What Could Cause The Logging Module To Log A Record Multiple Times?

I have a multi-threaded Python application that makes use of the built in logging module. To control the logging levels and make it easier to swap the StreamHandler with a FileHan

Solution 1:

My guess is that you've got multiple handlers (ie, one message is being emitted multiple times; but on re-reading your question, it looks like you already knew that). To debug that, try:

• Looking at logging.getLogger("").handlers (ie, the handlers on the root logger)
• Checking your calls to addHandler()
• Brandon Rhode's logging_tree module
• Use pdb to trace a log message's lifecycle (ie, put a breakpoint just before a call to self._logger.info(…), then step into that function).