import logging
from logging.handlers import RotatingFileHandler

def setup_logging():
    logger=logging.getLogger()
    logger.setLevel(logging.DEBUG)

    #创建文件处理器
    handler=RotatingFileHandler('app.log',maxBytes=2000,backupCount=3)
    handler.setLevel(logging.DEBUG)

    handler2=logging.StreamHandler()
    handler2.setLevel(logging.DEBUG)

    #创建日志格式器
    formatter=logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
    handler.setFormatter(formatter)

    handler2.setFormatter(formatter)

    #添加处理器到根记录器
    logger.addHandler(handler)
    logger.addHandler(handler2)