Google Feed API V2 aka push vs Channel API vs WebSocket

Question

Does anybody knows when will feed v2 leave trusted tester stage? There are some usecases of feed v2 that overlap with Google Channel API, so I don't quite get point of releasing feed v2, instead of switching to channel API entirely. Is this due to smoother transition towards Web Socket API ? or I miss some point :)

Answer 1

I don't have any data on when Feeds V2 will leave trusted tester, but the use cases are fairly discrete:

Generally:

• Feeds API is for when you want realtime data from existing sources you don't control, or want to deliver messages to lots and lots of clients, some of whom may be listening using the Feeds API, some of whom may retrieve the data statically, etc.

• Channel API is for applications that want to deliver particular messages to one specific client. The Channel API could be used as an implementation of a piece of the Feeds API (though it isn't, now) but it wouldn't encompass it.

Other than that, latency will generally be lower with the Channel API (at heart, because it's bound to one client).