KodoBlog | tech practice & philosophy

Python logging example and helper

When trying to find simple example on how to use Python logging module for writing logs to file, I became frustrated, as there are only a few useful examples. Here’s one that really works and covers most of use cases: see it on mechanicalcat.net.

And here’s simple helper to open log file, based on that example:

import re
import logging

def openlog(filename, logger_name=None, level=logging.DEBUG, format='%(asctime)s %(levelname)s %(message)s'):
    if not logger_name:
        logger_name = filename[filename.rfind('/')+1:]
    logger = logging.getLogger(logger_name)
    handler = logging.FileHandler(filename)
    formatter = logging.Formatter(format)
    handler.setFormatter(formatter)
    logger.addHandler(handler)
    logger.setLevel(level)
    return logger

So, you can simply use this helper like this:

logger = openlog('/var/log/just_a_test.log')
logger.debug("hello, i'm debug message!")

Actually, basic examples are provided in docs. I missed them first time, because reference seems to be complicated at start point.