[logback-user] Multiple FileAppenders writing to single file no longer working in Logback 1.2.3

20 Dec 2018

      Hello there Logback users. An application I’m responsible uses logback for its internal logging. It logs to various files at various levels. I’ve extended it successfully to reformat certain log messages and save them into a new log called “combined-audit.log”. This is all within a single JVM, logging to a file on a local filesystem.

The reason for the three loggers/appenders is that I want to log from three different packages, at different levels, filter each differently, and encode each differently. This is all necessary because I cannot make changes to the app itself, so I’m trying to use Logback to accomplish my needs.

The below configuration works in Logback 1.1.3 and not in Logback 1.2.3.

In Logback 1.2.3, only messages from one of the three loggers are logged to the single file. When I change the file name to three different files, messages from each logger are in each file.

I read through release notes from 1.1.3 to 1.2.3 and nothing jumped out at me as having the potential to change this behavior.

Is this a supported configuration in 1.2.3? Does anyone have any ideas for how to accomplish the objective?

<!-- Appends app audit messages to combined audit log -->
<appender name="COMBINED_AUDIT" class="ch.qos.logback.core.FileAppender">
    <File>${logging.directory}/combined-audit.log</File>

    <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
        <charset>UTF-8</charset>
        <Pattern>%date{ISO8601}|%mdc{m.remote_addr}|%mdc{m.jsessionid}||%msg%n</Pattern>
    </encoder>
</appender>

<logger name="j.k.l" level="ALL" additivity="false">
    <appender-ref ref="COMBINED_AUDIT"/>
</logger>

<!-- Appends LDAP auth messages to combined audit log -->
<appender name="COMBINED_LDAP" class="ch.qos.logback.core.FileAppender">
    <File>${logging.directory}/combined-audit.log</File>

    <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
        <charset>UTF-8</charset>
        <Pattern>%date{ISO8601}|%mdc{m.remote_addr}|%mdc{m.jsessionid}|%replace(%replace(%replace(%msg){'^.*resultCode=',''}){',.*identifier=','|'}){', context=.*$',''}|LDAP|||%n</Pattern>
    </encoder>

    <filter class="ch.qos.logback.core.filter.EvaluatorFilter">
        <evaluator>
            <expression>return message.contains("authenticate response=");</expression>
        </evaluator>
        <OnMatch>ACCEPT</OnMatch>
        <OnMismatch>DENY</OnMismatch>
    </filter>
</appender>

<logger name="a.b.c.d" level="DEBUG" additivity="false">
    <appender-ref ref="COMBINED_LDAP"/>
</logger>

<!-- Appends LDAP invalid username messages to combined audit log -->
<appender name="COMBINED_INVALID_USERNAME" class="ch.qos.logback.core.FileAppender">
    <File>${logging.directory}/combined-audit.log</File>

    <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
        <charset>UTF-8</charset>
        <Pattern>%date{ISO8601}|%mdc{m.remote_addr}|%mdc{m.jsessionid}|INVALID_USERNAME||LDAP|||%n</Pattern>
    </encoder>

    <filter class="ch.qos.logback.core.filter.EvaluatorFilter">
        <evaluator>
            <expression>return message.contains("failed using filter=");</expression>
        </evaluator>
        <OnMatch>ACCEPT</OnMatch>
        <OnMismatch>DENY</OnMismatch>
    </filter>
</appender>

<logger name="v.w.x.y.z" level="INFO" additivity="false">
    <appender-ref ref="COMBINED_INVALID_USERNAME"/>
</logger>

[logback-user] Multiple FileAppenders writing to single file no longer working in Logback 1.2.3

John Morton