How to write to a file, using the logging Python module?

Question

How can I use the logging module in Python to write to a file? Every time I try to use it, it just prints out the message.

Answer 1

here's a simpler way to go about it. this solution doesn't use a config dictionary and uses a rotation file handler, like so:

import logging
from logging.handlers import RotatingFileHandler

logging.basicConfig(handlers=[RotatingFileHandler(filename=logpath+filename,
                     mode='w', maxBytes=512000, backupCount=4)], level=debug_level,
                     format='%(levelname)s %(asctime)s %(message)s', 
                    datefmt='%m/%d/%Y%I:%M:%S %p')

logger = logging.getLogger('my_logger')

or like so:

import logging
from logging.handlers import RotatingFileHandler

handlers = [
            RotatingFileHandler(filename=logpath+filename, mode='w', maxBytes=512000, 
                                backupCount=4)
           ]
logging.basicConfig(handlers=handlers, level=debug_level, 
                    format='%(levelname)s %(asctime)s %(message)s', 
                    datefmt='%m/%d/%Y%I:%M:%S %p')

logger = logging.getLogger('my_logger')

the handlers variable needs to be an iterable. logpath+filename and debug_level are just variables holding the respective info. of course, the values for the function params are up to you.

the first time i was using the logging module i made the mistake of writing the following, which generates an OS file lock error (the above is the solution to that):

import logging
from logging.handlers import RotatingFileHandler

logging.basicConfig(filename=logpath+filename, level=debug_level, format='%(levelname)s %(asctime)s %(message)s', datefmt='%m/%d/%Y
 %I:%M:%S %p')

logger = logging.getLogger('my_logger')
logger.addHandler(RotatingFileHandler(filename=logpath+filename, mode='w', 
                  maxBytes=512000, backupCount=4))

and Bob's your uncle!