Log4j2 Custom RolloverStrategy - log4j2

Question

Is there a way to write a custom RolloverStrategy in log4j2? I want to delete old files over 14 days and log4j2 currently doesn't support it (https://issues.apache.org/jira/browse/LOG4J2-524).
I wrote a custom Strategy and tried to implement RolloverStrategy interface but I don't see it being triggered on file rollover.

Answer 1

I got it working...I had to annotate my class with #Plugin as shown below:
#org.apache.logging.log4j.core.config.plugins.Plugin(name = "DeleteMaxAgeFilesStrategy", category = "Core", printObject = true)
public class DeleteMaxAgeFilesStrategy implements RolloverStrategy {
private static final Logger logger = LoggerFactory.getLogger(DeleteMaxAgeFilesStrategy.class);
private static final int DEFAULT_MAX_AGE = 14;
private final int maxAgeIndex;
public DeleteMaxAgeFilesStrategy(int maxAgeIndex) {
this.maxAgeIndex = maxAgeIndex;
}
#Override public RolloverDescription rollover(RollingFileManager manager) throws SecurityException {
purgeMaxAgeFiles(maxAgeIndex, manager);
return null;
}
#PluginFactory
public static DeleteMaxAgeFilesStrategy createStrategy(
#PluginAttribute("maxAge") final String maxAge) {
int maxAgeIndex = DEFAULT_MAX_AGE;
if (maxAge != null) {
maxAgeIndex = Integer.parseInt(maxAge);
}
return new DeleteMaxAgeFilesStrategy(maxAgeIndex);
}
/**
* Purge files older than defined maxAge. If file older than current date - maxAge delete them or else keep it.
*
* #param maxAgeIndex maxAge Index
* #param manager The RollingFileManager
*/
private void purgeMaxAgeFiles(final int maxAgeIndex, final RollingFileManager manager) {
String filename = manager.getFileName();
File file = new File(filename);
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, -maxAgeIndex);
Date cutoffDate = cal.getTime();
if (file.getParentFile().exists()) {
filename = file.getName().replaceAll("\\..*", "");
File[] files = file.getParentFile().listFiles(
new StartsWithFileFilter(filename, false));
for (int i = 0; i < files.length; i++) {
try {
BasicFileAttributes attr = Files.readAttributes(files[i].toPath(), BasicFileAttributes.class);
if (new Date(attr.creationTime().toMillis()).before(cutoffDate)) {
files[i].delete();
}
} catch (Exception e) {
logger.error("Unable to delete old log files at rollover", e);
}
}
}
}
class StartsWithFileFilter implements FileFilter {
private final String startsWith;
private final boolean inclDirs;
public StartsWithFileFilter(String startsWith, boolean includeDirectories) {
super();
this.startsWith = startsWith.toUpperCase();
inclDirs = includeDirectories;
}
/*
* (non-Javadoc)
*
* #see java.io.FileFilter#accept(java.io.File)
*/
public boolean accept(File pathname) {
if (!inclDirs && pathname.isDirectory()) {
return false;
} else
return pathname.getName().toUpperCase().startsWith(startsWith);
}
}
}
and here's my log4j2.xml config:
<RollingFile name="FileOut" fileName="${sys:application.log.path}/restly-api.log"
filePattern="${sys:application.log.path}/restly-api-%d{yyyy-MM-dd}.gz">
<PatternLayout pattern="%date{yyyy/MM/dd HH:mm:ss.SSS} %-5level [%t] [%logger{36}] %msg%n"/>
<Policies>
<TimeBasedTriggeringPolicy interval="1" modulate="true"/>
</Policies>
<DeleteMaxAgeFilesStrategy maxAge="14"/>
</RollingFile>
Note: Log4j2 has implemented this feature in 2.6 release