I agree, this is concerning. There is a similar situation with JCL in SOLR 1.4 (http://www.mail-archive.com/solr-dev@lucene.apache.org/msg13600.html). With log4j-over-slf4j-X.Y.Z.jar in the .war file, whoever will need to switch the logging system will have to make sure that an appropriate set of *-over-slf4j and slf4j-* files is in the classpath.
So, it might make sense to change the last paragraph of http://wiki.apache.org/solr/SolrLogging to something like this: ---- Users who want an alternate logging implementation (log4j, logback, jcl, etc) will need to repackage the .war file and replace slf4j-jdk14-X.Y.Z.jar with an alternate implementation. They should also remove jcl-over-slf4j-X.Y.Z.jar if they are switching to JCL and log4j-over-slf4j-X.Y.Z.jar if they are using cloud branch and switching to log4j. Having both jcl-over-slf4j and slf4j-jcl.jar or log4j-over-slf4j.jar and slf4j-log4j.jar in the classpath may result in an infinite loop. ---- There is already a link to slf4j site on the page. But, it might be also useful to add a link directly to the page that describes SLF4J bridges: http://www.slf4j.org/legacy.html Igor On Thu, Mar 25, 2010 at 4:26 PM, Mark Miller <markrmil...@gmail.com> wrote: > On 03/25/2010 11:27 AM, Mark Miller wrote: > >> On 03/25/2010 11:22 AM, Igor Motov wrote: >> >>> I wonder if it would make sense to replace log4j-1.2.15.jar in the lib >>> directory of the cloud branch with log4j-over-slf4j-1.5.5.jar. SOLR is >>> already using SLF4J for its logging and log4j-over-slf4j bridge would >>> redirect all ZooKeeper log messages into the same SLF4J logging stream. I >>> did it in my setup and and it helped me a lot when I ran into issues with >>> my >>> ZooKeeper configuration. >>> >>> Thank you, >>> >>> Igor >>> >>> Yeah, this is a great idea - been meaning to look into this since Uwe >> mentioned to me that it was possible the other week. Hadn't realized these >> bridge jars existed previously. Yonik had started looking into getting the >> ZooKeeper project to switch to SLF4J, but this is a great solution for now. >> >> > Hmm - I've done this for now - but this is going to need some good > documentation at the least. It works great for Solr in it's default state > (using util logging) - but you don't want this jar if you choose to use the > log4j connector. Otherwise they loop back and forth with each other. > > -- > - Mark > > http://www.lucidimagination.com > > > >
