1.简单的将日志打印到屏幕


 



import logging logging.debug('This is debug message') logging.info('This is info message') logging.warning('This is warning message')
  
 屏幕上打印:WARNING:root:This is warning message

默认情况下,logging将日志打印到屏幕,日志级别为WARNING;
日志级别大小关系为:CRITICAL > ERROR > WARNING > INFO > DEBUG > NOTSET,当然也可以自己定义日志级别。

import logging logging.basicConfig(level=logging.DEBUG,                 format='%(asctime)s %(filename)s[line:%(lineno)d] %(levelname)s %(message)s',                 datefmt='%a, %d %b %Y %H:%M:%S',                 filename='myapp.log',                 filemode='w')      logging.debug('This is debug message') logging.info('This is info message') logging.warning('This is warning message')
  
 ./myapp.log文件中内容为: Sun, 24 May 2009 21:48:54 demo2.py[line:11] DEBUG This is debug message Sun, 24 May 2009 21:48:54 demo2.py[line:12] INFO This is info message Sun, 24 May 2009 21:48:54 demo2.py[line:13] WARNING This is warning message

logging.basicConfig函数各参数:
filename: 指定日志文件名
filemode: 和file函数意义相同,指定日志文件的打开模式,'w'或'a'
format: 指定输出的格式和内容,format可以输出很多有用信息,如上例所示:
 %(levelno)s: 打印日志级别的数值
 %(levelname)s: 打印日志级别名称
 %(pathname)s: 打印当前执行程序的路径,其实就是sys.argv[0]
 %(filename)s: 打印当前执行程序名
 %(funcName)s: 打印日志的当前函数
 %(lineno)d: 打印日志的当前行号
 %(asctime)s: 打印日志的时间
 %(thread)d: 打印线程ID
 %(threadName)s: 打印线程名称
 %(process)d: 打印进程ID
 %(message)s: 打印日志信息
datefmt: 指定时间格式,同time.strftime()
level: 设置日志级别,默认为logging.WARNING
stream: 指定将日志的输出流,可以指定输出到sys.stderr,sys.stdout或者文件,默认输出到sys.stderr,当stream和filename同时指定时,stream被忽略

import logging logging.basicConfig(level=logging.DEBUG,                 format='%(asctime)s %(filename)s[line:%(lineno)d] %(levelname)s %(message)s',                 datefmt='%a, %d %b %Y %H:%M:%S',                 filename='myapp.log',                 filemode='w') ################################################################################################# #定义一个StreamHandler,将INFO级别或更高的日志信息打印到标准错误,并将其添加到当前的日志处理对象# console = logging.StreamHandler() console.setLevel(logging.INFO) formatter = logging.Formatter('%(name)-12s: %(levelname)-8s %(message)s') console.setFormatter(formatter) logging.getLogger('').addHandler(console) ################################################################################################# logging.debug('This is debug message') logging.info('This is info message') logging.warning('This is warning message')
  
 屏幕上打印: root        : INFO     This is info message root        : WARNING  This is warning message
 ./myapp.log文件中内容为:Sun, 24 May 2009 21:48:54 demo2.py[line:11] DEBUG This is debug message Sun, 24 May 2009 21:48:54 demo2.py[line:12] INFO This is info message Sun, 24 May 2009 21:48:54 demo2.py[line:13] WARNING This is warning message
import loggingfrom logging.handlers import RotatingFileHandler ################################################################################################# #定义一个RotatingFileHandler,最多备份5个日志文件,每个日志文件最大10M Rthandler = RotatingFileHandler('myapp.log', maxBytes=10*1024*1024,backupCount=5) Rthandler.setLevel(logging.INFO) formatter = logging.Formatter('%(name)-12s: %(levelname)-8s %(message)s') Rthandler.setFormatter(formatter) logging.getLogger('').addHandler(Rthandler) ################################################################################################

从上例和本例可以看出,logging有一个日志处理的主对象,其它处理方式都是通过addHandler添加进去的。
logging的几种handle方式如下:

 

logging.StreamHandler: 日志输出到流,可以是sys.stderr、sys.stdout或者文件
 logging.FileHandler: 日志输出到文件 日志回滚方式,实际使用时用RotatingFileHandler和TimedRotatingFileHandler
 logging.handlers.BaseRotatingHandler
 logging.handlers.RotatingFileHandler
 logging.handlers.TimedRotatingFileHandler logging.handlers.SocketHandler: 远程输出日志到TCP/IP sockets
 logging.handlers.DatagramHandler:  远程输出日志到UDP sockets
 logging.handlers.SMTPHandler:  远程输出日志到邮件地址
 logging.handlers.SysLogHandler: 日志输出到syslog
 logging.handlers.NTEventLogHandler: 远程输出日志到Windows NT/2000/XP的事件日志
 logging.handlers.MemoryHandler: 日志输出到内存中的制定buffer
 logging.handlers.HTTPHandler: 通过"GET"或"POST"远程输出到HTTP服务器

 

由于StreamHandler和FileHandler是常用的日志处理方式,所以直接包含在logging模块中,而其他方式则包含在logging.handlers模块中,
上述其它处理方式的使用请参见python2.5手册!

#logger.conf
 ###############################################
 [loggers]keys=root,example01,example02
 [logger_root]level=DEBUG handlers=hand01,hand02
 [logger_example01]handlers=hand01,hand02 qualname=example01 propagate=0
 [logger_example02]handlers=hand01,hand03 qualname=example02 propagate=0
 ###############################################
 [handlers]keys=hand01,hand02,hand03
 [handler_hand01]class=StreamHandler level=INFO formatter=form02 args=(sys.stderr,)
 [handler_hand02]class=FileHandler level=DEBUG formatter=form01 args=('myapp.log', 'a')
 [handler_hand03]class=handlers.RotatingFileHandler level=INFO formatter=form02 args=('myapp.log', 'a', 10*1024*1024, 5)
 ###############################################
 [formatters]keys=form01,form02
 [formatter_form01]format=%(asctime)s %(filename)s[line:%(lineno)d] %(levelname)s %(message)s datefmt=%a, %d %b %Y %H:%M:%S
 [formatter_form02]format=%(name)-12s: %(levelname)-8s %(message)s datefmt=

上例3:

import loggingimport logging.config logging.config.fileConfig("logger.conf") logger = logging.getLogger("example01") logger.debug('This is debug message') logger.info('This is info message') logger.warning('This is warning message')

上例4:

import loggingimport logging.config logging.config.fileConfig("logger.conf") logger = logging.getLogger("example02") logger.debug('This is debug message') logger.info('This is info message') logger.warning('This is warning message')