I'm using Python 3.3.5 and the logging module to log information to a local file (from different threads). There are cases where I'd like to output some additional information, without knowing exactly what that information will be (e.g. it might be one single line of text or a dict).
What I'd like to do is add this additional information to my log file, after the log record has been written. Furthermore, the additional info is only necessary when the log level is error (or higher).
Ideally, it would look something like:
2014-04-08 12:24:01 - INFO - CPU load not exceeded
2014-04-08 12:24:26 - INFO - Service is running
2014-04-08 12:24:34 - ERROR - Could not find any active server processes
Additional information, might be several lines.
Dict structured information would be written as follows:
key1=value1
key2=value2
2014-04-08 12:25:16 - INFO - Database is responding
Short of writing a custom log formatter, I couldn't find much which would fit my requirements. I've read about filters and contexts, but again this doesn't seem like a good match.
Alternatively, I could just write to a file using the standard I/O, but most of the functionality already exists in the Logging module, and moreover it's thread-safe.
Any input would be greatly appreciated. If a custom log formatter is indeed necessary, any pointers on where to start would be fantastic.
I just add \n symbols to the output text.