Python3 multiprocessing loggin example.

multiprocessing-logging.py

#!/usr/bin/env python3

import logging
import multiprocessing


def create_logger():
    logger = multiprocessing.get_logger()
    logger.setLevel(logging.INFO)
    formatter = logging.Formatter(\
        '[%(asctime)s| %(levelname)s| %(processName)s] %(message)s')
    handler = logging.FileHandler(f'{__file__}.log')
    handler.setFormatter(formatter)

    # this bit will make sure you won't have
    # duplicated messages in the output
    if not len(logger.handlers):
        logger.addHandler(handler)
    return logger


def worker(id):
    logger = create_logger()
    logger.info(f'process {id} checking in')


if __name__ == '__main__':
    count = 5

    logger = create_logger()
    logger.info('starting pool')

    with multiprocessing.Pool(count) as pool:
        pool.map(worker, [x for x in range(10)])