Django urlconf sometimes failing? - django

Question

I've got a django urls.py file like so:
Base file:
urlpatterns = patterns('',
(r'^', include('sp.sp_app.urls')),
(r'^', include('sp.sp_api_activity.urls')),
(r'^', include('sp.sp_api_player.urls')),
(r'^', include('sp.sp_web.urls')),
)
In the sp.sp_web.urls file, I have the following:
from django.conf.urls.defaults import *
urlpatterns = patterns('superproof.superproof_web.views',
(r'^$','index'), #Shows your home page
(r'^challenge$','spcreatechallenge'),
(r'^player/`$','getlastactivity'),
(r'^yearlysummary/','yearlysummary'),
(r'^processchallenge$','processchallenge'),
(r'^activity/(\w{32})$','activitydetail'),
)
The yearlysummary url is loading sometimes. Other times, I get a 404 error. This happens with the exact same valid URL. I don't change anything in the URL, or in the code.
When I get the 404 error with debug turned on, my yearlysummary URL pattern isn't on the list.
Any ideas?

Answer 1

A couple things I noticed that could be an issue...
I notice you are not namespacing your included urls for each app. Not knowing what the other urls modules look like, I can assume its possible that you can have colliding urls. I Would recommend doing something like this:
urlpatterns = patterns('',
(r'', include('sp.sp_app.urls')),
(r'^activity/', include('sp.sp_api_activity.urls')),
(r'^player/', include('sp.sp_api_player.urls')),
(r'^web/', include('sp.sp_web.urls')),
)
Normally when you have url includes, they are for different apps, so you would want to namespace them to avoid two apps specifying the same url pattern.
Also, whats that back-tick in one of your urls? Did you mean to expect that?
(r'^player/`$','getlastactivity'),

Answer 2

jdi is spot on, on the analysis. I'll try to explain why exactly is there the issue, in your case.
You will notice that if you include (r'^', include('sp.sp_web.urls') as the first pattern in the main urls.py, your view will rightly load always.
When you have it as the last pattern, the reason it doesn't match the other times is that, that pattern is matching some other pattern in the earlier pattern, say [/w+]. The debug page, on a 404 of the url pattern, displays all the sub-url patterns of one of the patterns it matches. This is exactly why the pattern isn't on the urls displayed on the debug page.
Like jdi mentions it is a good practice to namespace the urls properly, so this doesn't occur. You can probably do it even without namespacing, but your regexes have to be proper, with the end character $ included, at least.