NiFi custom processor custom log, logging in two places - apache-nifi

Question

NiFi 1.2.0
I am having a custom processor and I wish to have a dedicated log file for the same. Accordingly, I have configured the com.datalake.processors.SQLServerCDCProcessor class to use an appender named 'SQLSERVER-CDC'
Following is the logback.xml :
<?xml version="1.0" encoding="UTF-8"?>
<configuration scan="true" scanPeriod="30 seconds">
<contextListener class="ch.qos.logback.classic.jul.LevelChangePropagator">
<resetJUL>true</resetJUL>
</contextListener>
<appender name="APP_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>/var/log/nifi/nifi-app.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<!--
For daily rollover, use 'app_%d.log'.
For hourly rollover, use 'app_%d{yyyy-MM-dd_HH}.log'.
To GZIP rolled files, replace '.log' with '.log.gz'.
To ZIP rolled files, replace '.log' with '.log.zip'.
-->
<fileNamePattern>/var/log/nifi/archive/nifi-app_%d{yyyy-MM-dd_HH}.%i.log</fileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>100MB</maxFileSize>
</timeBasedFileNamingAndTriggeringPolicy>
<!-- keep 30 log files worth of history -->
<maxHistory>3</maxHistory>
</rollingPolicy>
<encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
<pattern>%date %level [%thread] %logger{40} %msg%n</pattern>
</encoder>
<immediateFlush>true</immediateFlush>
</appender>
<appender name="USER_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>/var/log/nifi/nifi-user.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<!--
For daily rollover, use 'user_%d.log'.
For hourly rollover, use 'user_%d{yyyy-MM-dd_HH}.log'.
To GZIP rolled files, replace '.log' with '.log.gz'.
To ZIP rolled files, replace '.log' with '.log.zip'.
-->
<fileNamePattern>/var/log/nifi/archive/nifi-user_%d.log</fileNamePattern>
<!-- keep 30 log files worth of history -->
<maxHistory>3</maxHistory>
</rollingPolicy>
<encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
<pattern>%date %level [%thread] %logger{40} %msg%n</pattern>
</encoder>
</appender>
<appender name="BOOTSTRAP_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>/var/log/nifi/nifi-bootstrap.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<!--
For daily rollover, use 'user_%d.log'.
For hourly rollover, use 'user_%d{yyyy-MM-dd_HH}.log'.
To GZIP rolled files, replace '.log' with '.log.gz'.
To ZIP rolled files, replace '.log' with '.log.zip'.
-->
<fileNamePattern>/var/log/nifi/archive/nifi-bootstrap_%d.log</fileNamePattern>
<!-- keep 5 log files worth of history -->
<maxHistory>5</maxHistory>
</rollingPolicy>
<encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
<pattern>%date %level [%thread] %logger{40} %msg%n</pattern>
</encoder>
</appender>
<appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
<encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
<pattern>%date %level [%thread] %logger{40} %msg%n</pattern>
</encoder>
</appender>
<!-- Start : Added for log for custom processor -->
<appender name="SQLSERVER-CDC" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>/var/log/nifi/sqlserver-cdc.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<!--
For daily rollover, use 'app_%d.log'.
For hourly rollover, use 'app_%d{yyyy-MM-dd_HH}.log'.
To GZIP rolled files, replace '.log' with '.log.gz'.
To ZIP rolled files, replace '.log' with '.log.zip'.
-->
<fileNamePattern>/var/log/nifi/archive/sqlserver-cdc_%d{yyyy-MM-dd_HH}.%i.log</fileNamePattern>
<timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
<maxFileSize>25MB</maxFileSize>
</timeBasedFileNamingAndTriggeringPolicy>
<!-- keep 30 log files worth of history -->
<maxHistory>3</maxHistory>
</rollingPolicy>
<encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
<pattern>%date %level [%thread] %logger{40} %msg%n</pattern>
<immediateFlush>true</immediateFlush>
</encoder>
</appender>
<!-- End : Added for log for custom processor -->
<!-- valid logging levels: TRACE, DEBUG, INFO, WARN, ERROR -->
<logger name="org.apache.nifi" level="INFO"/>
<logger name="org.apache.nifi.processors" level="WARN"/>
<logger name="org.apache.nifi.processors.standard.LogAttribute" level="INFO"/>
<logger name="org.apache.nifi.controller.repository.StandardProcessSession" level="WARN" />
<logger name="org.apache.zookeeper.ClientCnxn" level="ERROR" />
<logger name="org.apache.zookeeper.server.NIOServerCnxn" level="ERROR" />
<logger name="org.apache.zookeeper.server.NIOServerCnxnFactory" level="ERROR" />
<logger name="org.apache.zookeeper.server.quorum" level="ERROR" />
<logger name="org.apache.zookeeper.ZooKeeper" level="ERROR" />
<logger name="org.apache.zookeeper.server.PrepRequestProcessor" level="ERROR" />
<logger name="org.apache.calcite.runtime.CalciteException" level="OFF" />
<logger name="org.apache.curator.framework.recipes.leader.LeaderSelector" level="OFF" />
<logger name="org.apache.curator.ConnectionState" level="OFF" />
<!-- Logger for managing logging statements for nifi clusters. -->
<logger name="org.apache.nifi.cluster" level="INFO"/>
<!-- Logger for logging HTTP requests received by the web server. -->
<logger name="org.apache.nifi.server.JettyServer" level="INFO"/>
<!-- Logger for managing logging statements for jetty -->
<logger name="org.eclipse.jetty" level="INFO"/>
<!-- Suppress non-error messages due to excessive logging by class or library -->
<logger name="com.sun.jersey.spi.container.servlet.WebComponent" level="ERROR"/>
<logger name="com.sun.jersey.spi.spring" level="ERROR"/>
<logger name="org.springframework" level="ERROR"/>
<!-- Suppress non-error messages due to known warning about redundant path annotation (NIFI-574) -->
<logger name="com.sun.jersey.spi.inject.Errors" level="ERROR"/>
<!--
Logger for capturing user events. We do not want to propagate these
log events to the root logger. These messages are only sent to the
user-log appender.
-->
<logger name="org.apache.nifi.web.security" level="INFO" additivity="false">
<appender-ref ref="USER_FILE"/>
</logger>
<logger name="org.apache.nifi.web.api.config" level="INFO" additivity="false">
<appender-ref ref="USER_FILE"/>
</logger>
<logger name="org.apache.nifi.authorization" level="INFO" additivity="false">
<appender-ref ref="USER_FILE"/>
</logger>
<logger name="org.apache.nifi.cluster.authorization" level="INFO" additivity="false">
<appender-ref ref="USER_FILE"/>
</logger>
<logger name="org.apache.nifi.web.filter.RequestLogger" level="INFO" additivity="false">
<appender-ref ref="USER_FILE"/>
</logger>
<!--
Logger for capturing Bootstrap logs and NiFi's standard error and standard out.
-->
<logger name="org.apache.nifi.bootstrap" level="INFO" additivity="false">
<appender-ref ref="BOOTSTRAP_FILE" />
</logger>
<logger name="org.apache.nifi.bootstrap.Command" level="INFO" additivity="false">
<appender-ref ref="CONSOLE" />
<appender-ref ref="BOOTSTRAP_FILE" />
</logger>
<!-- Everything written to NiFi's Standard Out will be logged with the logger org.apache.nifi.StdOut at INFO level -->
<logger name="org.apache.nifi.StdOut" level="INFO" additivity="false">
<appender-ref ref="BOOTSTRAP_FILE" />
</logger>
<!-- Everything written to NiFi's Standard Error will be logged with the logger org.apache.nifi.StdErr at ERROR level -->
<logger name="org.apache.nifi.StdErr" level="ERROR" additivity="false">
<appender-ref ref="BOOTSTRAP_FILE" />
</logger>
<!-- Start : Added for log for custom processor -->
<logger name="com.datalake.processors.SQLServerCDCProcessor" level="DEBUG" >
<appender-ref ref="SQLSERVER-CDC"/>
</logger>
<!-- End : Added for log for custom processor -->
<root level="INFO">
<appender-ref ref="APP_FILE"/>
</root>
</configuration>
The strange fact is that the custom processor debug statements are written to both 'nifi-app.log' and the 'sqlserver-cdc.log' but I want these statements to be written only in the latter('sqlserver-cdc.log').
What am I missing ?

Answer 1

I think the problem is that com.datalake.processors.SQLServerCDCProcessor is also subject to the root logger configuration. You may be able to fix this by adding additivity="false":
<logger name="com.datalake.processors.SQLServerCDCProcessor" level="DEBUG" additivity="false" >
<appender-ref ref="SQLSERVER-CDC"/>
</logger>
See Lockback exclude logger from root for more on additivity vs. the root logger.