S.Lott S.Lott - 2 months ago 13
Python Question

Naming Python loggers

In Django, I've got loggers all over the place, currently with hard-coded names.

For module-level logging (i.e., in a module of view functions) I have the urge to do this.

log = logging.getLogger(__name__)


For class-level logging (i.e., in a class
__init__
method) I have the urge to do this.

self.log = logging.getLogger("%s.%s" % (
self.__module__, self.__class__.__name__))


I'm looking for second opinions before I tackle several dozen occurrences of
getLogger("hard.coded.name")
.

Will this work? Anyone else naming their loggers with the same unimaginative ways?

Further, should I break down and write a class decorator for this log definition?

Answer

I typically don't use or find a need for class-level loggers, but I keep my modules at a few classes at most. A simple:

import logging
LOG = logging.getLogger(__name__)

At the top of the module and subsequent:

LOG.info('Spam and eggs are tasty!')

from anywhere in the file typically gets me to where I want to be. This avoids the need for self.log all over the place, which tends to bother me from both a put-it-in-every-class perspective and makes me 5 characters closer to 79 character lines that fit.

You could always use a pseudo-class-decorator:

>>> import logging
>>> class Foo(object):
...     def __init__(self):
...             self.log.info('Meh')
... 
>>> def logged_class(cls):
...     cls.log = logging.getLogger('{0}.{1}'.format(__name__, cls.__name__))
... 
>>> logged_class(Foo)
>>> logging.basicConfig(level=logging.DEBUG)
>>> f = Foo()
INFO:__main__.Foo:Meh