1 # coding:utf-8
 2 import logging  # 引入logging模块
 3
 4 # 将信息打印到控制台上
 5
 6 # 如果需要显示低于WARNING级别的内容，可以引入NOTSET级别来显示
 7 logging.basicConfig(level=logging.NOTSET)  # 设置日志级别
 8 logging.debug(u"小花")
 9 logging.info(u"如果设置了日志级别为NOTSET,那么这里可以采取debug、info的级别的内容也可以显示在控制台上了")
10
11 logging.warning(u"小丽")
12 logging.error(u"zxc")
13 logging.critical(u"qwe")
14 # 正常情况下只能看到后面三个能打印出来。因为：默认生成的root logger的level是logging.WARNING,低于该级别的就不输出了。级别排序:CRITICAL > ERROR > WARNING > INFO > DEBUG

DEBUG:root:小花
INFO:root:如果设置了日志级别为NOTSET,那么这里可以采取debug、info的级别的内容也可以显示在控制台上了
WARNING:root:小丽
ERROR:root:zxc
CRITICAL:root:qwe

 1 # coding:utf-8
 2 import logging  # 引入logging模块
 3
 4 # 通过logging.basicConfig 函数进行配置了日志级别和日志内容输出格式
 5 logging.basicConfig(level=logging.DEBUG,
 6                     format='%(asctime)s - %(filename)s[line:%(lineno)d] - %(levelname)s: %(message)s')  # logging.basicConfig函数对日志的输出格式及方式做相关配置
 7 # 因为日志基本配置中级别设置为DEBUG，所以会将DEBUG级别以上的信息都输出显示再控制台上
 8 logging.debug('this is a loggging debug message')
 9 logging.info('this is a loggging info message')
10 logging.warning('this is loggging a warning message')
11 logging.error('this is an loggging error message')
12 logging.critical('this is a loggging critical message')

2018-07-20 10:17:54,727 - logging1.py[line:8] - INFO: this is a loggging info message
2018-07-20 10:17:54,805 - logging1.py[line:9] - DEBUG: this is a loggging debug message
2018-07-20 10:17:54,805 - logging1.py[line:10] - WARNING: this is loggging a warning message
2018-07-20 10:17:54,805 - logging1.py[line:11] - ERROR: this is an loggging error message
2018-07-20 10:17:54,805 - logging1.py[line:12] - CRITICAL: this is a loggging critical message

 1 # coding:utf-8
 2 import logging  # 引入logging模块
 3 import time
 4
 5 # 第一步，创建一个logger
 6 logger = logging.getLogger()   # 获取logger实例，如果参数为空，则返回root logger，即默认的logger名称是root
 7 logger.setLevel(logging.INFO)  # Log等级总开关. logger.setLevel()设置日志级别
 8
 9 # 第二步，创建一个handler，用于写入日志文件
10 rq = time.strftime('%Y%m%d%H%M', time.localtime(time.time()))
11 logfile = rq + ".log"
12 fh = logging.FileHandler(logfile, mode='w')
13 fh.setLevel(logging.DEBUG)  # 输出到file的log等级的开关
14
15 # 同时输出到控制台
16 ch = logging.StreamHandler()
17 ch.setLevel(logging.WARNING)
18
19 # 第三步，定义handler的输出格式
20 # 配置日志的格式
21 formatter = logging.Formatter("%(asctime)s - %(filename)s[line:%(lineno)d] - %(levelname)s: %(message)s")
22 fh.setFormatter(formatter)  # 设置Formatter
23 ch.setFormatter(formatter)
24
25 # 第四步，将logger添加到handler里面
26 logger.addHandler(fh)  # 添加一个Handler
27 logger.addHandler(ch)
28
29 # 使用logger.XX来记录错误,这里的"error"可以根据所需要的级别进行修改
30 try:
31     open('/path/to/does/not/exist', 'rb')
32 except (SystemExit, KeyboardInterrupt):
33     raise
34 except Exception as e:
35     logger.error('Failed to open file', exc_info=False)  # 如果要求日志上报错误，可以将exc_info设置为True.
36
37 # # 日志
38 # logger.debug('this is a logger debug message')
39 # logger.info('this is a logger info message')
40 # logger.warning('this is a logger warning message')
41 # logger.error('this is a logger error message')
42 # logger.critical('this is a logger critical message')

2018-07-20 10:45:11,936 - logging1.py[line:35] - ERROR: Failed to open file  # 文件和控制台上是一致的