Cannot cancel Server streaming RPC from GRPC.Stub

[AleksandarFilipov]

Before I populate this as a proper bug,

The following is not working, and I suspect it's a bug, please enlighten me.

here is the failing test, which uses GRPC.Stub.cancel
https://github.com/elixir-grpc/grpc/compare/master...remotivelabs:elixir-grpc:cancel-failing?expand=1

And the passing (unmodified) test with Client side streaming

grpc/interop/lib/interop/client.ex

Lines 253 to 259 in d5ad40a

	def cancel_after_begin!(ch) do
	Logger.info("Run cancel_after_begin!")
	stream = Grpc.Testing.TestService.Stub.streaming_input_call(ch)
	stream = GRPC.Stub.cancel(stream)
	error = GRPC.RPCError.exception(1, "The operation was cancelled")
	{:error, ^error} = GRPC.Stub.recv(stream)
	end

Initial finding

This is a GRCP.Stub client side issue (or possibly miss use from my side). Cancelling the same stream from a python client does work.