Hi Viktor, A logging library that requires Java 17 is a deal breaker since we need to log from modules that will only require Java 11 in Apache Kafka 4.0.
Ismael On Wed, Jan 10, 2024 at 6:43 PM Viktor Somogyi-Vass <viktor.somo...@cloudera.com.invalid> wrote: > Hi Mickael, > > Reacting to your points: > 1. I think it's somewhat unfortunate that we provide an appender tied to a > chosen logger implementation. I think that this shouldn't be part of the > project in its current form. However, there is the sl4fj2 Fluent API which > may solve our problem and turn KafkaLog4jAppender into a generic > implementation that doesn't depend on a specific library given that we can > upgrade to slf4j2. That is worth considering. > 2. Since KIP-1013 we'd move to Java17 anyways by 4.0, so I don't feel it's > a problem if there's a specific dependency that has Java17 as the minimum > supported version. As I read though from your email thread with the log4j2 > folks, it'll be supported for years to come and log4j3 isn't yet stable. > Since we already use log4j2 in our fork, I'm happy to contribute to this, > review PRs or drive it if needed. > > Thanks, > Viktor > > On Wed, Jan 10, 2024 at 3:58 PM Mickael Maison <mickael.mai...@gmail.com> > wrote: > > > I asked for details about the future of log4j2 on the logging user list: > > https://lists.apache.org/thread/6n6bkgwj8tglgdgzz8wxhkx1p1xpwodl > > > > Let's see what they say. > > > > Thanks, > > Mickael > > > > On Wed, Jan 10, 2024 at 3:23 PM Ismael Juma <m...@ismaeljuma.com> wrote: > > > > > > Hi Mickael, > > > > > > Thanks for starting the discussion and for summarizing the state of > > play. I > > > agree with you that it would be important to understand how long log4j2 > > > will be supported for. An alternative would be sl4fj 2.x and logback. > > > > > > Ismael > > > > > > On Wed, Jan 10, 2024 at 2:17 PM Mickael Maison < > mickael.mai...@gmail.com > > > > > > wrote: > > > > > > > Hi, > > > > > > > > Starting a new thread to discuss the current logging situation in > > > > Kafka. I'll restate everything we know but see the [DISCUSS] Road to > > > > Kafka 4.0 if you are interested in what has already been said. [0] > > > > > > > > Currently Kafka uses SLF4J and reload4j as the logging backend. We > had > > > > to adopt reload4j in 3.2.0 as log4j was end of life and has a few > > > > security issues. > > > > > > > > In 2020 we adopted KIP-653 to upgrade to log4j2. Due to > > > > incompatibilities in the configuration mechanism with log4j/reload4j > > > > we decide to delay the upgrade to the next major release, Kafka 4.0. > > > > > > > > Kafka also currently provides a log4j appender. In 2022, we adopted > > > > KIP-719 to deprecate it since we wanted to switch to log4j2. At the > > > > time Apache Logging also had a Kafka appender that worked with > log4j2. > > > > They since deprecated that appender in log4j2 and it is not part of > > > > log4j3. [1] > > > > > > > > Log4j3 is also nearing release but it seems it will require Java 17. > > > > The website states Java 11 [2] but the artifacts from the latest > 3.0.0 > > > > beta are built for Java 17. I was not able to find clear maintenance > > > > statement about log4j2 once log4j3 gets released. > > > > > > > > The question is where do we go from here? > > > > We can stick with our plans: > > > > 1. Deprecate the appender in the next 3.x release and plan to remove > > it in > > > > 4.0 > > > > 2. Do the necessary work to switch to log4j2 in 4.0 > > > > If so we need people to drive these work items. We have PRs for these > > > > with hopefully the bulk of the code but they need > > > > rebasing/completing/reviewing. > > > > > > > > Otherwise we can reconsider KIP-653 and/or KIP-719. > > > > > > > > Assuming log4j2 does not go end of life in the near future (We can > > > > reach out to Apache Logging to clarify that point.), I think it still > > > > makes sense to adopt it. I would also go ahead and deprecate our > > > > appender. > > > > > > > > Thanks, > > > > Mickael > > > > > > > > 0: https://lists.apache.org/thread/q0sz910o1y9mhq159oy16w31d6dzh79f > > > > 1: https://github.com/apache/logging-log4j2/issues/1951 > > > > 2: https://logging.apache.org/log4j/3.x/#requirements > > > > > > >
