Python：logging模块-优快云博客

本文详细介绍了Python中logging模块的使用方法，包括如何设置日志级别、格式和输出文件，以及如何通过logger对象记录不同级别的日志信息。通过示例展示了如何在代码中配置logging模块，以便于开发人员更好地管理和跟踪应用程序的运行状态。


In [12]: import logging
    ...:
    ...: logging.basicConfig(level=logging.DEBUG,
    ...:                     filename='output.log',
    ...:                     datefmt='%Y/%m/%d %H:%M:%S',
    ...:                     format='%(asctime)s - %(name)s - %(levelname)s - %(lineno)d - %(module)s - %(message)s')
    ...: logger = logging.getLogger(__name__)
    ...:
    ...: logger.info('This is a log info')
    ...: logger.debug('Debugging')
    ...: logger.warning('Warning exists')
    ...: logger.info('Finish')

2019-11-04 13:00:45,976 - __main__ - INFO - This is a log info
2019-11-04 13:00:45,977 - __main__ - WARNING - Warning exists
2019-11-04 13:00:45,977 - __main__ - INFO - Finish

设置level等级，从而控制log输出的级别。

In [13]: import logging
    ...:
    ...: logging.basicConfig(level=logging.DEBUG,
    ...:                     filename='output.log',
    ...:                     datefmt='%Y/%m/%d %H:%M:%S',
    ...:                     format='%(asctime)s - %(name)s - %(levelname)s - %(lineno)d - %(module)s - %(message)s')
    ...: logger = logging.getLogger(__name__)
    ...: logger.setLevel(level=logging.DEBUG)
    ...: logger.info('This is a log info')
    ...: logger.debug('Debugging')
    ...: logger.warning('Warning exists')
    ...: logger.info('Finish')

如果不设置logger的Level的话， debug'的信息也不会被输出。

需要设置 logger.setLevel(level=logging.DEBUG)，然后信息就可以正常的显示出来了。

2019-11-04 13:10:01,634 - __main__ - INFO - This is a log info
2019-11-04 13:10:01,634 - __main__ - DEBUG - Debugging
2019-11-04 13:10:01,635 - __main__ - WARNING - Warning exists
2019-11-04 13:10:01,639 - __main__ - INFO - Finish