dont add redundant handlers
[sfa.git] / 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             logfile = "/var/log/sfa.log"
22
23         if not loggername:
24             loggername=os.path.basename(logfile)
25         try:
26             handler=logging.handlers.RotatingFileHandler(logfile,maxBytes=1000000, backupCount=5) 
27         except IOError:
28             # This is usually a permissions error becaue the file is
29             # owned by root, but httpd is trying to access it.
30             tmplogfile=os.getenv("TMPDIR", "/tmp") + os.path.sep + os.path.basename(logfile)
31             handler=logging.handlers.RotatingFileHandler(tmplogfile,maxBytes=1000000, backupCount=5) 
32         handler.setFormatter(logging.Formatter("%(asctime)s - %(levelname)s - %(message)s"))
33         self.logger=logging.getLogger(loggername)
34         self.logger.setLevel(level)
35         # check if logger already has the handler we're about to add
36         handler_exists = False
37         for l_handler in self.logger.handlers:
38             if l_handler.baseFilename == handler.baseFilename and \
39                l_handler.level == handler.level:
40                 handler_exists = True 
41
42         if not handler_exists:
43             self.logger.addHandler(handler)
44             
45         self.loggername=loggername
46
47     def setLevel(self,level):
48         self.logger.setLevel(level)
49
50     # shorthand to avoid having to import logging all over the place
51     def setLevelDebug(self):
52         self.logger.setLevel(logging.DEBUG)
53
54     # define a verbose option with s/t like
55     # parser.add_option("-v", "--verbose", action="count", dest="verbose", default=0)
56     # and pass the coresponding options.verbose to this method to adjust level
57     def setLevelFromOptVerbose(self,verbose):
58         if verbose==0:
59             self.logger.setLevel(logging.WARNING)
60         elif verbose==1:
61             self.logger.setLevel(logging.INFO)
62         elif verbose==2:
63             self.logger.setLevel(logging.DEBUG)
64
65     ####################
66     def info(self, msg):
67         self.logger.info(msg)
68
69     def debug(self, msg):
70         self.logger.debug(msg)
71         
72     def warn(self, msg):
73         self.logger.warn(msg)
74    
75     def error(self, msg):
76         self.logger.error(msg)    
77  
78     def critical(self, msg):
79         self.logger.critical(msg)
80
81     # logs an exception - use in an except statement
82     def log_exc(self,message):
83         self.error("%s BEG TRACEBACK"%message+"\n"+traceback.format_exc().strip("\n"))
84         self.error("%s END TRACEBACK"%message)
85     
86     def log_exc_critical(self,message):
87         self.critical("%s BEG TRACEBACK"%message+"\n"+traceback.format_exc().strip("\n"))
88         self.critical("%s END TRACEBACK"%message)
89     
90     # for investigation purposes, can be placed anywhere
91     def log_stack(self,message):
92         to_log="".join(traceback.format_stack())
93         self.debug("%s BEG STACK"%message+"\n"+to_log)
94         self.debug("%s END STACK"%message)
95
96
97 info_logger = _SfaLogger(loggername='info', level=logging.INFO)
98 debug_logger = _SfaLogger(loggername='debug', level=logging.DEBUG)
99 warn_logger = _SfaLogger(loggername='warning', level=logging.WARNING)
100 error_logger = _SfaLogger(loggername='error', level=logging.ERROR)
101 critical_logger = _SfaLogger(loggername='critical', level=logging.CRITICAL)
102 logger = info_logger
103 sfi_logger = _SfaLogger(logfile=os.path.expanduser("~/.sfi/")+'sfi.log',loggername='sfilog', level=logging.DEBUG)
104 ########################################
105 import time
106
107 def profile(logger):
108     """
109     Prints the runtime of the specified callable. Use as a decorator, e.g.,
110     
111     @profile(logger)
112     def foo(...):
113         ...
114     """
115     def logger_profile(callable):
116         def wrapper(*args, **kwds):
117             start = time.time()
118             result = callable(*args, **kwds)
119             end = time.time()
120             args = map(str, args)
121             args += ["%s = %s" % (name, str(value)) for (name, value) in kwds.iteritems()]
122             # should probably use debug, but then debug is not always enabled
123             logger.info("PROFILED %s (%s): %.02f s" % (callable.__name__, ", ".join(args), end - start))
124             return result
125         return wrapper
126     return logger_profile
127
128
129 if __name__ == '__main__': 
130     print 'testing sfalogging into logger.log'
131     logger=_SfaLogger('logger.log')
132     logger2=_SfaLogger('logger.log', level=logging.DEBUG)
133     logger3=_SfaLogger('logger.log', level=logging.ERROR)
134     print logger.logger.handlers
135    
136     logger.critical("logger.critical")
137     logger.error("logger.error")
138     logger.warn("logger.warning")
139     logger.info("logger.info")
140     logger.debug("logger.debug")
141     logger.setLevel(logging.DEBUG)
142     logger.debug("logger.debug again")
143     
144
145     @profile(logger)
146     def sleep(seconds = 1):
147         time.sleep(seconds)
148
149     logger.info('console.info')
150     sleep(0.5)
151     logger.setLevel(logging.DEBUG)
152     sleep(0.25)
153