ScriptPatternSelector properties example throws "No type attribute provided for component patternMatch"

[martin-dorey-hv]

Problem is at https://github.com/apache/logging-log4j2/blame/f7c26cd7710fdace463a370e85d0971107c91d8b/src/site/antora/modules/ROOT/examples/manual/pattern-layout/script-pattern-selector/log4j2.properties#L33

I suggest:

martind@stormy:~/tmp/D161042$ diff -u log4j2.properties{.orig,}
--- log4j2.properties.orig	2024-10-10 15:31:13.405464567 -0700
+++ log4j2.properties	2024-10-10 15:31:34.670434140 -0700
@@ -30,12 +30,12 @@
 } else {\
   return null;\
 }
-appender.0.layout.patternSelector.patternMatch.0.type = PatternMatch
-appender.0.layout.patternSelector.patternMatch.0.key = NoLocation
-appender.0.layout.patternSelector.patternMatch.0.pattern = [%-5level] %c{1.} %msg%n
-appender.0.layout.patternSelector.patternMatch.1.type = PatternMatch
-appender.0.layout.patternSelector.patternMatch.1.key = Flow
-appender.0.layout.patternSelector.patternMatch.1.pattern = [%-5level] %c{1.} ====== %C{1.}.%M:%L %msg ======%n
+appender.0.layout.patternSelector.0.type = PatternMatch
+appender.0.layout.patternSelector.0.key = NoLocation
+appender.0.layout.patternSelector.0.pattern = [%-5level] %c{1.} %msg%n
+appender.0.layout.patternSelector.1.type = PatternMatch
+appender.0.layout.patternSelector.1.key = Flow
+appender.0.layout.patternSelector.1.pattern = [%-5level] %c{1.} ====== %C{1.}.%M:%L %msg ======%n
 
 rootLogger.level = WARN
 rootLogger.appenderRef.0.ref = CONSOLE
martind@stormy:~/tmp/D161042$ 

I didn't check whether it was the only instance of such a problem, sorry. I didn't even check whether there were any other problems in this file, let alone anything constructive such as why automated testing didn't catch this. I didn't find any other examples out on the internets. If I'm trying to provide search engine fodder, for the next poor sap, I should show the full presentation, which was this, once I'd got all my other problems out of the way:

Exception in thread "main" org.apache.logging.log4j.core.config.ConfigurationException: No type attribute provided for component patternMatch
	at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationBuilder.createComponent(PropertiesConfigurationBuilder.java:338)
	at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationBuilder.processRemainingProperties(PropertiesConfigurationBuilder.java:353)
	at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationBuilder.createComponent(PropertiesConfigurationBuilder.java:341)
	at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationBuilder.processRemainingProperties(PropertiesConfigurationBuilder.java:353)
	at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationBuilder.createLayout(PropertiesConfigurationBuilder.java:330)
	at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationBuilder.createAppender(PropertiesConfigurationBuilder.java:223)
	at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationBuilder.build(PropertiesConfigurationBuilder.java:155)
	at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationFactory.getConfiguration(PropertiesConfigurationFactory.java:56)
	at org.apache.logging.log4j.core.config.properties.PropertiesConfigurationFactory.getConfiguration(PropertiesConfigurationFactory.java:34)
	at org.apache.logging.log4j.core.config.ConfigurationFactory$Factory.getConfiguration(ConfigurationFactory.java:544)
	at org.apache.logging.log4j.core.config.ConfigurationFactory$Factory.getConfiguration(ConfigurationFactory.java:463)
	at org.apache.logging.log4j.core.config.ConfigurationFactory.getConfiguration(ConfigurationFactory.java:321)
	at org.apache.logging.log4j.core.LoggerContext.reconfigure(LoggerContext.java:719)
	at org.apache.logging.log4j.core.LoggerContext.reconfigure(LoggerContext.java:749)
	at org.apache.logging.log4j.core.LoggerContext.start(LoggerContext.java:261)
	at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactory.java:153)
	at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactory.java:46)
	at org.apache.logging.log4j.LogManager.getContext(LogManager.java:138)
	at org.apache.logging.log4j.spi.AbstractLoggerAdapter.getContext(AbstractLoggerAdapter.java:136)
	at org.apache.commons.logging.impl.Log4jApiLogFactory$LogAdapter.getContext(Log4jApiLogFactory.java:161)
	at org.apache.logging.log4j.spi.AbstractLoggerAdapter.getLogger(AbstractLoggerAdapter.java:46)
	at org.apache.commons.logging.impl.Log4jApiLogFactory.getInstance(Log4jApiLogFactory.java:210)
	at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:933)

[ppkarwasz]

@martin-dorey-hv,

Nice catch! 💯 Could you submit a PR to fix the problem?

I didn't even check whether there were any other problems in this file, let alone anything constructive such as why automated testing didn't catch this.

We didn't integrate our code examples into our unit test suite. The log4j2.properties we converted manually from our log4j2.xml examples (which is the recommended format). Since the Java System properties configuration format is not used by the Log4j dev team and has a lot of quirks, you might find many typos in the examples.

[ppkarwasz]

BTW: the PropertiesConfigurationFactory should not throw, when it encounters an invalid configuration file, but log an ERROR to the status logger. I reported this as #3088.