So it looks like UPS is using a jar packaged by "theganyo" https://github.com/theganyo/gcm-server for its Google stuff. This appears to be a fork of Google's GCM code which was put into maven central. It is also about two years out of date.
For implementing topic support I am probably going to need some functionality from Google's actual code. Even if I don't I am going to need things feature in neither repository (Constants for error messages in response to topic messaging are immediately apparent).
I am looking for brainstorming around the best way to gracefully move this functionality forward. I'm thinking drop the ganyo dependency and code and pull the current Google code into UPS. It is apache licensed.
Thoughts, fears, tomatoes?
Summers