Rest based services in back-end

Question

we build a 30M+ users' online community, which has RESTful services in it's back-end and a front-end which utilizes them. My concern is: Is it OK to use REST as internal data transfer protocol, or it will significantly drop the performance, compared with Java's binary serialization protocol (language dependent)? What other approaches/protocols can be used to keep it language independent and maximally fast?

Answer 1

The REST approach can be quite ok, but the http layer can slow things down. If your use REST in the back-end, your should make sure that the connection between your back-end and front-end is kept open and not reopened with every request.

More details about http keep-alive can be found here: http://en.wikipedia.org/wiki/HTTP_persistent_connection

Answer 2

One advantage that REST gives you between front- and back-end layers is the flexibility to add a layer of HTTP caching in between to boost the performance without needing to modify the either of the existing layers. The same holds true for load-balancing for scaling out the back-end, since HTTP load-balancers are very well understood and easy to deploy.

These two benefits of REST can result in a major benefit over more traditional RPC serialization techniques, depending on the situation, especially if you have "slow" back-end processes that can benefit from caching or being load-balanced.

The other place REST wins out is if you need to expand the client base using the back-end services (which I think you hinted at with the desire for language independence). No only does a REST-based service layer allow you to intermingle client languages freely, but it also allows you to easily open up your API to 3rd-party developers with almost no extra effort. Having a platform for others to build on has proven to be wildly successful as a business model and it never hurts to keep your development as open and flexible as possible.