const express = require('express'); const app = express(); const http = require('http').Server(app); const io = require('socket.io')(http); const port = process.env.PORT || 3000; app.use(express.static(__dirname + '/public')); function onConnection(socket){ socket.on('key', (data) => socket.broadcast.emit('key', data)); socket.on('slidesLen', (data) => socket.broadcast.emit('slidesLen', data)); } io.on('connection', onConnection); http.listen(port, () => console.log('listening on port ' + port));