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https://issues.apache.org/jira/browse/LOG4J2-3585?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17600585#comment-17600585
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ASF subversion and git services commented on LOG4J2-3585:
---------------------------------------------------------
Commit 674dae6d5596ce33473d8f4588128c155ba5d23c in logging-log4j2's branch
refs/heads/dependabot/maven/spring-boot.version-2.7.3 from Piotr P. Karwasz
[ https://gitbox.apache.org/repos/asf?p=logging-log4j2.git;h=674dae6d55 ]
[LOG4J2-3585] Fix throwable logging
An inverted condition prevented throwables to be added as additional
arguments.
> Exception in Parameterized Message not logged using LocationAwareLogger API
> ---------------------------------------------------------------------------
>
> Key: LOG4J2-3585
> URL: https://issues.apache.org/jira/browse/LOG4J2-3585
> Project: Log4j 2
> Issue Type: Bug
> Components: SLF4J Bridge
> Affects Versions: 2.17.1
> Environment: Windows 10, Tomcat 9, Java 8
> Reporter: Marian Barton
> Assignee: Piotr Karwasz
> Priority: Major
>
> +Versions:+
> * slf4j-api version 1.7.36
> * log4j-core/log4j-slf4j-impl: 2.17.1
> +Action:+
> Logging a message using LocationAwareLogger.log including an exception as
> unused last parameter in the params array.
> +Result:+
> The message is constructed correctly but the exception is being ignored and
> not logged.
> +Expected:+
> According to the SLF4J FAQ, passing an exception as unused parameter in the
> last place should result in it being interpreted as Exception and logged as
> such.
> +Example:+
> {code:java}
> // Method in wrapping custom logger
> public void error(final String message, final Object... argArray) {
> logger.log(null, FQCN, LocationAwareLogger.ERROR_INT, message, argArray,
> null);
> }
> // Call from another class to that method
> String someString = "insertedString";
> LOGGER.log("Test {}", someString, someException);
> // Result - no exception logged, only message
> 2022-Aug.-31 12:41:59,829 [https-openssl-nio-443-exec-4] some.Class
> ERROR Test insertedString
> // this works though
> public void error(final String message, final Object... argArray) {
> logger.error(message, argArray);
> }{code}
> The same call works when not using the LocationAwareLogger log method but the
> standard logger.error(String message, Object... argArray) method. But since I
> am using a wrapping logger I have to use the LocationAwareLogger interface in
> order to conserve the location information.
> +Possible solution:+
> I debugged a bit to try and find the issue and I might have found the problem
> inside the org.apache.logging.slf4j.Log4jLogger.log method:
> {code:java}
> @Override
> public void log(final Marker marker, final String fqcn, final int level,
> final String message, final Object[] params, Throwable throwable) {
> final Level log4jLevel = getLevel(level);
> final org.apache.logging.log4j.Marker log4jMarker = getMarker(marker);
> if (!logger.isEnabled(log4jLevel, log4jMarker, message, params)) {
> return;
> }
> final Message msg;
> if (CONVERTER != null && eventLogger && marker != null &&
> marker.contains(EVENT_MARKER)) {
> msg = CONVERTER.convertEvent(message, params, throwable);
> } else if (params == null) {
> msg = new SimpleMessage(message);
> } else {
> msg = new ParameterizedMessage(message, params, throwable);
> if (throwable != null) {
> throwable = msg.getThrowable();
> }
> }
> logger.logMessage(fqcn, log4jLevel, log4jMarker, msg, throwable);
> }
> {code}
> The problem here specifically being this part:
> {code:java}
> } else {
> msg = new ParameterizedMessage(message, params, throwable);
> if (throwable != null) {
> throwable = msg.getThrowable();
> }
> }
> {code}
> Log4J successfully detects this as and creates a ParameterizedMessage. This
> instance also correctly found the Throwable from the parameters and set it to
> its throwable property.
> Now I think the bug here is that the if condition is inverted. As I have no
> Throwable explicitly passed to this method (because it is passed via the
> params), it is currently null. In this case SLF4J should check if a Throwable
> is set and if not try to get it from the ParameterizedMessage, because there
> it was successfully detected inside the constructor.
> The correct implementation would therefore be:
> {code:java}
> } else {
> msg = new ParameterizedMessage(message, params, throwable);
> if (throwable == null) {
> throwable = msg.getThrowable();
> }
> }
> {code}
> If the throwable is not set here, it remains inside the ParameterizedMessage
> and is ignored by Log4J, as Log4J appears to only respect the explicit
> Throwable parameter.
> Any questions, feedback and help are/is appreciated.
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