Python logging current username

logger-username.py

import coloredlogs # OPTIONAL (see end of the file)
import getpass
import logging
import logging.handlers

#
# The logger and the logging level
#
logger = logging.getLogger('mylogger')
logger.setLevel(logging.DEBUG)

#
# Log to console and a rotating file
# (10MB per log file, max 5 log files)
#
ch = logging.StreamHandler()
fh = logging.handlers.RotatingFileHandler('mylogger.log', maxBytes=10*1024*1024, backupCount=5)
logger.addHandler(ch)
logger.addHandler(fh)

#
# Username filter
# (to add current username to logging format)
#
class UsernameFilter(logging.Filter):
    def filter(self, record):
        record.username = getpass.getuser()
        return True
logger.addFilter(UsernameFilter())

#
# Logging format
#
fmt = '%(asctime)s %(username)-15s %(module)-15s %(levelname)-15s %(message)s'
datefmt = '%Y-%m-%d %H:%M:%S'
formatter = logging.Formatter(fmt, datefmt)
ch.setFormatter(formatter)
fh.setFormatter(formatter)

#
# OPTIONAL: colored logs for console only (requires coloredlogs package)
# (remove lines if not needed)
#
colored_formatter = coloredlogs.ColoredFormatter(fmt, datefmt)
ch.setFormatter(colored_formatter)

#
# Logging test
#
logger.debug('debug message')
logger.info('info message')
logger.warning('warn message')
logger.error('error message')
logger.critical('critical message')

Output:

$ python3.7 logger.py 
2021-09-02 17:04:12 insideshell     logger          DEBUG           debug message
2021-09-02 17:04:12 insideshell     logger          INFO            info message
2021-09-02 17:04:12 insideshell     logger          WARNING         warn message
2021-09-02 17:04:12 insideshell     logger          ERROR           error message
2021-09-02 17:04:12 insideshell     logger          CRITICAL        critical message

$ cat mylogger.log 
2021-09-02 17:04:12 insideshell     logger          DEBUG           debug message
2021-09-02 17:04:12 insideshell     logger          INFO            info message
2021-09-02 17:04:12 insideshell     logger          WARNING         warn message
2021-09-02 17:04:12 insideshell     logger          ERROR           error message
2021-09-02 17:04:12 insideshell     logger          CRITICAL        critical message

Colored output (if needed):