How to create an event driven AJAX counter in Rails 3?

I have a simple User ActiveR开发者_运维百科ecord model class and I need to update a user counter visible in all pages (a partial) each time a new User is created. It should basically look like the download counter for Firefox here. I can imagine writing some JavaScript code that constantly polls the db would do the trick, but I guess that there is some better way to do it. I generally do mostly server-side programming and many UI techniques are quite new to me.

I'm using Rails 3.0.7 with jQuery enabled. I thank you in advance for suggestions/solutions to my predicament.

You could if you want use some kind of WebSockets solution. Which means that you can push the data whenever a new User is created to all the clients, and then just use JQuery to render the Counter area with the new data.

There's also 3rd party apps that makes this push technology really easy to set up. http://pusher.com/ is one of them.

If you want to investigate Node.js there's also Socket.io.

All of these "custom" solutions uses some kind of fallback because WebSockets isn't available in all web browsers. It usually is fallback to Flash Sockets or maybe Long polling.