Python中的logging日志模块

import os,sys,logging
from logging import handlers


class Loggers(object):

    # 日志级别关系映射
    level_relations = {
        'debug': logging.DEBUG, 'info': logging.INFO, 'warning': logging.WARNING,
        'error': logging.ERROR, 'critical': logging.CRITICAL
    }

    def __init__(self,filename='test.log',when='D',backCount=30,level='info', log_dir='log',
                 fmt='%(asctime)s - %(filename)s[line:%(lineno)d] - %(levelname)s: %(message)s'):
        if not os.path.exists(log_dir):
            os.makedirs(log_dir)

        self.logger = logging.getLogger(filename)
        self.log_name = os.path.join(log_dir,filename)
        format_str = logging.Formatter(fmt)  # 设置日志格式
        self.logger.setLevel(self.level_relations.get(level))  # 设置日志级别
        file_handler = handlers.TimedRotatingFileHandler(filename=self.log_name,when=when,backupCount=backCount,encoding='utf-8')
        stream_handler = logging.StreamHandler()  # 往屏幕上输出
        stream_handler.setFormatter(format_str)   # 往屏幕上输出
        file_handler.setFormatter(format_str)
        self.logger.addHandler(file_handler)
        self.logger.addHandler(stream_handler)    # 往屏幕上输出