Python Logging Cheat Sheet

BasicLogger.py

'''
File: BasicLogger.py
Description: Logging cheat sheet.. You can find the documentation at 
             https://docs.python.org/3/library/logging.html.
'''

import logging
import SpecificLogger

# DEBUG: Detailed information, typically of interest only when diagnosing problems.
# INFO: Confirmation that things are working as expected.
# WARNING: An indication that something unexpected happened, or indicative of some problem in the near future (e.g. ‘disk space low’). The software is still working as expected.
# ERROR: Due to a more serious problem, the software has not been able to perform some function.
# CRITICAL: A serious error, indicating that the program itself may be unable to continue running.


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

def main() :
    logging.info("Starting logging application")

    result = SpecificLogger.add(10,20)
    logging.info("Result from add {}".format(result))

    result = SpecificLogger.multiply(10,20)
    logging.info("Result from multiply {}".format(result))

if __name__ == "__main__":
    main()

Logging.py

'''
File: Logging.py
Description: Logging module ment to reduce code in classes
'''

import logging

def setUpLogging(loggerName, level=logging.INFO) :
    '''
    loggerName: __name__
    '''
    logger = logging.getLogger(loggerName)
    logger.setLevel(level)
    formatter = logging.Formatter('%(levelname)s : %(name)s : %(message)s')

    # Sets up file handler
    fileHandler = logging.FileHandler(loggerName + ".log")
    fileHandler.setFormatter(formatter)

    # Sets up handler to std out
    streamHandler = logging.StreamHandler()
    streamHandler.setFormatter(formatter)
    streamHandler.setLevel(logging.DEBUG)

    # Adds handler to logger
    logger.addHandler(fileHandler)
    logger.addHandler(streamHandler)
    return logger

SpecificLogger.py

'''
File: SpecificLogger.py
Description: Use this to use logging to give your logger a unique name and include in
            in mulitple classes. You can find the documentation at 
             https://docs.python.org/3/library/logging.html.
'''

import Logging

# DEBUG: Detailed information, typically of interest only when diagnosing problems.
# INFO: Confirmation that things are working as expected.
# WARNING: An indication that something unexpected happened, or indicative of some problem in the near future (e.g. ‘disk space low’). The software is still working as expected.
# ERROR: Due to a more serious problem, the software has not been able to perform some function.
# CRITICAL: A serious error, indicating that the program itself may be unable to continue running.

logger = Logging.setUpLogging(__name__)

def add(x, y):
    result = x + y
    logger.info('Performing add: {} + {} = {}'.format(x, y, result)) 
    return result

def subtract(x, y):
    result = x - y
    logger.info('Performing subtract: {} - {} = {}'.format(x, y, result))
    return result

def multiply(x, y):
    result = x * y
    logger.info('Performing multiply: {} * {} = {}'.format(x, y, result))
    return result

def divide(x, y):
    result = x/y
    logger.info('Performing divide: {} / {} = {}'.format(x, y, result))
    return result


if __name__ == "__main__":
    add(10,20)
    subtract(10,20)