Making a client GRPC call with grpcbox from elixir

I need to be able to build grpc streaming clients and servers in an elixir app. For example, to be able to have an elixir client subscribe for changes via grpc to a grpc server, and vice-versa … to build server-side grpc-based subscription services in elixir that can notify grpc clients of updates to their subscriptions.

The grpc package has streams listed as “todo”. The grpcbox erlang package based on chatterbox seems to have strong support for streaming. And although it’s erlang, I’ve got an elixir umbrella app that starts grpcbox with my proto-generated services running and accepting requests.

I haven’t figured out how to make outbound client grpc calls with grpcbox. The examples seem to expect that you’ve already made a connection to the target server. But how to do that?

Does anyone have any examples of establishing a connection using chatterbox/grpcbox and then sending requests and receiving streamed responses over that connection?