NamedLogHandlersBuildItem causes stderr "Handler is linked to a category but not configured"

[rquinio1A]

Describe the bug

We've added support for named log handlers in quarkus-logging-splunk extension, thanks to Quarkus NamedLogHandlersBuildItem that was introduced in #7568

Our config looks like:

quarkus.log.handler.splunk."MONITORING".key=value
quarkus.log.category."monitoring".handlers=MONITORING

The extension builds one handler for every nested quarkus.log.handler.splunk."named-handler" config entries, and registers them at runtime init via NamedLogHandlersBuildItem.

Even though the log category and handler work properly, there's an stderr log at Quarkus startup:
LogManager error of type GENERIC_FAILURE: Handler with name 'MONITORING' is linked to a category but not configured.

Expected behavior

No response

Actual behavior

No response

How to Reproduce?

Run https://github.com/quarkiverse/quarkus-logging-splunk/blob/main/deployment/src/test/java/io/quarkiverse/logging/splunk/LoggingSplunkNamedHandlerConfigTest.java
In the console stderr:
LogManager error of type GENERIC_FAILURE: Handler with name 'MONITORING' is linked to a category but not configured.

Output of uname -a or ver

No response

Output of java -version

No response

Quarkus version or git rev

3.15.2

Build tool (ie. output of mvnw --version or gradlew --version)

No response

Additional information

Intially reported in quarkiverse/quarkus-logging-splunk#319
This is reproducible with Quarkus 3.2, 3.8 and 3.15
The core handlers (console, file, ...) don't rely on NamedLogHandlersBuildItem , so I suspect the issue has always been present because it's not directly used in Quarkus itself.
Maybe the check on quarkus.log.category.handlers happens before NamedLogHandlersBuildItem are consumed ?

[quarkus-bot]

/cc @radcortez (config)

[geoand]

Maybe the check on quarkus.log.category.handlers happens before NamedLogHandlersBuildItem are consumed ?

I think it makes sense. Would you like to contribute that?

[rquinio1A]

@geoand I've done some debugging and the setup of categories is done twice:

• Once in #initializeBuildTimeLogging with only the core named handlers

  quarkus/core/runtime/src/main/java/io/quarkus/runtime/logging/LoggingSetupRecorder.java

  Line 347 in 0a44026

  setUpCategoryLoggers(buildConfig, categoryDefaultMinLevels, categories, logContext, errorManager, namedHandlers);

• Another time in #initializeLogging, this time with the core named handlers + the ones from NamedLogHandlersBuildItem

  quarkus/core/runtime/src/main/java/io/quarkus/runtime/logging/LoggingSetupRecorder.java

  Line 264 in 0a44026

  setUpCategoryLoggers(buildConfig, categoryDefaultMinLevels, categories, logContext, errorManager, namedHandlers);

So a naive fix would be to remove the first call.

[gsmet]

We need to set up the categories for build time, but we probably need to ignore the config for the named handlers.

[geoand]

Makes sense