Log rotation enhancements in 5.3
When you specify the name of any of the following log files:
Main correlator log
Correlator input log
Any EPL log files
You can now use one, two or all three of the following string substitutions in any order:
${START_TIME}
${ROTATION_TIME}
${ID}
In the previous release, string substitutions were allowed for only the name of the input log file. Also, this release adds the ${ROTATION_TIME} string substitution. For example, to specify an EPL log filename for messages generated in com.example.mypackge, you could specify the log filename as follows:
mypackage_${ID}_${ROTATION_TIME}.log
The format is as follows:
file[one_or_more_substitutions_in_any_order].log
file | Replace file with the name of the file that you want to be the log file. If you also specify ${START_TIME} and/or ${ROTATION_TIME} and/or ${ID}, the correlator prefixes the name you specify to the time the correlator was started and/or the time the log file was rotated (logging to a new file began) and/or an ID, beginning with 001. |
${START_TIME} | Tag that indicates that you want the correlator to insert the date and time that it started into the log filename. |
${ROTATION_TIME} | Tag that indicates that you want the correlator to insert the date and time that it starts sending messages to a new log file into the log filename. |
${ID} | Tag that indicates that you want the correlator to insert a three-digit ID into the filename of the log file. The ID that the correlator inserts first is 001. The log ID increment is related only to rotation of log files. The ID allows you to create a sequence of log files. Each time the log file is rotated, the correlator increments the ID. |
If you plan to rotate log files then be sure to specify ${ROTATION_TIME} or ${ID}. You can also specify both.
Apama 5.3 provides two new interfaces for rotating all Apama log files. Log file rotation means that the log file in use is closed and a new log file begins to be used. Each of the following new interfaces rotates the main correlator log, correlator input log if the correlator is generating one, and any EPL log files.
The
engine_management utility now takes the following option:
engine_management -r rotateLogs
In an EPL monitor that uses the Management interface correlator plug-in, you can now call the
rotateLogs() action. The
rotateLogs() action is defined in the
com.apama.correlator.Logging event.