Java Serverside flow control with ServerCallStreamObserver

[dan....@rach.io]

I am playing around with the experimental flow control functionality in ServerCallStreamObserver.

My goal is to wire up bi-directional calls into RxJava pipelines.  For the most part gRPC and Rx wire together easily.  If you are interested, my very initial setup is here: https://gist.github.com/oillio/75ffadfd44c30497a4e8cf6476eff438

I've got a couple questions on how flow control works.

From what I can see, the request-side flow control is actually managed through the passed in responseObserver object.

In order to take control, I should do something along the lines of:

((CallStreamObserver) responseObserver).disableAutoInboundFlowControl();

Then, I can request additional messages through:

((CallStreamObserver) responseObserver).request(1);

Is this the recommended way to do this?

Is there a way, or plans to provide a way, to manage flow control through the request StreamObserver returned by the application code handler?

This is a bit awkward for my use case as my request StreamObserver will need to keep a reference to the response StreamObserver in order to manage the request-side flow control.

[bornet...@gmail.com]

Hi,

I'm also very interested in wiring gRPC to rxJava's Flowable to get non-blocking back-pressure . Did you manage to make it work ?
It should also be possible to do it on the client side. Did you have a look ?

[Carl Mastrangelo]

Can you make a shared object between the two observers to control flow between the two?  That way they don't need a ref to each other?