I am writing a terminal application, which, after passing in -v option, gets, unsurprisingly, verbose. I want to have the output available in the terminal, for easy testing (it gets redirected to a log file when running as cron anyways).
However, python logging module doesn't allow me to write out the messages with corresponding levels when using a formatter. (Formatter is copied directly from Python Logging Cookbok)
This behavior is not limited to Python3 only. Python2.7 raises the same exception under the given conditions.
one.py
from sys import stdout
import logging
if __name__ == '__main__':
level = 20
log = logging.getLogger()
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
handler = logging.StreamHandler(stdout).setFormatter(formatter)
log.addHandler(handler)
log.setLevel(level)
log.info("Blah")
one.py output
Traceback (most recent call last):
File "/home/tlevi/PycharmProjects/untitled/main.py", line 14, in <module>
log.info("Blah")
File "/usr/lib/python3.4/logging/__init__.py", line 1279, in info
self._log(INFO, msg, args, **kwargs)
File "/usr/lib/python3.4/logging/__init__.py", line 1414, in _log
self.handle(record)
File "/usr/lib/python3.4/logging/__init__.py", line 1424, in handle
self.callHandlers(record)
File "/usr/lib/python3.4/logging/__init__.py", line 1485, in callHandlers
if record.levelno >= hdlr.level:
AttributeError: 'NoneType' object has no attribute 'level'
two.py (works like a charm)
from sys import stdout
import logging
if __name__ == '__main__':
level = 20
log = logging.getLogger()
handler = logging.StreamHandler(stdout)
log.addHandler(handler)
log.setLevel(level)
log.info("Blah")
two.py output
Blah