toys/utils/logger_test.py

#!/usr/bin/env python3
# -*- coding: utf-8; mode: python; tab-width: 4; indent-tabs-mode: nil -*-
# vim: tabstop=4 expandtab shiftwidth=4 softtabstop=4 fileencoding=utf-8

import logging
import logging.handlers


# Format string
FORMAT_STRING = '[%(asctime)s][%(levelname)s][%(filename)s:%(lineno)d][%(funcName)s][%(name)s] %(message)s'
ENABLE_LOG = True
DEFAULT_LEVEL = logging.DEBUG
SAVE_LOG_FILE = False

# Create a singleton of logger
class Logger():
    __instance = None
    @staticmethod
    def get_instance():
        """ Static access method. """
        if Logger.__instance == None:
            Logger()
        return Logger.__instance

    def __init__(self):
        """ Virtually private constructor. """
        if Logger.__instance != None:
            raise Exception("This class is a singleton!")
        else:
            Logger.__instance = self

            if not ENABLE_LOG:
                logging.disable(logging.CRITICAL)
            else:
                logging.disable(logging.NOTSET)
                # Initialize configuration
                logging.basicConfig(format=FORMAT_STRING)
                if SAVE_LOG_FILE:
                    # Save log information into file
                    fileshandle = logging.handlers.RotatingFileHandler('my_log')
                    # Set the default log level
                    fileshandle.setLevel(DEFAULT_LEVEL)
                    formatter = logging.Formatter(FORMAT_STRING)
                    fileshandle.setFormatter(formatter)
                    # Save log into file for the default root logger
                    logging.getLogger('').addHandler(fileshandle)
                logging.getLogger('').setLevel(DEFAULT_LEVEL)

Logger.get_instance()

D = logging.debug
I = logging.info
E = logging.error
W = logging.warning
C = logging.critical

class MyLogger():
    def __init__(self, name):
        self.__logger = logging.getLogger(name)
        self.__dict__['D'] = self.__logger.debug
        self.__dict__['I'] = self.__logger.info
        self.__dict__['E'] = self.__logger.error
        self.__dict__['W'] = self.__logger.warning
        self.__dict__['C'] = self.__logger.critical

        self.__logger.setLevel(logging.ERROR)

if __name__ == '__main__':
    def test():
        D(f"Only test: {__name__}")
        I(f"Only test: {__name__}")
        E(f"Only test: {__name__}")
        W(f"Only test: {__name__}")
        C(f"Only test: {__name__}")
    test()

    logger = MyLogger("mylogger")
    logger.D(f"Only test: {__name__}")
    logger.I(f"Only test: {__name__}")
    logger.E(f"Only test: {__name__}")
    logger.W(f"Only test: {__name__}")
    logger.C(f"Only test: {__name__}")