Django decorate 3rd party app's views

decorators.py

# -*- coding: utf-8 -*-

from django.conf.urls import include


def decorated_include(urls, decorator)
    """Used to decorate all urls in a 3rd party app with a specific decorator"""
    urls_to_decorate = include(urls)
    for url_pattern in urls_to_decorate
        url_pattern._callback = decorator(url_pattern._callback)

urls.py

# -*- coding: utf-8 -*-

from django.conf.urls import patterns, include, url
from django.contrib.auth.decorators import login_required

from .decorators import decorated_include

urlpatterns = patterns('',
    url(r'^admin/', decorated_include('mongoanut.urls', login_required),
    url(r'^auth/', include('social_auth.urls')),
)

Just to make sure I understand what's going on (read: ignore me if I'm wrong)

• Iterates through an app's urls
• for each url object in the pattern, decorate it's callback
• the callback is a view
• therefore, all the views are decorated at runtime

Upsides:

• Since it's only for reusable apps that you can't edit, you're only going to example this code from the top (your url's) anyway, so it's not that confusing
• Only 5% evil, no need to shower after
• It took me 15 seconds to read it and determine what's going on

Downsides:

• You use a private Django method. The risk is the devs feel free to change those on a whim without telling anyone. But as long as you're not doing that all over the place, the odds of it burning you in a major way are pretty low.

I think it's the most elegant, least intrusive solution to the problem I've seen. My only concerns are...

1. Is a circular import possible .importing urls and decorated_include from each other?
2. I'm still not sure why it was url_pattern.callback in my testing, but url_pattern._callback in yours. If .callback works, I think it would be better.

I'm working on a Django 1.6.5 site and this is what worked for me:

def decorated_include(urls, decorator):
    """Used to decorate all urls in a 3rd party app with a specific decorator"""
    urls_to_decorate = include(urls)
    for url_pattern in urls_to_decorate[0].urlpatterns:
        url_pattern._callback = decorator(url_pattern._callback)
    return urls_to_decorate

This code seems to not cover the case where a URL pattern contains a RegexURLResolver rather than a RegexURLPattern (i.e., an nested include() call in the examined include() call). This is my solution around that:

from django.conf.urls import include


def process_url_patterns(patterns, *decorators):
    """ Recursively look through patterns for views and apply decorators """
    for url_pattern in patterns:
        if hasattr(url_pattern, 'url_patterns'):
            process_url_patterns(url_pattern.url_patterns, *decorators)
        else:
            for decorator in decorators:
                print("Decorating {} with {}".format(url_pattern, decorator))
                url_pattern.callback = decorator(url_pattern.callback)


def decorated_include(urls, *decorators):
    """
    Used to decorate all urls in a 3rd party app with specific decorators
    """
    urls_to_decorate, app_name, namespace = include(urls)
    process_url_patterns(urls_to_decorate.urlpatterns, *decorators)
    return urls_to_decorate, app_name, namespace