io.helidon.webserver.HttpPipelineTest hangs periodically

Periodically the io.helidon.webserver.HttpPipelineTest test case hangs seemingly indefinitely. I wanted to capture this issue here. There is no output.

[barchetta]

The above PRs seem to fix the issue (fingers crossed). Closing.

[barchetta]

I’m seeing this more often in helidon-2.x when upgrading netty to 4.1.76.Final in my local repo. The test fails with java.net.SocketTimeoutException:

java.net.SocketTimeoutException: Read timed out
	at java.base/java.net.SocketInputStream.socketRead0(Native Method)
	at java.base/java.net.SocketInputStream.socketRead(SocketInputStream.java:115)
	at java.base/java.net.SocketInputStream.read(SocketInputStream.java:168)
	at java.base/java.net.SocketInputStream.read(SocketInputStream.java:140)
	at java.base/sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:284)
	at java.base/sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:326)
	at java.base/sun.nio.cs.StreamDecoder.read(StreamDecoder.java:178)
	at java.base/java.io.InputStreamReader.read(InputStreamReader.java:181)
	at java.base/java.io.BufferedReader.fill(BufferedReader.java:161)
	at java.base/java.io.BufferedReader.readLine(BufferedReader.java:326)
	at java.base/java.io.BufferedReader.readLine(BufferedReader.java:392)
	at io.helidon.webserver.utils.SocketHttpClient.receive(SocketHttpClient.java:266)
	at io.helidon.webserver.HttpPipelineTest.testPipelining(HttpPipelineTest.java:116)

I did not see this in helidon 3 (master). Here is the test output (I added the request number to one of the log output – that’s why it might look slightly different than what is in the helidon-2.x branch):

2022.04.13 11:16:26 INFO io.helidon.webserver.NettyWebServer Thread[nioEventLoopGroup-62-1,10,main]: Channel '@default' started: [id: 0xed5f5988, L:/127.0.0.1:61259]
2022.04.13 11:16:26 INFO io.helidon.webserver.HttpPipelineTest Thread[main,5,main]: Started server at: https://localhost:61259
2022.04.13 11:16:26 INFO io.helidon.webserver.HttpPipelineTest Thread[main,5,main]: put client Thread[main,5,main]
2022.04.13 11:16:27 INFO io.helidon.webserver.HttpPipelineTest Thread[nioEventLoopGroup-63-1,10,main]: put server Thread[nioEventLoopGroup-63-1,10,main]
2022.04.13 11:16:27 INFO io.helidon.webserver.HttpPipelineTest Thread[nioEventLoopGroup-63-1,10,main]: put: / Thread[nioEventLoopGroup-63-1,10,main]
2022.04.13 11:16:27 INFO io.helidon.webserver.HttpPipelineTest Thread[main,5,main]: request0 client Thread[main,5,main]
2022.04.13 11:16:27 INFO io.helidon.webserver.HttpPipelineTest Thread[nioEventLoopGroup-63-1,10,main]: get server 0 Thread[nioEventLoopGroup-63-1,10,main]
2022.04.13 11:16:27 INFO io.helidon.webserver.HttpPipelineTest Thread[nioEventLoopGroup-63-1,10,main]: get server 1 Thread[nioEventLoopGroup-63-1,10,main]
2022.04.13 11:16:27 INFO io.helidon.webserver.HttpPipelineTest Thread[pool-305-thread-1,5,main]: get server schedule 1 Thread[pool-305-thread-1,5,main]
2022.04.13 11:16:28 INFO io.helidon.webserver.HttpPipelineTest Thread[pool-305-thread-1,5,main]: get server schedule 0 Thread[pool-305-thread-1,5,main]
2022.04.13 11:16:28 INFO io.helidon.webserver.HttpPipelineTest Thread[main,5,main]: request1 client Thread[main,5,main]
2022.04.13 11:16:38 INFO io.helidon.webserver.NettyWebServer Thread[nioEventLoopGroup-62-1,10,main]: Channel '@default' closed: [id: 0xed5f5988, L:/127.0.0.1:61259]

I think this output looks OK. We do a PUT and two GETs. The server sends the GET responses out of order (that’s what we are testing). The client reads the first GET response and it’s correct (0), but it blocks when it reads the second response.