Question

I’ve got a couple django models that look like this:

from django.contrib.sites.models import Site  class Photo(models.Model):     title = models.CharField(max_length=100)     site = models.ForeignKey(Site)     file = models.ImageField(upload_to=get_site_profile_path)       def __unicode__(self):         return self.title   class Gallery(models.Model):         name = models.CharField(max_length=40)     site = models.ForeignKey(Site)     photos = models.ManyToManyField(Photo, limit_choices_to = {'site':name} )          def __unicode__(self):         return self.name 

I’m having all kinds of fun trying to get the limit_choices_to working on the Gallery model. I only want the Admin to show choices for photos that belong to the same site as this gallery. Is this possible?

Answer 1

I would delete site field on my Photo model and add a ForeignKey to Gallery. I would remove limit_choices_to from photos fields on Gallery model.

Because you are using ForeignKeys to Sites, that means sites don’t share galleries and photos. Therefore having those I mentioned above is already useless.

class Photo(models.Model):     title = models.CharField(max_length=100)     gallery = models.ForeignKey(Gallery, related_name='photos')     file = models.ImageField(upload_to=get_site_profile_path)       def __unicode__(self):         return self.title   class Gallery(models.Model):         name = models.CharField(max_length=40)     site = models.ForeignKey(Site)      def __unicode__(self):         return self.name 

Once you set the site on a gallery all its photos will inherit this property. And the site will be accessible as photo_instance.gallery.site:

@property def site(self):     return self.gallery.site 

This should work as if you had a site field. But I haven’t tested it.

Things change or course, if you decide that a gallery or a photo can appear in multiple sites.