本文实例讲述了python实现的系统实用log类。分享给大家供大家参考。具体如下：

每个系统都必不可少会需要一个log类，方便了解系统的运行状况和排错，python本身已经提供了一个logger了，很强大，只要稍微封装一下就可以放到自己的系统了，下面是我自己的log类

文件名：logger.py

\"\"\"This module takes care of the logging
logger helps in creating a logging system for the application 
Logging is initialised by function LoggerInit.
\"\"\"
import logging
import os
import sys
class logger(object):
  \"\"\"Class provides methods to perform logging.\"\"\"
  m_logger = None
  def __init__(self, opts, logfile):
    \"\"\"Set the default logging path.\"\"\"
    self.opts = opts
    self.myname = \'dxscs\'
    self.logdir = \'.\'
    self.logfile = logfile
    self.filename = os.path.join(self.logdir, self.logfile)
  def loginit(self):
    \"\"\"Calls function LoggerInit to start initialising the logging system.\"\"\"
    logdir = os.path.normpath(os.path.expanduser(self.logdir))
    self.logfilename = os.path.normpath(os.path.expanduser(self.filename))
    if not os.path.isdir(logdir):
      try:
        os.mkdir(logdir)
      except OSError, e:
        msg = (\'(%s)\'%e)
        print msg
        sys.exit(1)
    self.logger_init(self.myname)
  def logger_init(self, loggername):
    \"\"\"Initialise the logging system.
    This includes logging to console and a file. By default, console prints
    messages of level WARN and above and file prints level INFO and above.
    In DEBUG mode (-D command line option) prints messages of level DEBUG
    and above to both console and file.
    Args:
     loggername: String - Name of the application printed along with the log
     message.
    \"\"\"
    fileformat = \'[%(asctime)s] %(name)s: [%(filename)s: %(lineno)d]: %(levelname)-8s: %(message)s\'
    logger.m_logger = logging.getLogger(loggername)
    logger.m_logger.setLevel(logging.INFO)
    self.console = logging.StreamHandler()
    self.console.setLevel(logging.CRITICAL)
    consformat = logging.Formatter(fileformat)
    self.console.setFormatter(consformat)
    self.filelog = logging.FileHandler(filename=self.logfilename, mode=\'w+\')
    self.filelog.setLevel(logging.INFO)
    self.filelog.setFormatter(consformat)
    logger.m_logger.addHandler(self.filelog)
    logger.m_logger.addHandler(self.console)
    if self.opts[\'debug\'] == True:
      self.console.setLevel(logging.DEBUG)
      self.filelog.setLevel(logging.DEBUG)
      logger.m_logger.setLevel(logging.DEBUG)
    if not self.opts[\'nofork\']:
      self.console.setLevel(logging.WARN)
  def logstop(self):
    \"\"\"Shutdown logging process.\"\"\"
    logging.shutdown()
#test    
if __name__ == \'__main__\':
  #debug mode & not in daemon
  opts = {\'debug\':True,\'nofork\':True}
  log = logger(opts, \'dxscs_source.log\')
  log.loginit()
  log.m_logger.info(\'hello,world\')

执行结果：

终端和文件中都显示有：[2012-09-06 16:56:01,498] dxscs: [logger.py: 88]: INFO    : hello,world

如果只需要显示在文件中可以将debug和nofork选项都置为false

希望本文所述对大家的Python程序设计有所帮助。