How to programatically access appenders from logback-access config? - logback

Question

I have enabled logback-access log for Tomcat 7.0, using LogbackValve.
My logback-access config looks like this.
<configuration>
<appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<file>access.log</file>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>access.%d{yyyy-MM-dd}.log.zip</fileNamePattern>
</rollingPolicy>
<encoder>
<pattern>combined</pattern>
</encoder>
</appender>
<appender-ref ref="FILE" />
</configuration>
Now this works perfect and I can see access logs. But in some other code I want to retrieve the appender configured in logback-access.xml programmatically. Is there a way to do it. Since there are no Loggers defined , you cannot use LoggerContext .

Answer 1

You can use LogbackAccessContext to retrieve the appenders configured in logback-access.xml. This is my solution:
TomcatServletWebServerFactory sc = (TomcatServletWebServerFactory) context.getBean(TomcatServletWebServerFactory.class);
List<Valve> values = (List<Valve>) sc.getEngineValves();
LogbackAccessTomcatValve accessTomcatValve = null;
for(Valve value : values) {
if(value.getClass() == LogbackAccessTomcatValve.class) {
accessTomcatValve = (LogbackAccessTomcatValve) value;
}
}
//get logbackAccessContext from the logbackAccessTomcatValve by invoking.
LogbackAccessContext logbackAccessContext = null;
Field field = null;
try {
field = accessTomcatValve.getClass().getDeclaredField("logbackAccessContext");
field.setAccessible(true);
logbackAccessContext = (LogbackAccessContext) field.get(accessTomcatValve);
} catch (Exception e) {
log.error("Exception happened when fetching the logback access context ." +e.getMessage());
}