[JAMES-3862] Log4J/SLF4J Binding is broken in james-server-spring-app

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.8.0
• Fix Version/s: 3.7.3
• Assignee: Unassigned
• Reporter: Bernd Bartke
• Created: 24/Nov/22 08:27
• Updated: 08/Dec/22 01:51
• Resolved: 08/Dec/22 01:51

Description

Log4J/SLF4J Binding is broken in james-server-spring-app, starting with 3.7.2.

Server startup of 3.7.2:

C:\bin\james-server-spring-app-3.7.2\bin>run.bat
SLF4J: No SLF4J providers were found.
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See https://www.slf4j.org/codes.html#noProviders for further details.
SLF4J: Class path contains SLF4J bindings targeting slf4j-api versions 1.7.x or earlier.
SLF4J: Ignoring binding found at [jar:file:/C:/bin/james-server-spring-app-3.7.2/lib/log4j-slf4j-impl-2.17.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See https://www.slf4j.org/codes.html#ignoredBindings for an explanation.
15  James  WARN   [main] openjpa.Runtime - An error occurred while registering a ClassTransformer with PersistenceUnitInfo: name 'James', root URL [file:/C:/bin/james-server-spring-app-3.7.2/conf]. The error has been consumed. To see it, set your openjpa.Runtime log level to TRACE. Load-time class transformation will not be available.
9281  James  INFO   [main] openjpa.Runtime - Starting OpenJPA 3.2.0

Issue was introduced with commit 3460270c3a928da6ee650194a9d4f1a08e53947e by TRAN at 2022-09-20:
slf4j.version has been changed from 1.7.36 to 2.0.1

SLF4J 2 requires updated SLF4J to Log4j Adapters:

SLF4J 2 ServiceLoader mechanism to find its logging backend
https://www.slf4j.org/faq.html#changesInVersion200

https://logging.apache.org/log4j/2.x/log4j-slf4j-impl/

Due to a break in compatibility in the SLF4J binding, as of release 2.19.0 two SLF4J to Log4j Adapters are provided.
...
2. log4j-slf4j2-impl should be used with SLF4J 2.0.x releases or newer.

To fix the issue, the 3 pom.xml referencing artifactId log4j-slf4j-impl should reference artifactId log4j-slf4j2-impl instead (- log4j2.version is already set to 2.19.0, ):

$ grep -r --include="pom.xml" "log4j-slf4j-impl" *
pom.xml:                <artifactId>log4j-slf4j-impl</artifactId>
server/apps/spring-app/pom.xml:            <artifactId>log4j-slf4j-impl</artifactId>
server/container/spring/pom.xml:            <artifactId>log4j-slf4j-impl</artifactId>

Issue Links

• links to: GitHub Pull Request #1333
• links to: GitHub Pull Request #1335