I'm developing a web application with Symfony2. I need to create a push notifications sysmte (like Facebook). When an user publish something, I need some of another users receive a notification.
I saw that Node.js it's the easiest manner to do this. But, I did some simple examples and all works fine, but I don't know how can I integrate this node.js application with my Symfony2 application, or really with a PHP application.
Anybody can help me?
Thanks in advance!
Please note that you've not given enough details, so I will respond as a front-end developer and not as a mobile developer
Integrating NodeJS and PHP (in general) is not a good way since you need to launch both servers separatly, create the websocket server in JS while your application is in PHP and finally create a request (GET or POST) from your PHP to you JS server. Well, a big mess, so I'll expose my solution here under.
Quick insight for mobile apps. Well, technically, there's no easy way. You can use the Push "protocol" (http://www.wikiwand.com/en/Push_technology) with NotificationPusher (https://github.com/Ph3nol/NotificationPusher). I didn't used it before so I can't help you with it.
In general. Most of the time when people thinks of Push, long polling will do the trick. For starters it means that the request is made client-side and the server don't send data & close connection until there's new data.
How do you implement this ?!? Basically, you change the max_execution_time using ini_set or set_time_limit to a very long time for the current script and launch a loop (like a do..while) with a sleep and the check to your data inside. From your Javascript just make an Ajax call, for example with jquery: $.get. Just remember to remove the timeout and stay in asynchronous mode.
The only drawback of this solution is that you will always have a connection opened to your server which will consume a bit more of battery on a mobile device. If you have multiple types of data to receive do not hesitate to merge the calls and publish a type in your response data, since most of the browsers allows only 2 or 3 simultaneous connections to the same server.
I sounds like your describing WebSockets.
Take a look at Socket.io, its a module for node.js.
Also there is a example at GitHub https://github.com/Automattic/socket.io/tree/master/examples/chat
Interesting files for you should be the index.js and the public/main.js.
You can see the example live at http://socket.io/demos/chat/
