket.on('disconnect', function () { if (addedUser) { --numUsers; // echo globally that this client has left socket.broadcast.emit('user left', { username: socket.username, numUsers: numUsers }); } }); });