django settings per application - best practice?

Question

this is somewhat related to this question
Why is django's settings object a LazyObject?

In my django project i have several applications. Each application can have its own non-trivial settings file.

proj/     proj/          settings.py     app/          settings.py          views.py 

What is the general best practice here?
should app/settings.py do

from django.conf import settings APP_SETTING= lambda: settings.getattr('APP_SETTING', 'custom_value') PROJ_SETTING= lambda: settings.PROJ_SETTING 

and then in app/views.py do

import .settings  X = settings.APP_SETTING Y = settings.PROJ_SETTING 

or should I be modifying the django lazy settings object in app/settings.py as per the django coding style?

from django.conf import settings # not even sure how I would check for a default value that was specified in proj/settings.py settings.configure(APP_SETTING='custom_value') 

and then each app/views.py just consumes proj/settings.py via django.conf settings?

from django.conf import settings X = settings.APP_SETTING Y = settings.PROJ_SETTING 

There are obviously quite a few other permutations but I think my intent is clear.
Thanks in advance.

Answer 1

The simplest solution is to use the getattr(settings, 'MY_SETTING', 'my_default') trick that you mention youself. It can become a bit tedious to have to do this in multiple places, though.

Extra recommendation: use a per-app prefix like MYAPP_MY_SETTING.

There is a django app, however, that gets rid of the getattr and that handles the prefix for you. See http://django-appconf.readthedocs.org/en/latest/

Normally you create a conf.py per app with contents like this:

from django.conf import settings from appconf import AppConf  class MyAppConf(AppConf):     SETTING_1 = "one"     SETTING_2 = (         "two",     ) 

And in your code:

from myapp.conf import settings  def my_view(request):     return settings.MYAPP_SETTINGS_1  # Note the handy prefix 

Should you need to customize the setting in your site, a regular entry in your site's settings.py is all you need to do:

MYAPP_SETTINGS_1 = "four, four I say"