What is the most efficient way to send OData payloads over the wire? “Dense JSON?”

Question

I'm designing a distributed application that will consist of a variety of REST services. Lately I've been going back and forth about whether to implement my REST services using the ASP.NET MVC 4 Web API or OData. Web API seems like it will some day be what I need but right now it's only half baked. Specifically, it only has a partial implementation of OData-style URI querying and doesn't do hypermedia out-of-the-box.

So this forces me to take another long hard look at OData. I really like the URI querying capability and structural hypermedia for lazy loading; I think I will use these features a lot in my application. However, the Atom Pub specification appears to be grossly inefficient.

I recently read a post about an efficient format for OData which mentions "dense JSON" but such a thing does not appear to actually exist. Is this true? And even if there's no such thing as dense JSON, regular JSON is still much more efficient than Atom Pub, correct?

Is there any situation where I would want to use Atom Pub over JSON?

Answer 1

There should be very little difference between ATOM and JSON on the semantic level with OData. Also most OData servers (WCF Data Services for sure) support both, so it's a choice of the client which one to use. As the blog post from Pablo mentions, to get the best payload size you should enable HTTP compression. It works great on both ATOM and JSON.

Reading JSON tends to be faster (XML parsing is kind of expensive), but that's if you're concerned with CPU consumption on the client. If I remember correctly, last time I saw the numbers, the compressed payload size for ATOM and JSON is not that different.

ATOM PUB is usually easier to consume in client which has available good XML or ATOM libraries and not JSON. And vice versa. But other than that, there should not be much of a difference.