import logging

logging.basicConfig(level=logging.DEBUG,

format='%(asctime)s  %(filename)s [line:%(lineno)d] %(levelname)s  %(message)s', #定义日志格式

datefmt='%Y-%m-%d %H:%M:%S %p', #定义asctime

filename='test.log',            #定义日志文件

filemode='a')                   #定义写入模式,'a'是追加的意思

 login():

    while True:

        try:

            name = input('Input user name:')

            password = int(input('Input password:'))   #这里故意转成整型，触发异常

            if name == 'andy' and password == 'nopasswd':

                print('logging succeed!')

        except ValueError as e:

            logging.info(e)      #这里写入日志

            break

if __name__ == '__main__':

    login()　　

[root@admin_bak shell]# python3.6  test_log.py

Input user name:asdasd

Input password:asdsad  #这是输入字符串,触发异常　　

2018-01-10 11:54:40 AM test_log.py test_log.py[line:21] DEBUG invalid literal for int() with base 10: 'asdsad'　　

import time

import logging

import logging.handlers

LOG_FILE = "ping.log"          #设置日志文件名称

logger = logging.getLogger()   #实例化logging

logger.setLevel(logging.INFO)  #设置日志级别

#添加TimedRotatingFileHandler  
#定义一秒换一次log文件的handlers
#保留3个旧log文件
fh = logging.handlers.TimedRotatingFileHandler(LOG_FILE, when='D', interval=1, backupCount=10)
#定义asctime

datefmt = '%Y-%m-%d %H:%M:%S'
#定义日志格式

format_str = '%(asctime)s %(filename)s [line:%(lineno)d] %(levelname)s %(message)s'

formatter = logging.Formatter(format_str, datefmt)

fh.setFormatter(formatter)

logger.addHandler(fh)

while True:

    time.sleep(0.1)

    logging.info("test")