sfa/util/sfalogging.py

   1 #!/usr/bin/python
   2
   3 import os, sys
   4 import traceback
   5 import logging, logging.handlers
   6
   7 CRITICAL=logging.CRITICAL
   8 ERROR=logging.ERROR
   9 WARNING=logging.WARNING
  10 INFO=logging.INFO
  11 DEBUG=logging.DEBUG
  12
  13 # a logger that can handle tracebacks
  14 class _SfaLogger:
  15     def __init__ (self,logfile=None,loggername=None,level=logging.INFO):
  16         # default is to locate loggername from the logfile if avail.
  17         if not logfile:
  18             loggername='console'
  19             handler=logging.StreamHandler()
  20             handler.setFormatter(logging.Formatter("%(levelname)s %(message)s"))
  21         else:
  22             if not loggername:
  23                 loggername=os.path.basename(logfile)
  24             try:
  25                 handler=logging.handlers.RotatingFileHandler(logfile,maxBytes=1000000, backupCount=5)
  26             except IOError:
  27                 # This is usually a permissions error becaue the file is
  28                 # owned by root, but httpd is trying to access it.
  29                 tmplogfile=os.getenv("TMPDIR", "/tmp") + os.path.sep + os.path.basename(logfile)
  30                 handler=logging.handlers.RotatingFileHandler(tmplogfile,maxBytes=1000000, backupCount=5)
  31             handler.setFormatter(logging.Formatter("%(asctime)s - %(levelname)s - %(message)s"))
  32
  33         self.logger=logging.getLogger(loggername)
  34         self.logger.setLevel(level)
  35         self.logger.addHandler(handler)
  36         self.loggername=loggername
  37
  38     def setLevel(self,level):
  39         self.logger.setLevel(level)
  40
  41     # shorthand to avoid having to import logging all over the place
  42     def setLevelDebug(self):
  43         self.logger.setLevel(logging.DEBUG)
  44
  45     # define a verbose option with s/t like
  46     # parser.add_option("-v", "--verbose", action="count", dest="verbose", default=0)
  47     # and pass the coresponding options.verbose to this method to adjust level
  48     def setLevelFromOptVerbose(self,verbose):
  49         if verbose==0:
  50             self.logger.setLevel(logging.WARNING)
  51         elif verbose==1:
  52             self.logger.setLevel(logging.INFO)
  53         elif verbose==2:
  54             self.logger.setLevel(logging.DEBUG)
  55
  56     ####################
  57     def info(self, msg):
  58         self.logger.info(msg)
  59
  60     def debug(self, msg):
  61         self.logger.debug(msg)
  62
  63     def warn(self, msg):
  64         self.logger.warn(msg)
  65
  66     def error(self, msg):
  67         self.logger.error(msg)
  68
  69     def critical(self, msg):
  70         self.logger.critical(msg)
  71
  72     # logs an exception - use in an except statement
  73     def log_exc(self,message):
  74         self.error("%s BEG TRACEBACK"%message+"\n"+traceback.format_exc().strip("\n"))
  75         self.error("%s END TRACEBACK"%message)
  76
  77     def log_exc_critical(self,message):
  78         self.critical("%s BEG TRACEBACK"%message+"\n"+traceback.format_exc().strip("\n"))
  79         self.critical("%s END TRACEBACK"%message)
  80
  81     # for investigation purposes, can be placed anywhere
  82     def log_stack(self,message):
  83         to_log="".join(traceback.format_stack())
  84         self.debug("%s BEG STACK"%message+"\n"+to_log)
  85         self.debug("%s END STACK"%message)
  86
  87 ####################
  88 # import-related operations go in this file
  89 _import_logger=_SfaLogger(logfile='/var/log/sfa_import.log')
  90 # servers log into /var/log/sfa.log
  91 _server_logger=_SfaLogger(logfile='/var/log/sfa.log')
  92 ## clients use the console
  93 #_console_logger=_SfaLogger()
  94
  95 # default is to use the server-side logger
  96 #_the_logger=_server_logger
  97
  98 # clients would change the default by issuing one of these call
  99 #def sfa_logger_goes_to_console():
 100 #    current_module=sys.modules[globals()['__name__']]
 101 #    current_module._the_logger=_console_logger
 102 #
 103 # clients would change the default by issuing one of these call
 104 #def sfa_logger_goes_to_import():
 105 #    current_module=sys.modules[globals()['__name__']]
 106 #    current_module._the_logger=_import_logger
 107
 108 # this is how to retrieve the 'right' logger
 109 def sfa_logger():
 110     return _server_logger
 111
 112 ########################################
 113 import time
 114
 115 def profile(logger):
 116     """
 117     Prints the runtime of the specified callable. Use as a decorator, e.g.,
 118
 119     @profile(logger)
 120     def foo(...):
 121         ...
 122     """
 123     def logger_profile(callable):
 124         def wrapper(*args, **kwds):
 125             start = time.time()
 126             result = callable(*args, **kwds)
 127             end = time.time()
 128             args = map(str, args)
 129             args += ["%s = %s" % (name, str(value)) for (name, value) in kwds.iteritems()]
 130             # should probably use debug, but then debug is not always enabled
 131             logger.info("PROFILED %s (%s): %.02f s" % (callable.__name__, ", ".join(args), end - start))
 132             return result
 133         return wrapper
 134     return logger_profile
 135
 136
 137 if __name__ == '__main__':
 138     print 'testing sfalogging into logger.log'
 139     logger=_SfaLogger('logger.log')
 140     logger.critical("logger.critical")
 141     logger.error("logger.error")
 142     logger.warning("logger.warning")
 143     logger.info("logger.info")
 144     logger.debug("logger.debug")
 145     logger.setLevel(logging.DEBUG)
 146     logger.debug("logger.debug again")
 147
 148     #sfa_logger_goes_to_console()
 149     my_logger=sfa_logger()
 150     my_logger.info("redirected to console")
 151
 152     @profile(my_logger)
 153     def sleep(seconds = 1):
 154         time.sleep(seconds)
 155
 156     my_logger.info('console.info')
 157     sleep(0.5)
 158     my_logger.setLevel(logging.DEBUG)
 159     sleep(0.25)
 160