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Python logging format

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You have to use a custom Formatter class to get the logging format in Python. They are responsible for converting a LogRecord to (usually) a string that can be interpreted by either a human or an external system.

Read more: https://docs.python.org/3/library/logging.html#formatter-objects

Python logging format

Simple example code where the logging format is modified depending on the message log level.

import logging


class CustomFormatter(logging.Formatter):
    grey = "\x1b[38;20m"
    yellow = "\x1b[33;20m"
    red = "\x1b[31;20m"
    bold_red = "\x1b[31;1m"
    reset = "\x1b[0m"
    format = "%(asctime)s - %(name)s - %(levelname)s - %(message)s (%(filename)s:%(lineno)d)"

    FORMATS = {
        logging.DEBUG: grey + format + reset,
        logging.INFO: grey + format + reset,
        logging.WARNING: yellow + format + reset,
        logging.ERROR: red + format + reset,
        logging.CRITICAL: bold_red + format + reset
    }

    def format(self, record):
        log_fmt = self.FORMATS.get(record.levelno)
        formatter = logging.Formatter(log_fmt)
        return formatter.format(record)


# create logger with 'spam_application'
logger = logging.getLogger("My_app")
logger.setLevel(logging.DEBUG)

# create console handler with a higher log level
ch = logging.StreamHandler()
ch.setLevel(logging.DEBUG)

ch.setFormatter(CustomFormatter())

logger.addHandler(ch)

logger.debug("debug message")
logger.info("info message")
logger.warning("warning message")
logger.error("error message")
logger.critical("critical message")

Output:

Python logging format

Source: https://stackoverflow.com/questions/384076/

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

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