How to log messages _only once_ from all modules ?

Ron Barak rbarakx at gmail.com
Tue Nov 24 15:07:49 CET 2009


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't enlighten 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

$




More information about the Python-list mailing list