Overriding logback configurations

logback, logging, slf4j

Solution

I don't think that you can overwrite `logback.xml`-definitions from an included file.

But I have an approach that solves your question regarding overriding the root-logger-level, using variable substitution with default values:

logback.xml

<configuration>
  <include file="includedFile.xml" />

  <!-- STDOUT appender stuff -->

  <root level="${root.level:-DEBUG}">
    <appender-ref ref="STDOUT" />
  </root>
<configuration>

includedFile.xml

<included>

  <!-- override the default value; or comment out to leave it at default -->
  <property name="root.level" value="INFO" />

</included>

With that concept, I've even been able to control the output to multiple appenders from the included file:

logback.xml

<configuration>
  <include file="includedFile.xml" />

  <!-- STDOUT appender stuff -->

  <appender name="FILE" class="ch.qos.logback.core.FileAppender">
    <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
      <level>${file.level:-ALL}</level>
    </filter>
    <file>/path/to/logfeil.log</file>
    <encoder>
      <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
    </encoder>
  </appender>

  <appender name="SYSLOG" class="ch.qos.logback.classic.net.SyslogAppender">
    <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
      <level>${syslog.level:-OFF}</level>
    </filter>
    <syslogHost>localhost</syslogHost>
    <facility>${syslog.facility:-LOCAL1}</facility>
    <suffixPattern>${syslog.pattern:-[%thread] %logger{36} - %msg}</suffixPattern>
   </appender>

  <logger name="my.package" level="${logging.level:-INFO}" additivity="false">
    <appender-ref ref="FILE" />
    <appender-ref ref="SYSLOG" />
  </logger>

  <root level="${root.level:-DEBUG}">
    <appender-ref ref="STDOUT" />
  </root>
<configuration>

And in the `includedFile.xml` I can control if, and at what level message shall pass through the appenders `FILE` and `SYSLOG`, setting the properties `file.level`, `syslog.level` and of course `logging.level`.

Problem

Is there any way that we can override the logback configurations? I know that we define the logback configurations in file named `logback.xml` (usually stored in the path `src/main/resources`) and I know that by using `<include>` tag we can set an external file to be added to `logback.xml` just like below: ``` <configuration> <!--<include url="file:///d:/ServerConfig.xml"/>--> <include file="${outPut}/ServerConfig.xml"/> <logger name="Server" LEVEL="DEBUG"> <appender-ref ref="FILEOUT" /> </logger> <root level="DEBUG"> <appender-ref ref="STDOUT" /> <!--<appender-ref ref="FILEOUT" />--> </root> </configuration> ``` But what if I want to override this default configuration? For example set the root logger level to INFO. Here is the included file: ``` <included> <!-- <property file="d:/ServerSysVar.properties"/>--> <property file="${outPut}/ServerSysVar.properties"/> <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender"> <!-- encoders are assigned the type ch.qos.logback.classic.encoder.PatternLayoutEncoder by default --> <encoder> <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern> </encoder> </appender> <appender name="FILEOUT" class="ch.qos.logback.core.FileAppender"> <file>${Sys_Location}/Serverfile4.log</file> <!-- encoders are assigned the type ch.qos.logback.classic.encoder.PatternLayoutEncoder by default --> <encoder> <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} %class{36}.%M %L CLIENT_PORT:%X{ClientPort}- %msg%n</pattern> </encoder> </appender> <logger name="Service" LEVEL="DEBUG"> <appender-ref ref="FILEOUT" /> </logger> <root> <appender-ref ref="STDOUT" /> <!-- <appender-ref ref="FILEOUT" />--> </root> </included> ```

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