CC'd the +1ers of KIP-653 with detailed context: When I submitted and got the approval of KIP-653: Upgrade log4j to log4j2 <https://cwiki.apache.org/confluence/display/KAFKA/KIP-653%3A+Upgrade+log4j+to+log4j2>, I thought the log4j2-appender should not be the scope of the work. But it was wrong.
Since the VerifiableLog4jAppender tool is built upon log4j-appender, log4j 1.x artifact will co-exist with log4j2 artifact in the classpath within this scheme. Since the log4j 1.x code is not called anymore, I thought it is not problematic but actually, it was not - when I started to provide a preview of KIP-653 <http://home.apache.org/~dongjin/post/apache-kafka-log4j2-support/>, some users reported that sometimes slf4j fails to find the appropriate binding within the classpath, resulting fail to append the log message. To resolve this problem, I subtly adjusted the scope of the work; I excluded Tools and Trogdor from KIP-653 and extended KIP-719 to take care of them instead, along with providing log4j2-appender. It is why the current WIP implementations include some classpath logic in the shell script and *why KIP-653 only can't complete the log4j2 migration*. I hope you will check this proposal out. Best, Dongjin On Tue, May 25, 2021 at 10:43 PM Dongjin Lee <dong...@apache.org> wrote: > Bumping up the discussion thread. > > Recently, I updated the document of KIP-653: Upgrade log4j to log4j2 > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-653%3A+Upgrade+log4j+to+log4j2> > (accepted) > and KIP-719: Add Log4J2 Appender > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-719%3A+Add+Log4J2+Appender> > (under > discussion) reflecting the recent changes to our codebase. Especially: > > 1. KIP-653 document > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-653%3A+Upgrade+log4j+to+log4j2> > now > explains which modules will be migrated and why. > 2. KIP-719 document > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-719%3A+Add+Log4J2+Appender> > now > explains not only the log4j2-appender plan but also upgrading the omitted > modules in KIP-653 into log4j2. > > As you can see here, those two KIPs are the different parts of the same > problem. I believe the community will have a good grasp on why both KIPs > are best if released altogether. > > I will open the voting thread now, and please leave a vote if you are > interested in this issue. > > Best, > Dongjin > > On Tue, Mar 2, 2021 at 5:00 PM Dongjin Lee <dong...@apache.org> wrote: > >> Hi Kafka dev, >> >> I would like to start the discussion of KIP-719: Add Log4J2 Appender. >> >> >> https://cwiki.apache.org/confluence/display/KAFKA/KIP-719%3A+Add+Log4J2+Appender >> >> All kinds of feedbacks are greatly appreciated! >> >> Best, >> Dongjin >> >> -- >> *Dongjin Lee* >> >> *A hitchhiker in the mathematical world.* >> >> >> >> *github: <http://goog_969573159/>github.com/dongjinleekr >> <https://github.com/dongjinleekr>keybase: https://keybase.io/dongjinleekr >> <https://keybase.io/dongjinleekr>linkedin: kr.linkedin.com/in/dongjinleekr >> <https://kr.linkedin.com/in/dongjinleekr>speakerdeck: speakerdeck.com/dongjin >> <https://speakerdeck.com/dongjin>* >> > > > -- > *Dongjin Lee* > > *A hitchhiker in the mathematical world.* > > > > *github: <http://goog_969573159/>github.com/dongjinleekr > <https://github.com/dongjinleekr>keybase: https://keybase.io/dongjinleekr > <https://keybase.io/dongjinleekr>linkedin: kr.linkedin.com/in/dongjinleekr > <https://kr.linkedin.com/in/dongjinleekr>speakerdeck: speakerdeck.com/dongjin > <https://speakerdeck.com/dongjin>* > -- *Dongjin Lee* *A hitchhiker in the mathematical world.* *github: <http://goog_969573159/>github.com/dongjinleekr <https://github.com/dongjinleekr>keybase: https://keybase.io/dongjinleekr <https://keybase.io/dongjinleekr>linkedin: kr.linkedin.com/in/dongjinleekr <https://kr.linkedin.com/in/dongjinleekr>speakerdeck: speakerdeck.com/dongjin <https://speakerdeck.com/dongjin>*