python对日志处理的封装

一个适应性范围较广的日志处理

# coding=utf8
"""
@author bfzs
"""
import os
import logging
from logging.handlers import TimedRotatingFileHandler, RotatingFileHandler
from cloghandler import ConcurrentRotatingFileHandler

format_dict = {
    1: logging.Formatter('%(asctime)s - %(name)s - %(lineno)d - %(levelname)s -  %(message)s', "%Y-%m-%d %H:%M:%S"),
    2: logging.Formatter('%(asctime)s - %(name)s - %(lineno)d - %(levelname)s -  %(message)s', "%Y-%m-%d %H:%M:%S"),
    3: logging.Formatter('%(asctime)s - %(name)s - %(lineno)d - %(levelname)s -  %(message)s', "%Y-%m-%d %H:%M:%S"),
    4: logging.Formatter('%(asctime)s - %(name)s - %(lineno)d - %(levelname)s -  %(message)s', "%Y-%m-%d %H:%M:%S"),
    5: logging.Formatter('%(asctime)s - %(name)s - %(lineno)d - %(levelname)s -  %(message)s', "%Y-%m-%d %H:%M:%S"),
}


class LogLevelException(Exception):
    def __init__(self, log_level):
        err = '设置的日志级别是 {0}， 设置错误，请设置为1 2 3 4 5 范围的数字'.format(log_level)
        Exception.__init__(self, err)


class Log(object):
    """
    一个日志类，用于创建和捕获日志，支持将日志打印到控制台打印和写入日志文件。
    """

    def __init__(self, logger_name=None, log_level_int=1, is_add_stream_handler=True, log_path=None, log_filename=None):
        """
        :param logger_name: 日志名称，当为None时候打印所有日志
        :param log_level_int: 日志级别，设置为 1 2 3 4 5，分别对应DEBUG，INFO，WARNING，ERROR,CRITICAL
        :param is_add_stream_handler: 是否打印日志到控制台
        :param log_path: 设置存放日志的文件夹路径
        :param log_filename: 日志的名字，仅当log_path和log_filename都不为None时候才写入到日志文件。
        :type logger_name :str
        :type log_level_int :int
        :type is_add_stream_handler :bool
        :type log_path :str
        :type log_filename :str
        """
        self.logger = logging.getLogger(logger_name)
        self.__check_log_level(log_level_int)
        self._logger_level = self.__transform_logger_level(log_level_int)
        self._is_add_stream_handler = is_add_stream_handler
        self._log_path = log_path
        self._log_filename = log_filename
        self._formatter = format_dict[log_level_int]
        self.__set_logger_level()
        self.__add_handlers()

    def debug(self, msg):
        self.logger.debug(msg)

    def info(self, msg):
        self.logger.info(msg)

    def warning(self, msg):
        self.logger.warning(msg)

    def error(self, msg):
        self.logger.error(msg)

    def critical(self, msg):
        self.logger.critical(msg)

    def __set_logger_level(self):
        self.logger.setLevel(self._logger_level)

    @staticmethod
    def __check_log_level(log_level_int):
        if log_level_int not in [1, 2, 3, 4, 5]:
            raise LogLevelException(log_level_int)

    @staticmethod
    def __transform_logger_level(log_level_int):
        logger_level = None
        if log_level_int == 1:
            logger_level = logging.DEBUG
        elif log_level_int == 2:
            logger_level = logging.INFO
        elif log_level_int == 3:
            logger_level = logging.WARNING
        elif log_level_int == 4:
            logger_level = logging.ERROR
        elif log_level_int == 5:
            logger_level = logging.CRITICAL
        return logger_level

    def __add_handlers(self):
        if self._is_add_stream_handler:
            self.__add_stream_handler()
        if all([self._log_path, self._log_filename]):
            self.__add_file_handler()

    def __add_stream_handler(self):
        """
        日志显示到控制台
        """
        stream_handler = logging.StreamHandler()
        stream_handler.setLevel(self._logger_level)
        stream_handler.setFormatter(self._formatter)
        self.logger.addHandler(stream_handler)

    def __add_file_handler(self):
        """
        日志写入日志文件
        """
        if not os.path.exists(self._log_path):
            os.makedirs(self._log_path)
        log_file = os.path.join(self._log_path, self._log_filename)
        os_name = os.name
        print os_name
        rotate_file_handler = None
        if os_name == 'nt':
            # windows下用这个，非进程安全
            rotate_file_handler = RotatingFileHandler(log_file, mode="a", maxBytes=10 * 1024 * 1024, backupCount=10, encoding="utf-8")
        if os_name == 'posix':
            # linux下可以使用ConcurrentRotatingFileHandler，进程安全的日志方式
            rotate_file_handler = ConcurrentRotatingFileHandler(log_file, mode="a", maxBytes=10 * 1024 * 1024, backupCount=10, encoding="utf-8")
        rotate_file_handler.setLevel(logging.DEBUG)
        rotate_file_handler.setFormatter(self._formatter)
        self.logger.addHandler(rotate_file_handler)


def test_func():
    """测试日志打印，单独运行test_func函数是不会打印出这条日志，没有添加handler"""
    logger = logging.getLogger('test')
    logger.info(u'需要被打印的日志')


if __name__ == "__main__":
    test_log = Log('test', 1, log_path='./logs', log_filename='test.log')
    test_func()
    test_log.info(u'添加一条日志')

    import requests

    request_log = Log('urllib3.connectionpool', 1)  # 测试三方包的日志
    resp = requests.get('https://www.baidu.com')

场景：将不同的日志写入到不同的文件，分析业务问题，查看三方包的日志。

 有的三方包的日志是必须捕获，例如concurrent包的日志，线程池运行错误都是通过日志的方式报错，如果不对日志进行打印捕获，很多语法错误或者流程错误都看不到，可能会以为写的东西没毛病呢。