Python: logging module

Logging module

logging module可以分成logger、handler、formatter等三大元件。

Level	When it’s used
DEBUG	Detailed information, typically of interest only when diagnosing problems.
INFO	Confirmation that things are working as expected.
WARNING	An indication that something unexpected happened, or indicative of some problem in the near future (e.g. ‘disk space low’). The software is still working as expected.
ERROR	Due to a more serious problem, the software has not been able to perform some function.
CRITICAL	A serious error, indicating that the program itself may be unable to continue running.

Level	Numeric value
CRITICAL	50
ERROR	40
WARNING	30
INFO	20
DEBUG	10
NOTSET	0

NOTEST < DEBUG < INFO < WARNING < ERROR < CRITICAL

如果把debug level設置為INFO，則<INFO的log將不會輸出，只有>= INFO的log才會輸出。

Logger.debug(msg [ ,*args [, **kwargs]])

　　记录DEBUG级别的日志信息。参数msg是信息的格式，args与kwargs分别是格式参数。

[python] view plaincopy

1. import logging  
2. logging.basicConfig(filename = os.path.join(os.getcwd(), 'log.txt'), level = logging.DEBUG)  
3. log = logging.getLogger('root')  
4. log.debug('%s, %s, %s', *('error', 'debug', 'info'))  
5. log.debug('%(module)s, %(info)s', {'module': 'log', 'info': 'error'})  

Logger.info(msg[ , *args[ , **kwargs] ] )

Logger.warnning(msg[ , *args[ , **kwargs] ] )

Logger.error(msg[ , *args[ , **kwargs] ] )

Logger.critical(msg[ , *args[ , **kwargs] ] )

　　记录相应级别的日志信息。参数的含义与Logger.debug一样。

logger.conf

qualname

he qualname entry is the hierarchical channel name of the logger, that is to say the name used by the application to get the logger.

Reference:
1. python logging module 入門, http://blog.csdn.net/jgood/article/details/4340740
2. http://www.icoding.co/2012/08/logging-html