python/lib/django_1_4/django/contrib/contenttypes/views.py

   1 from django import http
   2 from django.contrib.contenttypes.models import ContentType
   3 from django.contrib.sites.models import Site, get_current_site
   4 from django.core.exceptions import ObjectDoesNotExist
   5 from django.utils.translation import ugettext as _
   6
   7 def shortcut(request, content_type_id, object_id):
   8     """
   9     Redirect to an object's page based on a content-type ID and an object ID.
  10     """
  11     # Look up the object, making sure it's got a get_absolute_url() function.
  12     try:
  13         content_type = ContentType.objects.get(pk=content_type_id)
  14         if not content_type.model_class():
  15             raise http.Http404(_(u"Content type %(ct_id)s object has no associated model") %
  16                                {'ct_id': content_type_id})
  17         obj = content_type.get_object_for_this_type(pk=object_id)
  18     except (ObjectDoesNotExist, ValueError):
  19         raise http.Http404(_(u"Content type %(ct_id)s object %(obj_id)s doesn't exist") %
  20                            {'ct_id': content_type_id, 'obj_id': object_id})
  21
  22     try:
  23         get_absolute_url = obj.get_absolute_url
  24     except AttributeError:
  25         raise http.Http404(_("%(ct_name)s objects don't have a get_absolute_url() method") %
  26                            {'ct_name': content_type.name})
  27     absurl = get_absolute_url()
  28
  29     # Try to figure out the object's domain, so we can do a cross-site redirect
  30     # if necessary.
  31
  32     # If the object actually defines a domain, we're done.
  33     if absurl.startswith('http://') or absurl.startswith('https://'):
  34         return http.HttpResponseRedirect(absurl)
  35
  36     # Otherwise, we need to introspect the object's relationships for a
  37     # relation to the Site object
  38     object_domain = None
  39
  40     if Site._meta.installed:
  41         opts = obj._meta
  42
  43         # First, look for an many-to-many relationship to Site.
  44         for field in opts.many_to_many:
  45             if field.rel.to is Site:
  46                 try:
  47                     # Caveat: In the case of multiple related Sites, this just
  48                     # selects the *first* one, which is arbitrary.
  49                     object_domain = getattr(obj, field.name).all()[0].domain
  50                 except IndexError:
  51                     pass
  52                 if object_domain is not None:
  53                     break
  54
  55         # Next, look for a many-to-one relationship to Site.
  56         if object_domain is None:
  57             for field in obj._meta.fields:
  58                 if field.rel and field.rel.to is Site:
  59                     try:
  60                         object_domain = getattr(obj, field.name).domain
  61                     except Site.DoesNotExist:
  62                         pass
  63                     if object_domain is not None:
  64                         break
  65
  66     # Fall back to the current site (if possible).
  67     if object_domain is None:
  68         try:
  69             object_domain = get_current_site(request).domain
  70         except Site.DoesNotExist:
  71             pass
  72
  73     # If all that malarkey found an object domain, use it. Otherwise, fall back
  74     # to whatever get_absolute_url() returned.
  75     if object_domain is not None:
  76         protocol = request.is_secure() and 'https' or 'http'
  77         return http.HttpResponseRedirect('%s://%s%s'
  78                                          % (protocol, object_domain, absurl))
  79     else:
  80         return http.HttpResponseRedirect(absurl)