Fixed #3906 -- Fixed the reverse_m2m_name for a generic relation. Refs #2749.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6900 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Malcolm Tredinnick 2007-12-09 07:12:07 +00:00
parent 25f548a852
commit 5ed205bc8a
2 changed files with 38 additions and 34 deletions

View File

@ -16,18 +16,18 @@ class GenericForeignKey(object):
Provides a generic relation to any object through content-type/object-id
fields.
"""
def __init__(self, ct_field="content_type", fk_field="object_id"):
self.ct_field = ct_field
self.fk_field = fk_field
def contribute_to_class(self, cls, name):
# Make sure the fields exist (these raise FieldDoesNotExist,
# Make sure the fields exist (these raise FieldDoesNotExist,
# which is a fine error to raise here)
self.name = name
self.model = cls
self.cache_attr = "_%s_cache" % name
# For some reason I don't totally understand, using weakrefs here doesn't work.
dispatcher.connect(self.instance_pre_init, signal=signals.pre_init, sender=cls, weak=False)
@ -35,18 +35,18 @@ class GenericForeignKey(object):
setattr(cls, name, self)
def instance_pre_init(self, signal, sender, args, kwargs):
# Handle initalizing an object with the generic FK instaed of
# content-type/object-id fields.
# Handle initalizing an object with the generic FK instaed of
# content-type/object-id fields.
if self.name in kwargs:
value = kwargs.pop(self.name)
kwargs[self.ct_field] = self.get_content_type(value)
kwargs[self.fk_field] = value._get_pk_val()
def get_content_type(self, obj):
# Convenience function using get_model avoids a circular import when using this model
ContentType = get_model("contenttypes", "contenttype")
return ContentType.objects.get_for_model(obj)
def __get__(self, instance, instance_type=None):
if instance is None:
raise AttributeError, u"%s must be accessed via instance" % self.name
@ -77,21 +77,21 @@ class GenericForeignKey(object):
setattr(instance, self.ct_field, ct)
setattr(instance, self.fk_field, fk)
setattr(instance, self.cache_attr, value)
class GenericRelation(RelatedField, Field):
"""Provides an accessor to generic related objects (i.e. comments)"""
def __init__(self, to, **kwargs):
kwargs['verbose_name'] = kwargs.get('verbose_name', None)
kwargs['rel'] = GenericRel(to,
kwargs['rel'] = GenericRel(to,
related_name=kwargs.pop('related_name', None),
limit_choices_to=kwargs.pop('limit_choices_to', None),
symmetrical=kwargs.pop('symmetrical', True))
# Override content-type/object-id field names on the related class
self.object_id_field_name = kwargs.pop("object_id_field", "object_id")
self.content_type_field_name = kwargs.pop("content_type_field", "content_type")
self.content_type_field_name = kwargs.pop("content_type_field", "content_type")
kwargs['blank'] = True
kwargs['editable'] = False
kwargs['serialize'] = False
@ -116,9 +116,9 @@ class GenericRelation(RelatedField, Field):
def m2m_column_name(self):
return self.object_id_field_name
def m2m_reverse_name(self):
return self.object_id_field_name
return self.model._meta.pk.column
def contribute_to_class(self, cls, name):
super(GenericRelation, self).contribute_to_class(cls, name)
@ -131,13 +131,13 @@ class GenericRelation(RelatedField, Field):
def contribute_to_related_class(self, cls, related):
pass
def set_attributes_from_rel(self):
pass
def get_internal_type(self):
return "ManyToManyField"
class ReverseGenericRelatedObjectsDescriptor(object):
"""
This class provides the functionality that makes the related-object
@ -193,12 +193,12 @@ def create_generic_related_manager(superclass):
Factory function for a manager that subclasses 'superclass' (which is a
Manager) and adds behavior for generic related objects.
"""
class GenericRelatedObjectManager(superclass):
def __init__(self, model=None, core_filters=None, instance=None, symmetrical=None,
join_table=None, source_col_name=None, target_col_name=None, content_type=None,
content_type_field_name=None, object_id_field_name=None):
super(GenericRelatedObjectManager, self).__init__()
self.core_filters = core_filters or {}
self.model = model
@ -212,10 +212,10 @@ def create_generic_related_manager(superclass):
self.content_type_field_name = content_type_field_name
self.object_id_field_name = object_id_field_name
self.pk_val = self.instance._get_pk_val()
def get_query_set(self):
query = {
'%s__pk' % self.content_type_field_name : self.content_type.id,
'%s__pk' % self.content_type_field_name : self.content_type.id,
'%s__exact' % self.object_id_field_name : self.pk_val,
}
return superclass.get_query_set(self).filter(**query)

View File

@ -18,42 +18,42 @@ class TaggedItem(models.Model):
tag = models.SlugField()
content_type = models.ForeignKey(ContentType)
object_id = models.PositiveIntegerField()
content_object = generic.GenericForeignKey()
class Meta:
ordering = ["tag"]
def __unicode__(self):
return self.tag
class Animal(models.Model):
common_name = models.CharField(max_length=150)
latin_name = models.CharField(max_length=150)
tags = generic.GenericRelation(TaggedItem)
def __unicode__(self):
return self.common_name
class Vegetable(models.Model):
name = models.CharField(max_length=150)
is_yucky = models.BooleanField(default=True)
tags = generic.GenericRelation(TaggedItem)
def __unicode__(self):
return self.name
class Mineral(models.Model):
name = models.CharField(max_length=150)
hardness = models.PositiveSmallIntegerField()
# note the lack of an explicit GenericRelation here...
def __unicode__(self):
return self.name
__test__ = {'API_TESTS':"""
# Create the world in 7 lines of code...
>>> lion = Animal(common_name="Lion", latin_name="Panthera leo")
@ -117,13 +117,13 @@ __test__ = {'API_TESTS':"""
>>> [(t.tag, t.content_type, t.object_id) for t in TaggedItem.objects.all()]
[(u'clearish', <ContentType: mineral>, 1), (u'fatty', <ContentType: vegetable>, 2), (u'salty', <ContentType: vegetable>, 2), (u'shiny', <ContentType: animal>, 2)]
# If Generic Relation is not explicitly defined, any related objects
# If Generic Relation is not explicitly defined, any related objects
# remain after deletion of the source object.
>>> quartz.delete()
>>> [(t.tag, t.content_type, t.object_id) for t in TaggedItem.objects.all()]
[(u'clearish', <ContentType: mineral>, 1), (u'fatty', <ContentType: vegetable>, 2), (u'salty', <ContentType: vegetable>, 2), (u'shiny', <ContentType: animal>, 2)]
# If you delete a tag, the objects using the tag are unaffected
# If you delete a tag, the objects using the tag are unaffected
# (other than losing a tag)
>>> tag = TaggedItem.objects.get(id=1)
>>> tag.delete()
@ -132,4 +132,8 @@ __test__ = {'API_TESTS':"""
>>> [(t.tag, t.content_type, t.object_id) for t in TaggedItem.objects.all()]
[(u'clearish', <ContentType: mineral>, 1), (u'salty', <ContentType: vegetable>, 2), (u'shiny', <ContentType: animal>, 2)]
>>> ctype = ContentType.objects.get_for_model(lion)
>>> Animal.objects.filter(tags__content_type=ctype)
[<Animal: Platypus>]
"""}