$level
$level :
Injects line/file:class/function where the log message came from
Warning: This only works if the handler processes the logs directly. If you put the processor on a handler that is behind a FingersCrossedHandler for example, the processor will only be called once the trigger level is reached, and all the log records will have the same file/line/.. data from the call that triggered the FingersCrossedHandler.