[LOG4J2-2021] Complex sifting/routing appender configuration

• Type: Question
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.6
• Component/s: Appenders
• Assignee: Unassigned
• Reporter: Anton Johansson
• Created: 18/Aug/17 13:44
• Updated: 18/Aug/17 13:46

Description

We're currently in the process of upgrading some of our components, including upgrading from Log4J to Log4J2.

We previously had this configuration for splitting different logs to different files:

log4j.appender.File=org.apache.log4j.sift.MDCSiftingAppender
log4j.appender.File.key=instanceId
log4j.appender.File.default=Unspecified
log4j.appender.File.appender=org.apache.log4j.sift.MDCSiftingAppender
log4j.appender.File.appender.key=bundleName
log4j.appender.File.appender.default=unspecified
log4j.appender.File.appender.appender=org.apache.log4j.RollingFileAppender
log4j.appender.File.appender.appender.layout=org.apache.log4j.PatternLayout
log4j.appender.File.appender.appender.layout.ConversionPattern=%d

{ISO8601} | %-5.5p | %-16.16t | %-32.32c{1} | %X{bundle.id} - %X{bundle.name} - %X{bundle.version} | %m%n
log4j.appender.File.appender.appender.file=${karaf.data}/log/$\\{instanceId\\}/$
{bundleName\\}.log
log4j.appender.File.appender.appender.append=true
log4j.appender.File.appender.appender.maxFileSize=1MB
log4j.appender.File.appender.appender.maxBackupIndex=10

This means we get different folders for different customers (instanceId) and different files for different OSGi bundles (bundleName) within those folders. This is a pretty sweet setup. To do the same in Log4J2, with XML configuration, I had to do this:

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="INFO">
<Appenders>
<Routing name="Routing">
<Routes pattern="$${ctx:instanceId}">
<!-- Has the 'instanceId' key -->
<Route>
<Routing name="RoutingWithInstance">
<Routes pattern="$${ctx:bundleName}">
<!-- Has the 'bundleName' key -->
<Route>
<RollingFile name="Rolling-${ctx:bundle.name}" fileName="${sys:karaf.data}/log/${ctx:instanceId}/${ctx:bundleName}.log" filePattern="${sys:karaf.data}/log/${ctx:bundleName}.log.%i">
<PatternLayout>
<pattern>%d{ISO8601}

| %-5p | %X

{instanceId} | %-16t | %-32c{1} | %X{bundle.id} - %X{bundle.name} - %X{bundle.version} | %m%n</pattern>
</PatternLayout>
<Policies>
<SizeBasedTriggeringPolicy size="1MB" />
</Policies>
<DefaultRolloverStrategy max="9" />
</RollingFile>
</Route>

<!-- Missing the 'bundleName' key -->
<Route key="$${ctx:bundleName}">
<RollingFile name="Rolling-unspecified" fileName="${sys:karaf.data}/log/${ctx:instanceId}/unspecified.log" filePattern="${sys:karaf.data}/log/unspecified.log.%i">
<PatternLayout>
<pattern>%d{ISO8601} | %-5p | %X{instanceId}

| %-16t | %-32c

{1} | %X{bundle.id} - %X{bundle.name} - %X{bundle.version} | %m%n</pattern>
</PatternLayout>
<Policies>
<SizeBasedTriggeringPolicy size="1MB" />
</Policies>
<DefaultRolloverStrategy max="9" />
</RollingFile>
</Route>
</Routes>
</Routing>
</Route>

<!-- Missing the 'instanceId' key -->
<Route key="$${ctx:instanceId}">
<Routing name="RoutingWithoutInstance">
<Routes pattern="$${ctx:bundleName}">
<!-- Has the 'bundleName' key -->
<Route>
<RollingFile name="Rolling-${ctx:bundle.name}" fileName="${sys:karaf.data}/log/Unspecified/${ctx:bundleName}.log" filePattern="${sys:karaf.data}/log/${ctx:bundleName}.log.%i">
<PatternLayout>
<pattern>%d{ISO8601} | %-5p | %X{instanceId} | %-16t | %-32c{1}

| %X

{bundle.id} - %X{bundle.name} - %X{bundle.version} | %m%n</pattern>
</PatternLayout>
<Policies>
<SizeBasedTriggeringPolicy size="1MB" />
</Policies>
<DefaultRolloverStrategy max="9" />
</RollingFile>
</Route>

<!-- Missing the 'bundleName' key -->
<Route key="$${ctx:bundleName}">
<RollingFile name="Rolling-unspecified" fileName="${sys:karaf.data}/log/Unspecified/unspecified.log" filePattern="${sys:karaf.data}/log/unspecified.log.%i">
<PatternLayout>
<pattern>%d{ISO8601} | %-5p | %X{instanceId} | %-16t | %-32c{1} | %X{bundle.id}

- %X

{bundle.name}

- %X

{bundle.version}

| %m%n</pattern>
</PatternLayout>
<Policies>
<SizeBasedTriggeringPolicy size="1MB" />
</Policies>
<DefaultRolloverStrategy max="9" />
</RollingFile>
</Route>
</Routes>
</Routing>
</Route>
</Routes>
</Routing>
</Appenders>
<Loggers>
<Logger name="com.viskan" level="DEBUG" />
<Root level="INFO">
<AppenderRef ref="Routing" />
</Root>
</Loggers>
</Configuration>

This looks much more complex, and I have lots of redundant configurations (policies, strategies, layouts).

Is there an easier way to do this that I've missed?