Fixed #14861 -- Added an admonition about the potential for circular imports with custom logging handlers (which produces an extremely confusing error message) to the logging docs. Thanks to donspaulding for the report and adamv for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@15449 bcc190cf-cafb-0310-a4f2-bffc1f526a37
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Gabriel Hurley 2011-02-07 23:56:39 +00:00
parent f80e997c50
commit 66312066a0
1 changed files with 30 additions and 0 deletions

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@ -349,6 +349,36 @@ This logging configuration does the following things:
printed to the console; ``ERROR`` and ``CRITICAL``
messages will also be output via e-mail.
.. admonition:: Custom handlers and circular imports
If your ``settings.py`` specifies a custom handler class and the file
defining that class also imports ``settings.py`` a circular import will
occur.
For example, if ``settings.py`` contains the following config for
:setting:`LOGGING`::
LOGGING = {
'version': 1,
'handlers': {
'custom_handler': {
'level': 'INFO',
'class': 'myproject.logconfig.MyHandler',
}
}
}
and ``myproject/logconfig.py`` has the following line before the
``MyHandler`` definition::
from django.conf import settings
then the ``dictconfig`` module will raise an exception like the following::
ValueError: Unable to configure handler 'custom_handler':
Unable to configure handler 'custom_handler':
'module' object has no attribute 'logconfig'
.. _formatter documentation: http://docs.python.org/library/logging.html#formatter-objects
Custom logging configuration