Armeria: Status.UNKNOWN in attempt to connect to a closed port

[andrey-tpt]

Hi guys,

Found a small discrepancy (unless I'm doing something wrong), when I tested Armeria gRPC client (0.88). StatusRuntimeException/UNAVAILABLE is returned if I send a request to a closed port via pure gRPC client (1.21), however Armeria client in this case returns StatusRuntimeException/UNKNOWN.

This looks misleading - the service is clearly unavailable on the closed port.

Sincerely,
Andrey

[ikhoon]

Hi @andrey-tpt, Thanks for reporting this issue.
First I've checked the status decision logic, but there is no difference. See HTTP to gRPC Status Code Mapping
for more information.

• Armeria
  https://github.com/line/armeria/blob/85e7e386b7222655d9ae3cf577f0f5f77c5cae85/grpc/src/main/java/com/linecorp/armeria/internal/grpc/GrpcStatus.java#L184-L190
• gRPC-Java
  https://github.com/grpc/grpc-java/blob/5c239437a2cd16487bc0beead6384cab1e8e8a77/core/src/main/java/io/grpc/internal/GrpcUtil.java#L289-L295

Let me reproduce this and investigate it more.
@anuraaga Do you have any guesses?

[ikhoon]

when I tested Armeria gRPC client (0.88).

@andrey-tpt Could you test it with the latest version(0.97.0) of Armeria gRPC client for clarity?

[anuraaga]

This is for when the port is closed - so there's no http status to map. In fromThrowable above we need to map the exception we see for when unable to connect at all. I think I might have found that hard and left a comment like that ;)

[ikhoon]

I got UNAVAILABLE status when a request is sent to an unavailable destination.

io.grpc.StatusRuntimeException: UNAVAILABLE
    at io.grpc.Status.asRuntimeException(Status.java:533)
    at io.grpc.stub.ClientCalls$StreamObserverToCallListenerAdapter.onClose(ClientCalls.java:447)
    at com.linecorp.armeria.client.grpc.ArmeriaClientCall.close(ArmeriaClientCall.java:410)
    at com.linecorp.armeria.client.grpc.ArmeriaClientCall.transportReportStatus(ArmeriaClientCall.java:369)
    at com.linecorp.armeria.internal.grpc.TransportStatusListener.transportReportStatus(TransportStatusListener.java:28)
    at com.linecorp.armeria.internal.grpc.HttpStreamReader.apply(HttpStreamReader.java:185)
    at com.linecorp.armeria.internal.grpc.HttpStreamReader.apply(HttpStreamReader.java:48)
    at java.base/java.util.concurrent.CompletableFuture.uniHandle(CompletableFuture.java:930)
    at java.base/java.util.concurrent.CompletableFuture$UniHandle.tryFire(CompletableFuture.java:907)
    at java.base/java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:478)
    at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163)
    at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:510)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:518)
    at io.netty.util.concurrent.SingleThreadEventExecutor$6.run(SingleThreadEventExecutor.java:1050)
    at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
    at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
    at java.base/java.lang.Thread.run(Thread.java:835)
Caused by: com.linecorp.armeria.client.UnprocessedRequestException: io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: 127.0.0.1/127.0.0.1:8080
    at com.linecorp.armeria.client.HttpChannelPool.notifyConnect(HttpChannelPool.java:458)
    at com.linecorp.armeria.client.HttpChannelPool.lambda$connect$5(HttpChannelPool.java:331)
    at io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:577)
    at io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:551)
    at io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:490)
    at io.netty.util.concurrent.DefaultPromise.setValue0(DefaultPromise.java:615)
    at io.netty.util.concurrent.DefaultPromise.setFailure0(DefaultPromise.java:608)
    at io.netty.util.concurrent.DefaultPromise.setFailure(DefaultPromise.java:109)
    at com.linecorp.armeria.client.HttpChannelPool.lambda$connect$6(HttpChannelPool.java:353)
    at io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:577)
    at io.netty.util.concurrent.DefaultPromise.notifyListeners0(DefaultPromise.java:570)
    at io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:549)
    at io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:490)
    at io.netty.util.concurrent.DefaultPromise.setValue0(DefaultPromise.java:615)
    at io.netty.util.concurrent.DefaultPromise.setFailure0(DefaultPromise.java:608)
    at io.netty.util.concurrent.DefaultPromise.tryFailure(DefaultPromise.java:117)
    at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.fulfillConnectPromise(AbstractNioChannel.java:321)
    at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.finishConnect(AbstractNioChannel.java:337)
    at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:688)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:635)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:552)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:514)
    ... 4 more
Caused by: io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: 127.0.0.1/127.0.0.1:8080
Caused by: java.net.ConnectException: Connection refused

@andrey-tpt Could you put your full stacktrace log about StatusRuntimeException/UNKNOWN?

[ikhoon]

In fromThrowable above we need to map the exception we see for when unable to connect at all.

I think the following code covers the connection fail since the exception is wrapped with UnprocessRequestException. #1848
https://github.com/line/armeria/blob/85e7e386b7222655d9ae3cf577f0f5f77c5cae85/grpc/src/main/java/com/linecorp/armeria/internal/grpc/GrpcStatus.java#L103-L105

[andrey-tpt]

when I tested Armeria gRPC client (0.88).

@andrey-tpt Could you test it with the latest version(0.97.0) of Armeria gRPC client for clarity?

Thank you, guys. I can confirm that in my case with Armeria 0.97 expected status UNVAILABLE is returned from connection to a closed port. Now I need somehow to migrate from gRPC 1.21 to 1.25.