Socket.io and ajax request to php page

Question

I'm setting up a realtime app that will be using socket.io. There's currently some core functionally in php, that utilizes memcache and mysql backend.

Would it make sense in the socket.io server to do an ajax request (if that's even possible) to the php page that handles this? There's a lot of MySQL querying, I know it can be done in node.js, but I'd rather keep this part abstracted in php if possible.

So, my question is, is that a proper thing to do? Call a php page from within the socket.io server to then return to the client?

Thanks!

Answer 1

I don't see any problems with having your node.js app communicate with your PHP app by exposing a RESTful API or some PHP script that you can POST to or GET from your socket.io node.js server. There are plenty of npm modules (like request ) that can make HTTP requests like that a breeze for you. After retrieving the data from PHP in your node app, you can use socket.io to emit() the data to the socket.io client on the frontend.

Answer 2

There is nothing wrong with that. You are simply using a RESTful API to access the MySQL data, thus isolating the database details.

If one day you are tired of PHP, you can easily switch to Ruby, Python or Whatever for that part without even touching the node.js. If your logic is already written in PHP (you are upgrading an old app), it make even more sense as you can reuse what has already been tested and debugged. A lot of folks are advocating for that kind of separation between systems. Just look at all the SOA (Service Oriented Architecture) buzz.

Where I work we are using this very architecture in a project (though in this case its an ASP.NET MVC Website calling a Java EE app) and it served us very well. With the event model of node.js, its even better since you won't block waiting for the PHP.

But of course, there are some drawback

• Performance overhead
• Architecture is more complicated
• You now work with two language instead of only one (though javascript and PHP are so often used together that I don't think it's really is a problem in this case)

So you need to ask yourself if your problem really need that solution. But in a lot of case the answer may be yes. Just don't forget the virtue of Keeping It Simple and Stupid (the KISS principle)