HOTFIX: ClassCastException in request logging

[hachikuji]

No description provided.

[hachikuji]

cc @cmccabe @ewencp @ijuma

When TRACE logging is enabled, we see this:

[2017-02-17 23:09:49,444] ERROR Processor got uncaught exception. (kafka.network.Processor)
java.lang.ClassCastException: Expected request with type class scala.runtime.Nothing$, but found class org.apache.kafka.common.requests.ApiVersionsRequest
    at kafka.network.RequestChannel$Request.body(RequestChannel.scala:118)
    at kafka.network.RequestChannel$Request.requestDesc(RequestChannel.scala:111)
    at kafka.network.RequestChannel$Request.updateRequestMetrics(RequestChannel.scala:169)
    at kafka.network.Processor$$anonfun$processCompletedSends$1.apply(SocketServer.scala:532)
    at kafka.network.Processor$$anonfun$processCompletedSends$1.apply(SocketServer.scala:528)
    at scala.collection.Iterator$class.foreach(Iterator.scala:893)
    at scala.collection.AbstractIterator.foreach(Iterator.scala:1336)
    at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
    at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
    at kafka.network.Processor.processCompletedSends(SocketServer.scala:528)
    at kafka.network.Processor.run(SocketServer.scala:434)
    at java.lang.Thread.run(Thread.java:745)

[cmccabe]

LGTM (non-binding)

[ewencp]

LGTM, and I assume tests will pass since this wasn't being exercised. Not sure if it's worth adding a test specifically for this, though it seems like we might want to also turn on trace logging during tests or something like that since that's the only way to exercise all code paths like this.

[hachikuji]

@ewencp Yeah, agreed. I'll add a JIRA to do that since I'm pretty sure this is not the first time we've had a bug which only affected logging.

[asfbot]

Refer to this link for build results (access rights to CI server needed):
https://builds.apache.org/job/kafka-pr-jdk7-scala2.10/1746/
Test PASSed (JDK 7 and Scala 2.10).

[asfbot]

Refer to this link for build results (access rights to CI server needed):
https://builds.apache.org/job/kafka-pr-jdk8-scala2.12/1746/
Test PASSed (JDK 8 and Scala 2.12).

[asfbot]

Refer to this link for build results (access rights to CI server needed):
https://builds.apache.org/job/kafka-pr-jdk8-scala2.11/1749/
Test PASSed (JDK 8 and Scala 2.11).

[ijuma]

@hachikuji, thanks for fixing this. I filed a JIRA for the logging thing a while back due to a similar incident.

[hachikuji]

@ijuma No worries. I probably should have tried at least one of the sanity system tests prior to merging.