Python logging basicConfig

Python logging basicConfig configures the root logger. You can configure the logging system by creating a stream handler with a default format.

logging.basicConfig(filename='test.log', format='%(filename)s: %(message)s',
    level=logging.DEBUG)

The debug, info, warning, error and critical call basicConfig automatically if no handlers are defined for the root logger.

Python logging basicConfig example

Simple example code.

import logging

logging.basicConfig(filename='test.log', format='%(filename)s: %(message)s',
                    level=logging.DEBUG)

logging.debug('This is a debug message')
logging.info('This is an info message')
logging.warning('This is a warning message')
logging.error('This is an error message')
logging.critical('This is a critical message')

Output:

You can remove the default handlers and reconfigure logging like this:

# if someone tried to log something before basicConfig is called, Python creates a default handler that
# goes to the console and will ignore further basicConfig calls. Remove the handler if there is one.
root = logging.getLogger()
if root.handlers:
    for handler in root.handlers:
        root.removeHandler(handler)
logging.basicConfig(format='%(asctime)s %(message)s',level=logging.DEBUG)

Do comment if you have any doubts or suggestions on this Python log topic.

Note: IDE: PyCharm 2021.3.3 (Community Edition)

Windows 10

Python 3.10.1

All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.