What is the urls.py regex evaluation order in django?
django-urls, python, regex
Solution
Read the Django document
How Django processes a request
When a user requests a page from your Django-powered site, this is the algorithm the system follows to determine which Python code to execute:
- Django determines the root URLconf module to use. Ordinarily, this is the value of the ROOT_URLCONF setting, but if the incoming HttpRequest object has an attribute called urlconf (set by middleware request processing), its value will be used in place of the ROOT_URLCONF setting.
- Django loads that Python module and looks for the variable urlpatterns. This should be a Python list, in the format returned by the function django.conf.urls.patterns().
- Django runs through each URL pattern, in order, and stops at the first one that matches the requested URL.
- Once one of the regexes matches, Django imports and calls the given view, which is a simple Python function. The view gets passed an HttpRequest as its first argument and any values captured in the regex as remaining arguments.
- If no regex matches, or if an exception is raised during any point in this process, Django invokes an appropriate error-handling view. See Error handling below.
It said `3. Django runs through each URL pattern, in order, and stops at the first one that matches the requested URL.` So I think this is a bug.
You should add `$` in every url pattern unless `Including other URLconfs`
Problem
I was having some problems with the regex in urls.py (I am a beginner to django as well as regexes in general) Here is my original urls.py ``` url(r'^name/(?P<name>\w+)/$', 'course.views.name'), url(r'^', 'course.views.index'), ``` And I was trying to access it using this: ``` http://127.0.0.1:8000/name/blah/ ``` My view looks like: ``` def index(request): return HttpResponse("Hello, sam. You're at the course index.") def name(request, name): return HttpResponse("Hello, %s. You're at the course index." % name) ``` The result I was getting was that for no matter what input I gave, I would regularly get the "index" function, and not the "name" function. I thought the problem was with the first regex. But then, I changed the the 2nd one to: ``` url(r'^$', 'course.views.index'), ``` And THIS works just the way I figured it to work! I understand that "$" means end of line, but shouldnt the 1st regex have been evaluated first? What is the order in which these expressions are matched? Adding a "$" to every url is not that big a deal, but I would like to understand why I am putting it there. I am using Django1.4 and Python 2.7