"handlers": {
        "console":{
            "class":"study.MyLogHandler",
            "formatter":"brief",
            "level":"INFO"
        },
        "file": {
            "class": "logging.handlers.RotatingFileHandler",
            "formatter": "precise",
      "filename": "logconfig.log",
      "maxBytes": 1024,
      "backupCount": 3
        }
    }

study.py

#!/usr/bin/env python
# -*- coding:utf-8 -*-


'''
@CreateTime: 2020/12/29 14:08
@Author : shouke
'''

import logging
import logging.config

LOGGING_CONFIG = {
    "version": 1,
    "formatters": {
        "default": {
            'format':'%(asctime)s %(filename)s %(lineno)s %(levelname)s %(message)s',
        },
        "plain": {
            "format": "%(message)s",
        },
    },
    "handlers": {
        "console": {
            "class": "logging.StreamHandler",
            "level": "INFO",
            "formatter": "default",
        },
        "console_plain": {
            "class": "logging.StreamHandler",
            "level":logging.INFO,
            "formatter": "plain"
        },
        "file":{
            "class": "logging.FileHandler",
            "level":20,
            "filename": "./log.txt",
            "formatter": "default",
        }
    },
    "loggers": {
        "console_logger": {
            "handlers": ["console"],
            "level": "INFO",
            "propagate": False,
        },
        "console_plain_logger": {
            "handlers": ["console_plain"],
            "level": "DEBUG",
            "propagate": False,
        },
        "file_logger":{
            "handlers": ["file"],
            "level": "INFO",
            "propagate": False,
        }
    },
    "disable_existing_loggers": True,
}

# 运行测试
logging.config.dictConfig(LOGGING_CONFIG)
logger = logging.getLogger("console_logger")
logger.debug('debug message')
logger.info('info message')
logger.warn('warning message')
logger.error('error message')
logger.critical('critical message')

LOGGING_CONFIG = {
    "version": 1,
    "formatters": {
        "default": {
            'format':'%(asctime)s %(filename)s %(lineno)s %(levelname)s %(message)s',
        }
    },
    "handlers": {
        "console": {
            "class": "logging.StreamHandler",
            "level": "INFO",
            "formatter": "default",
        }
    },
    "disable_existing_loggers": True,
    "root": {
        "handlers": ["console"],
        "level": "DEBUG"
    },
}

# 运行测试
logging.config.dictConfig(LOGGING_CONFIG)
logger = logging.getLogger("root")
logger.debug('debug message')
logger.info('info message')
logger.warn('warning message')
logger.error('error message')
logger.critical('critical message')

class Logger(Filterer):  
    #...略  

    def debug(self, msg, *args, **kwargs):
        """
        Log 'msg % args' with severity 'DEBUG'.

        To pass exception information, use the keyword argument exc_info with
        a true value, e.g.

        logger.debug("Houston, we have a %s", "thorny problem", exc_info=1)
        """
        if self.isEnabledFor(DEBUG):
            self._log(DEBUG, msg, args, **kwargs)

    def info(self, msg, *args, **kwargs):
        """
        Log 'msg % args' with severity 'INFO'.

        To pass exception information, use the keyword argument exc_info with
        a true value, e.g.

        logger.info("Houston, we have a %s", "interesting problem", exc_info=1)
        """
        if self.isEnabledFor(INFO):
            self._log(INFO, msg, args, **kwargs)
    
    #...略 

    def _log(self, level, msg, args, exc_info=None, extra=None, stack_info=False):
        """
        Low-level logging routine which creates a LogRecord and then calls
        all the handlers of this logger to handle the record.
        """
        sinfo = None
        if _srcfile:
            #IronPython doesn't track Python frames, so findCaller raises an
            #exception on some versions of IronPython. We trap it here so that
            #IronPython can use logging.
            try:
                fn, lno, func, sinfo = self.findCaller(stack_info)
            except ValueError: # pragma: no cover
                fn, lno, func = "(unknown file)", 0, "(unknown function)"
        else: # pragma: no cover
            fn, lno, func = "(unknown file)", 0, "(unknown function)"
        if exc_info:
            if isinstance(exc_info, BaseException):
                exc_info = (type(exc_info), exc_info, exc_info.__traceback__)
            elif not isinstance(exc_info, tuple):
                exc_info = sys.exc_info()
        record = self.makeRecord(self.name, level, fn, lno, msg, args,
                                 exc_info, func, extra, sinfo)
        self.handle(record)

    def handle(self, record):
        """
        Call the handlers for the specified record.

        This method is used for unpickled records received from a socket, as
        well as those created locally. Logger-level filtering is applied.
        """
        if (not self.disabled) and self.filter(record):
            self.callHandlers(record)


    def hasHandlers(self):
        """
        See if this logger has any handlers configured.

        Loop through all handlers for this logger and its parents in the
        logger hierarchy. Return True if a handler was found, else False.
        Stop searching up the hierarchy whenever a logger with the "propagate"
        attribute set to zero is found - that will be the last logger which
        is checked for the existence of handlers.
        """
        c = self
        rv = False
        while c:
            if c.handlers:
                rv = True
                break
            if not c.propagate:
                break
            else:
                c = c.parent
        return rv


    def callHandlers(self, record):
        """
        Pass a record to all relevant handlers.

        Loop through all handlers for this logger and its parents in the
        logger hierarchy. If no handler was found, output a one-off error
        message to sys.stderr. Stop searching up the hierarchy whenever a
        logger with the "propagate" attribute set to zero is found - that
        will be the last logger whose handlers are called.
        """
        c = self
        found = 0
        while c:
            for hdlr in c.handlers:
                found = found + 1
                if record.levelno >= hdlr.level:
                    hdlr.handle(record)
            if not c.propagate: 
                c = None    #break out
            else:
                c = c.parent
        if (found == 0):
            if lastResort:
                if record.levelno >= lastResort.level:
                    lastResort.handle(record)
            elif raiseExceptions and not self.manager.emittedNoHandlerWarning:
                sys.stderr.write("No handlers could be found for logger"
                                 " \"%s\"\n" % self.name)
                self.manager.emittedNoHandlerWarning = True