Setting a deadline for a long-lived streaming stub

[danotorrey]

We are using an implementation of bi-directional gRPC streaming, and are interested in setting an appropriate deadline for each request. The stub is used for a long-lived/high throughput stream.

When using unary, I know we could create a new stub for each request, then use it for the unary request.

However, with streaming, the stub is used for lots and lots of requests. Is there a way to set the deadline for an existing stub on on a message by message basis? I did not see anything for streaming deadlines in the examples https://github.com/grpc/grpc-java/tree/master/examples.

In our code, we are using requestStreamObserver.onNext(requestMessage) to queue up each message for sending.

What version of gRPC are you using? 1.19.0

[danotorrey]

Is this the correct way to go? Is there any known performance impact from setting a deadline like this for our high throughput scenario?

this.stub = stub.withDeadlineAfter(10000L, TimeUnit.MILLISECONDS);
requestStreamObserver.onNext(requestMessage);

[carl-mastrangelo]

Hi,

Deadlines aren't used often on streaming calls. You can set a deadline per message, but it's a little more difficult to do. You will need to fork the stub with a ClientInterceptor, which sets a timer for each message, and cancels it each time a message is received. I made a similar example for doing connection timeouts, but you can use it as a starting point:

carl-mastrangelo@4a31a58

You will need to override the onMessage method of the listener.

[danotorrey]

Thank you @carl-mastrangelo! This is exactly what we needed.

[danotorrey]

Thank you for the example @carl-mastrangelo. This worked perfectly for our implementation.