[grpc-java] client-side reconnect

[Ivan Vaskevych]

Hi,

How do I use client-side backoff reconnect correctly?

Scenario: client-side streaming, plainText. When I stop the server I get the error below.

After server restart, client doesn't reconnect. That makes sense since I get onError on my StreamObserver.

What should I do on client side, recreate a channel?

client-side error logged from onError:

io.grpc.StatusRuntimeException: INTERNAL: Connection closed with unknown cause

        at io.grpc.Status.asRuntimeException(Status.java:545)

        at io.grpc.stub.ClientCalls$StreamObserverToCallListenerAdapter.onClose(ClientCalls.java:395)

        at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl.close(ClientCallImpl.java:481)

        at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl.access$600(ClientCallImpl.java:398)

        at io.grpc.internal.ClientCallImpl$ClientStreamListenerImpl$1StreamClosed.runInContext(ClientCallImpl.java:513)

        at io.grpc.internal.ContextRunnable.run(ContextRunnable.java:52)

        at io.grpc.internal.SerializingExecutor$TaskRunner.run(SerializingExecutor.java:154)

        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)

        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)

        at java.lang.Thread.run(Thread.java:745)

Thanks!

[Louis Ryan]

Inf-flight streams do not survive server disconnects. The Channel you created on the client will attempt to reconnect so can so you can re-start your call

--
You received this message because you are subscribed to the Google Groups "grpc.io" group.
To unsubscribe from this group and stop receiving emails from it, send an email to grpc-io+unsubscribe@googlegroups.com.
To post to this group, send email to grp...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/grpc-io/24389235-a9ff-47c4-8987-f1d205d09364%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Ivan Vaskevych]

Yes, I can reuse the Channel. But I do so from the onError of my StreamObserver and it creates a new instance of self (StreamObserver). That also creates excessive logging due to constant (onError -> try to connect) cycles.

Is there a better way to do it?

Thanks!

--

Best Regards,
 Ivan

[Louis Ryan]

You probably want to use CallOptions.withWaitForReady() so that the call queues until the transport becomes available.

[Eric Anderson]

Note that we are aware setting wait for ready is more painful than it should be (you have to use a client interceptor today), due to these two issues.

To view this discussion on the web visit https://groups.google.com/d/msgid/grpc-io/CADQ0XY02%3DcWd5t6mGdJ8L%3D6S%3Dam3FWwexhc5dHGESsmieiz-mA%40mail.gmail.com.