How to log messages _only once_ from all modules ?
Ron Barak
rbarakx at gmail.com
Tue Nov 24 10:14:56 EST 2009
On Nov 24, 5:08 pm, Soltys <sol... at noabuse.com> wrote:
> Ron Barak pisze:
>
>
>
>
>
> > On Nov 24, 3:45 pm, Soltys <sol... at noabuse.com> wrote:
> >> Barak, Ron pisze:
>
> >>> Hi,
> >>> I'm trying to add the logging module to my application, but I seem to be missing something.
> >>> My application (a wxPython one) has a main script that calls various helper classes.
> >>> I want the log messages from all modules to go to one central log file.
> >>> When I implement logging, I think that due to preparation, I get the same message more than once.
> >>> Here's an example:
> >>> $ cat -n server.py
> >>> 1 import logging
> >>> 2 import logging.handlers
> >>> 3
> >>> 4 class Server():
> >>> 5 def __init__(self):
> >>> 6 self.client_logger = logging.getLogger("client")
> >>> 7 self.client_logger.setLevel(logging.DEBUG)
> >>> 8 h = logging.FileHandler("client.log")
> >>> 9 h.setLevel(logging.DEBUG)
> >>> 10 formatter = logging.Formatter("%(asctime)s %(name)-12s %(levelname)-8s %(message)s")
> >>> 11 h.setFormatter(formatter)
> >>> 12 self.client_logger.addHandler(h)
> >>> 13
> >>> 14 def util(self):
> >>> 15 self.client_logger.warning('This message comes from Server module')
> >>> $ cat -n client.py
> >>> 1 import logging
> >>> 2 import logging.handlers
> >>> 3 from server import Server
> >>> 4
> >>> 5 class Client():
> >>> 6 def __init__(self):
> >>> 7 self.client_logger = logging.getLogger("client")
> >>> 8 self.client_logger.setLevel(logging.DEBUG)
> >>> 9 h = logging.FileHandler("client.log")
> >>> 10 h.setLevel(logging.DEBUG)
> >>> 11 formatter = logging.Formatter("%(asctime)s %(name)-12s %(levelname)-8s %(message)s")
> >>> 12 h.setFormatter(formatter)
> >>> 13 self.client_logger.addHandler(h)
> >>> 14
> >>> 15 def client_test(self):
> >>> 16 self.client_logger.warning("This message comes from Client module")
> >>> 17
> >>> 18 if __name__ == "__main__":
> >>> 19 ser = Server()
> >>> 20 cli = Client()
> >>> 21 ser.util()
> >>> 22 cli.client_test()
> >>> $ rm client.log ; python client.py ; cat client.log
> >>> 2009-11-24 14:40:39,762 client WARNING This message comes from Server module
> >>> 2009-11-24 14:40:39,762 client WARNING This message comes from Server module
> >>> 2009-11-24 14:40:39,762 client WARNING This message comes from Client module
> >>> 2009-11-24 14:40:39,762 client WARNING This message comes from Client module
> >>> Googling and readinghttp://docs.python.org/library/logging.htmldidn'tenlighten me.
> >>> Could you suggest what should I change in the above scripts so that the log messages would appear only once ?
> >>> Thanks,
> >>> Ron.
> >> Have a look athttp://docs.python.org/library/logging.html#logger-objects
> >> First thing mentioned is Logger.propagate which is, what I believe, you're
> >> looking for ;)
>
> >> --
> >> Soltys
>
> >> "Free software is a matter of liberty not price"- Hide quoted text -
>
> >> - Show quoted text -
>
> > Hi Soltys,
> > I actually tried that, without any noticeable effects, viz.:
>
> > $ cat server.py
> > import logging
> > import logging.handlers
>
> > class Server():
> > def __init__(self):
> > self.client_logger = logging.getLogger("client")
> > self.client_logger.setLevel(logging.DEBUG)
> > h = logging.FileHandler("client.log")
> > h.setLevel(logging.DEBUG)
> > formatter = logging.Formatter("%(asctime)s %(name)-12s %
> > (levelname)-8s %(message)s")
> > h.setFormatter(formatter)
> > self.client_logger.addHandler(h)
> > self.client_logger.propagate = 0
>
> > def util(self):
> > self.client_logger.warning('This message comes from Server
> > module')
>
> > $ cat client.py
> > import logging
> > import logging.handlers
> > from server import Server
>
> > class Client():
> > def __init__(self):
> > self.client_logger = logging.getLogger("client")
> > self.client_logger.setLevel(logging.DEBUG)
> > h = logging.FileHandler("client.log")
> > h.setLevel(logging.DEBUG)
> > formatter = logging.Formatter("%(asctime)s %(name)-12s %
> > (levelname)-8s %(message)s")
> > h.setFormatter(formatter)
> > self.client_logger.addHandler(h)
> > self.client_logger.propagate = 0
>
> > def client_test(self):
> > self.client_logger.warning("This message comes from Client
> > module")
>
> > if __name__ == "__main__":
> > ser = Server()
> > cli = Client()
> > ser.util()
> > cli.client_test()
>
> > $ rm client.log ; python client.py ; cat client.log
> > 2009-11-24 16:06:35,710 client WARNING This message comes from
> > Server module
> > 2009-11-24 16:06:35,710 client WARNING This message comes from
> > Server module
> > 2009-11-24 16:06:35,710 client WARNING This message comes from
> > Client module
> > 2009-11-24 16:06:35,710 client WARNING This message comes from
> > Client module
>
> > $
>
> Rename logger in server.py to server:
> self.client_logger = logging.getLogger("server")
>
> Rerun, you should get sth. like this:
> $ cat client.log
> 2009-11-24 16:06:54,990 server WARNING This message comes from Server module
> 2009-11-24 16:06:54,990 client WARNING This message comes from Client module
>
> --
> Soltys
>
> "Free software is a matter of liberty not price"- Hide quoted text -
>
> - Show quoted text -
Many thanks Soltys, that did the trick (actually, no need for setting
propagate to 0), namely,
$ cat client.py
import logging
import logging.handlers
from server import Server
class Client():
def __init__(self):
self.client_logger = logging.getLogger("client")
self.client_logger.setLevel(logging.DEBUG)
h = logging.FileHandler("client.log")
h.setLevel(logging.DEBUG)
formatter = logging.Formatter("%(asctime)s %(name)-12s %
(levelname)-8s %(message)s")
h.setFormatter(formatter)
self.client_logger.addHandler(h)
def client_test(self):
self.client_logger.warning("This message comes from Client
module")
if __name__ == "__main__":
ser = Server()
cli = Client()
ser.util()
cli.client_test()
$ cat server.py
import logging
import logging.handlers
class Server():
def __init__(self):
self.client_logger = logging.getLogger("server")
self.client_logger.setLevel(logging.DEBUG)
h = logging.FileHandler("client.log")
h.setLevel(logging.DEBUG)
formatter = logging.Formatter("%(asctime)s %(name)-12s %
(levelname)-8s %(message)s")
h.setFormatter(formatter)
self.client_logger.addHandler(h)
def util(self):
self.client_logger.warning('This message comes from Server
module')
$ rm client.log ; python client.py ; cat client.log
2009-11-24 17:13:15,989 server WARNING This message comes from
Server module
2009-11-24 17:13:15,989 client WARNING This message comes from
Client module
More information about the Python-list
mailing list