Implementing a gRPC push service

[John Coffey]

What is the right  approach to implement a push service with gRPC?  

My server listens for updates from an external network (basically a background thread) and the service needs to push these updates as they arrive to a listening client (if it is currently connected)  - This is just a very basic listener/observer type of pattern.

I was trying to use the asynchronous API to implement this, but it is overly complex and there are only 2 c++ examples.  Are there any examples similar to what I describe above?

Thanks in advance