--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/contrib/contenttypes/views.py	Tue Oct 14 16:00:59 2008 +0000
@@ -0,0 +1,67 @@
+from django import http
+from django.contrib.contenttypes.models import ContentType
+from django.contrib.sites.models import Site
+from django.core.exceptions import ObjectDoesNotExist
+
+def shortcut(request, content_type_id, object_id):
+    "Redirect to an object's page based on a content-type ID and an object ID."
+    # Look up the object, making sure it's got a get_absolute_url() function.
+    try:
+        content_type = ContentType.objects.get(pk=content_type_id)
+        obj = content_type.get_object_for_this_type(pk=object_id)
+    except ObjectDoesNotExist:
+        raise http.Http404("Content type %s object %s doesn't exist" % (content_type_id, object_id))
+    try:
+        absurl = obj.get_absolute_url()
+    except AttributeError:
+        raise http.Http404("%s objects don't have get_absolute_url() methods" % content_type.name)
+
+    # Try to figure out the object's domain, so we can do a cross-site redirect
+    # if necessary.
+
+    # If the object actually defines a domain, we're done.
+    if absurl.startswith('http://') or absurl.startswith('https://'):
+        return http.HttpResponseRedirect(absurl)
+
+    # Otherwise, we need to introspect the object's relationships for a
+    # relation to the Site object
+    object_domain = None
+    opts = obj._meta
+
+    # First, look for an many-to-many relationship to Site.
+    for field in opts.many_to_many:
+        if field.rel.to is Site:
+            try:
+                # Caveat: In the case of multiple related Sites, this just
+                # selects the *first* one, which is arbitrary.
+                object_domain = getattr(obj, field.name).all()[0].domain
+            except IndexError:
+                pass
+            if object_domain is not None:
+                break
+
+    # Next, look for a many-to-one relationship to Site.
+    if object_domain is None:
+        for field in obj._meta.fields:
+            if field.rel and field.rel.to is Site:
+                try:
+                    object_domain = getattr(obj, field.name).domain
+                except Site.DoesNotExist:
+                    pass
+                if object_domain is not None:
+                    break
+
+    # Fall back to the current site (if possible).
+    if object_domain is None:
+        try:
+            object_domain = Site.objects.get_current().domain
+        except Site.DoesNotExist:
+            pass
+
+    # If all that malarkey found an object domain, use it. Otherwise, fall back
+    # to whatever get_absolute_url() returned.
+    if object_domain is not None:
+        protocol = request.is_secure() and 'https' or 'http'
+        return http.HttpResponseRedirect('%s://%s%s' % (protocol, object_domain, absurl))
+    else:
+        return http.HttpResponseRedirect(absurl)