Django snippets

### models.py ###

from django.contrib.contenttypes.generic import GenericForeignKey, GenericRelation
from django.contrib.contenttypes.models import ContentType
from django.conf import settings
from django.db import models

class Url(models.Model):
     content_type = models.ForeignKey(ContentType)
     object_id = models.PositiveIntegerField(db_index=True)
     content_object = GenericForeignKey()
     url_string = models.CharField(max_length=256, db_index=True)
     language = models.CharField(max_length=2, choices=settings.LANGUAGES, db_index=True)
    
     class Meta:
         unique_together = (('content_type', 'object_id'), ('url_string', 'language'))

class UrlModel(models.Model):
     urls = GenericRelation(Url)

     class Meta:
         abstract = True

     def view(self, request):
         raise NotImplementedError

### middleware.py ###

from django.utils.translation import get_language
from models import Url

class UrlMiddleware(object):
     def process_response(self, request, response):
         if not response.status_code == 404:
             return response

         try:
             url = Url.objects.get(url_string=request.path_info, language=get_language())
         except Url.DoesNotExist:
             return response

         return url.content_object.view(request)

### admin.py ###

from django.contrib.contenttypes.generic import GenericTabularInline
from django.conf import settings
from models import Url

class UrlInline(GenericTabularInline):
     model = Url
     max_num = len(settings.LANGUAGES)