Setting a deadline for a request

[michaeldelago]

Something that seems to be missing is setting a deadline for a request. I can see that setting an infinite deadline is hardcoded into client.cc, but to my (limited) understanding, other grpc implementations (namely Go) take an infinite deadline to mean there isn't a deadline.

Is there a clean way that we can integrate deadlines into this implementation?

in the examples at grpc/grpc, python uses syntax like this (source):

try:
    response = stub.SayHello(
        helloworld_pb2.HelloRequest(name=message), timeout=3
    )
    print(f"Greeter client received: {response.message}")
except grpc.RpcError as rpc_error:
    print(f"Call failed with code: {rpc_error.code()}")

Noting that the syntax for python appears to be emitted from the python protobuf compiler, but that doesn't happen from cl-protobufs.

For CL, I suppose an equivalent would look like this

(handler-case
  (testing-rpc:call-say-hello channel (testing:make-hello-request :name message) :deadline 3)
 (grpc:grpc-call-error (c)
    (format t "call failed due to ~a" c)))

An alternative (and admittedly the first one I thought of) syntax for CL could use lexical variables:

(let ((grpc:*call-deadline* 3))
  (handler-case
    (testing-rpc:call-say-hello channel (testing:make-hello-request :name message))
   (grpc:grpc-call-error (c)
     (format t "call failed due to ~a" c))))

Thoughts? Am I missing on how to use deadlines in this library? If not, how can we implement it?