class Collection(models.Model):
+ """
+ Collections are curated ordered groupings of arbitrary models.
+
+ """
+ #: :class:`CharField` with max_length 255
name = models.CharField(max_length=255)
+ #: Optional :class:`TextField`
description = models.TextField(blank=True, null=True)
@fattr(short_description='Members')
def get_count(self):
+ """Returns the number of items in the collection."""
return self.members.count()
def __unicode__(self):
use_for_related_fields = True
def with_model(self, model):
+ """
+ Given a model class or instance, returns a queryset of all instances of that model which have collection members in this manager's scope.
+
+ Example::
+
+ >>> from philo.models import Collection
+ >>> from django.contrib.auth.models import User
+ >>> collection = Collection.objects.get(name="Foo")
+ >>> collection.members.all()
+ [<CollectionMember: Foo - user1>, <CollectionMember: Foo - user2>, <CollectionMember: Foo - Spam & Eggs>]
+ >>> collection.members.with_model(User)
+ [<User: user1>, <User: user2>]
+
+ """
return model._default_manager.filter(pk__in=self.filter(member_content_type=ContentType.objects.get_for_model(model)).values_list('member_object_id', flat=True))
class CollectionMember(models.Model):
+ """
+ The collection member model represents a generic link from a :class:`Collection` to an arbitrary model instance with an attached order.
+
+ """
+ #: A :class:`CollectionMemberManager` instance
objects = CollectionMemberManager()
+ #: :class:`ForeignKey` to a :class:`Collection` instance.
collection = models.ForeignKey(Collection, related_name='members')
+ #: The numerical index of the item within the collection (optional).
index = models.PositiveIntegerField(verbose_name='Index', help_text='This will determine the ordering of the item within the collection. (Optional)', null=True, blank=True)
member_content_type = models.ForeignKey(ContentType, limit_choices_to=value_content_type_limiter, verbose_name='Member type')
member_object_id = models.PositiveIntegerField(verbose_name='Member ID')
+ #: :class:`GenericForeignKey` to an arbitrary model instance.
member = generic.GenericForeignKey('member_content_type', 'member_object_id')
def __unicode__(self):