php - Real time notification from web server to client bowers

Question

I am developing an appointments center web application using php+mysql. what I currently trying to do is to send notification when an appointment has been made from web server to client/user bowers without third party pushers and without using jQuery SetInterval AJAX request. I think SetInterval & AJAX is a bad approach because there would be too much traffic between the client and the server.

How can I implement notifications without polling the server with SetInterval?

Answer 1

You can do this using NodeJs. NodeJS is javascript on your server that pushes content to connected clients in real time.

Its really easy to use and setup. You need a server dedicated to the real time app, I use http://nodejitsu.com.

Server Side

var app = require('http').createServer(handler)
, io = require('socket.io').listen(app)
, url = require('url')

app.listen(8080);

function handler (req, res) {
// parse URL
var requestURL = url.parse(req.url, true);

// if there is a message, send it
if(requestURL.query.message)
    sendMessage(decodeURI(requestURL.query.message));

// end the response
res.writeHead(200, {'Content-Type': 'text/plain'});
res.end("");
}

function sendMessage(message) {
io.sockets.emit('notification', {'message': message});
}

Client Side

<script src="socket.io.min.js"></script>
<script>
var socket = io.connect('http://localhost:8080');
socket.on('notification', function (data) {
    console.log(data.message);
});
</script>

I added the easy to use example by @intivev below to complete the answer for future readers