p31829507
/
django
mirror of https://github.com/django/django.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Fixed #24201 -- Added order_with_respect_to support to GenericForeignKey.

This commit is contained in:
Alex Hill 2015-03-27 00:52:11 +08:00 committed by Tim Graham
parent e1427cc609
commit 7bec480fe2
9 changed files with 205 additions and 63 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
django/contrib/contenttypes/fields.py
View File

@ -7,9 +7,10 @@ from django.core import checks
from django.core.exceptions import FieldDoesNotExist, ObjectDoesNotExist
from django.db import DEFAULT_DB_ALIAS, connection, models, router, transaction
from django.db.models import DO_NOTHING, signals
from django.db.models.base import ModelBase
from django.db.models.base import ModelBase, make_foreign_order_accessors
from django.db.models.fields.related import (
ForeignObject, ForeignObjectRel, ForeignRelatedObjectsDescriptor,
lazy_related_operation,
)
from django.db.models.query_utils import PathInfo
from django.utils.encoding import python_2_unicode_compatible, smart_text
@ -61,6 +62,20 @@ class GenericForeignKey(object):
setattr(cls, name, self)
def get_filter_kwargs_for_object(self, obj):
"""See corresponding method on Field"""
return {
self.fk_field: getattr(obj, self.fk_field),
self.ct_field: getattr(obj, self.ct_field),
}
def get_forward_related_filter(self, obj):
"""See corresponding method on RelatedField"""
return {
self.fk_field: obj.pk,
self.ct_field: ContentType.objects.get_for_model(obj).pk,
}
def __str__(self):
model = self.model
app = model._meta.app_label
@ -368,6 +383,21 @@ class GenericRelation(ForeignObject):
self.model = cls
setattr(cls, self.name, ReverseGenericRelatedObjectsDescriptor(self.remote_field))
# Add get_RELATED_order() and set_RELATED_order() methods if the model
# on the other end of this relation is ordered with respect to this.
def matching_gfk(field):
return (
isinstance(field, GenericForeignKey) and
self.content_type_field_name == field.ct_field and
self.object_id_field_name == field.fk_field
)
def make_generic_foreign_order_accessors(related_model, model):
if matching_gfk(model._meta.order_with_respect_to):
make_foreign_order_accessors(model, related_model)
lazy_related_operation(make_generic_foreign_order_accessors, self.model, self.remote_field.model)
def set_attributes_from_rel(self):
pass

56
django/db/models/base.py
View File

@ -311,21 +311,15 @@ class ModelBase(type):
cls.get_next_in_order = curry(cls._get_next_or_previous_in_order, is_next=True)
cls.get_previous_in_order = curry(cls._get_next_or_previous_in_order, is_next=False)
# defer creating accessors on the foreign class until we are
# certain it has been created
def make_foreign_order_accessors(cls, model, field):
setattr(
field.remote_field.model,
'get_%s_order' % cls.__name__.lower(),
curry(method_get_order, cls)
)
setattr(
field.remote_field.model,
'set_%s_order' % cls.__name__.lower(),
curry(method_set_order, cls)
)
# Defer creating accessors on the foreign class until it has been
# created and registered. If remote_field is None, we're ordering
# with respect to a GenericForeignKey and don't know what the
# foreign class is - we'll add those accessors later in
# contribute_to_class().
if opts.order_with_respect_to.remote_field:
wrt = opts.order_with_respect_to
lazy_related_operation(make_foreign_order_accessors, cls, wrt.remote_field.model, field=wrt)
remote = wrt.remote_field.model
lazy_related_operation(make_foreign_order_accessors, cls, remote)
# Give the class a docstring -- its definition.
if cls.__doc__ is None:
@ -803,8 +797,8 @@ class Model(six.with_metaclass(ModelBase)):
# If this is a model with an order_with_respect_to
# autopopulate the _order field
field = meta.order_with_respect_to
order_value = cls._base_manager.using(using).filter(
**{field.name: getattr(self, field.attname)}).count()
filter_args = field.get_filter_kwargs_for_object(self)
order_value = cls._base_manager.using(using).filter(**filter_args).count()
self._order = order_value
fields = meta.local_concrete_fields
@ -892,9 +886,8 @@ class Model(six.with_metaclass(ModelBase)):
op = 'gt' if is_next else 'lt'
order = '_order' if is_next else '-_order'
order_field = self._meta.order_with_respect_to
obj = self._default_manager.filter(**{
order_field.name: getattr(self, order_field.attname)
}).filter(**{
filter_args = order_field.get_filter_kwargs_for_object(self)
obj = self._default_manager.filter(**filter_args).filter(**{
'_order__%s' % op: self._default_manager.values('_order').filter(**{
self._meta.pk.name: self.pk
})
@ -1653,23 +1646,34 @@ class Model(six.with_metaclass(ModelBase)):
def method_set_order(ordered_obj, self, id_list, using=None):
if using is None:
using = DEFAULT_DB_ALIAS
rel_val = getattr(self, ordered_obj._meta.order_with_respect_to.remote_field.field_name)
order_name = ordered_obj._meta.order_with_respect_to.name
order_wrt = ordered_obj._meta.order_with_respect_to
filter_args = order_wrt.get_forward_related_filter(self)
# FIXME: It would be nice if there was an "update many" version of update
# for situations like this.
with transaction.atomic(using=using, savepoint=False):
for i, j in enumerate(id_list):
ordered_obj.objects.filter(**{'pk': j, order_name: rel_val}).update(_order=i)
ordered_obj.objects.filter(pk=j, **filter_args).update(_order=i)
def method_get_order(ordered_obj, self):
rel_val = getattr(self, ordered_obj._meta.order_with_respect_to.remote_field.field_name)
order_name = ordered_obj._meta.order_with_respect_to.name
order_wrt = ordered_obj._meta.order_with_respect_to
filter_args = order_wrt.get_forward_related_filter(self)
pk_name = ordered_obj._meta.pk.name
return [r[pk_name] for r in
ordered_obj.objects.filter(**{order_name: rel_val}).values(pk_name)]
return ordered_obj.objects.filter(**filter_args).values_list(pk_name, flat=True)
def make_foreign_order_accessors(model, related_model):
setattr(
related_model,
'get_%s_order' % model.__name__.lower(),
curry(method_get_order, model)
)
setattr(
related_model,
'set_%s_order' % model.__name__.lower(),
curry(method_set_order, model)
)
########
# MISC #
########

7
django/db/models/fields/__init__.py
View File

@ -678,6 +678,13 @@ class Field(RegisterLookupMixin):
setattr(cls, 'get_%s_display' % self.name,
curry(cls._get_FIELD_display, field=self))
def get_filter_kwargs_for_object(self, obj):
"""
Return a dict that when passed as kwargs to self.model.filter(), would
yield all instances having the same value for this field as obj has.
"""
return {self.name: getattr(obj, self.attname)}
def get_attname(self):
return self.name

43
django/db/models/fields/related.py
View File

@ -303,6 +303,33 @@ class RelatedField(Field):
field.do_related_class(related, model)
lazy_related_operation(resolve_related_class, cls, self.remote_field.model, field=self)
def get_forward_related_filter(self, obj):
"""
Return the keyword arguments that when supplied to
self.model.object.filter(), would select all instances related through
this field to the remote obj. This is used to build the querysets
returned by related descriptors. obj is an instance of
self.related_field.model.
"""
return {
'%s__%s' % (self.name, rh_field.name): getattr(obj, rh_field.attname)
for _, rh_field in self.related_fields
}
def get_reverse_related_filter(self, obj):
"""
Complement to get_forward_related_filter(). Return the keyword
arguments that when passed to self.related_field.model.object.filter()
select all instances of self.related_field.model related through
this field to obj. obj is an instance of self.model.
"""
base_filter = {
rh_field.attname: getattr(obj, lh_field.attname)
for lh_field, rh_field in self.related_fields
}
base_filter.update(self.get_extra_descriptor_filter(obj) or {})
return base_filter
@property
def swappable_setting(self):
"""
@ -453,11 +480,9 @@ class SingleRelatedObjectDescriptor(object):
if related_pk is None:
rel_obj = None
else:
params = {}
for lh_field, rh_field in self.related.field.related_fields:
params['%s__%s' % (self.related.field.name, rh_field.name)] = getattr(instance, rh_field.attname)
filter_args = self.related.field.get_forward_related_filter(instance)
try:
rel_obj = self.get_queryset(instance=instance).get(**params)
rel_obj = self.get_queryset(instance=instance).get(**filter_args)
except self.related.related_model.DoesNotExist:
rel_obj = None
else:
@ -603,16 +628,8 @@ class ReverseSingleRelatedObjectDescriptor(object):
if None in val:
rel_obj = None
else:
params = {
rh_field.attname: getattr(instance, lh_field.attname)
for lh_field, rh_field in self.field.related_fields}
qs = self.get_queryset(instance=instance)
extra_filter = self.field.get_extra_descriptor_filter(instance)
if isinstance(extra_filter, dict):
params.update(extra_filter)
qs = qs.filter(**params)
else:
qs = qs.filter(extra_filter, **params)
qs = qs.filter(**self.field.get_reverse_related_filter(instance))
# Assuming the database enforces foreign keys, this won't fail.
rel_obj = qs.get()
if not self.field.remote_field.multiple:

7
docs/releases/1.9.txt
View File

@ -187,6 +187,13 @@ Minor features
makes it possible to use ``REMOTE_USER`` for setups where the header is only
populated on login pages instead of every request in the session.
:mod:`django.contrib.contenttypes`
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* It's now possible to use
:attr:`~django.db.models.Options.order_with_respect_to` with a
``GenericForeignKey``.
:mod:`django.contrib.gis`
^^^^^^^^^^^^^^^^^^^^^^^^^^

39
tests/contenttypes_tests/models.py
View File

@ -1,5 +1,9 @@
from __future__ import unicode_literals
from django.contrib.contenttypes.fields import (
GenericForeignKey, GenericRelation,
)
from django.contrib.contenttypes.models import ContentType
from django.db import models
from django.utils.encoding import python_2_unicode_compatible
from django.utils.http import urlquote
@ -76,3 +80,38 @@ class FooWithBrokenAbsoluteUrl(FooWithoutUrl):
def get_absolute_url(self):
return "/users/%s/" % self.unknown_field
class Question(models.Model):
text = models.CharField(max_length=200)
answer_set = GenericRelation('Answer')
@python_2_unicode_compatible
class Answer(models.Model):
text = models.CharField(max_length=200)
content_type = models.ForeignKey(ContentType, models.CASCADE)
object_id = models.PositiveIntegerField()
question = GenericForeignKey()
class Meta:
order_with_respect_to = 'question'
def __str__(self):
return self.text
@python_2_unicode_compatible
class Post(models.Model):
"""An ordered tag on an item."""
title = models.CharField(max_length=200)
content_type = models.ForeignKey(ContentType, models.CASCADE, null=True)
object_id = models.PositiveIntegerField(null=True)
parent = GenericForeignKey()
children = GenericRelation('Post')
class Meta:
order_with_respect_to = 'parent'
def __str__(self):
return self.title

18
tests/contenttypes_tests/test_order_with_respect_to.py Normal file
View File

@ -0,0 +1,18 @@
from order_with_respect_to.tests import (
OrderWithRespectToTests, OrderWithRespectToTests2,
)
from .models import Answer, Post, Question
class OrderWithRespectToGFKTests(OrderWithRespectToTests):
Answer = Answer
Question = Question
del OrderWithRespectToTests
class OrderWithRespectToGFKTests2(OrderWithRespectToTests2):
Post = Post
del OrderWithRespectToTests2

9
tests/order_with_respect_to/models.py
View File

@ -1,5 +1,9 @@
"""
Tests for the order_with_respect_to Meta attribute.
We explicitly declare app_label on these models, because they are reused by
contenttypes_tests. When those tests are run in isolation, these models need
app_label because order_with_respect_to isn't in INSTALLED_APPS.
"""
from django.db import models
@ -10,6 +14,9 @@ from django.utils.encoding import python_2_unicode_compatible
class Question(models.Model):
text = models.CharField(max_length=200)
class Meta:
app_label = 'order_with_respect_to'
@python_2_unicode_compatible
class Answer(models.Model):
@ -18,6 +25,7 @@ class Answer(models.Model):
class Meta:
order_with_respect_to = 'question'
app_label = 'order_with_respect_to'
def __str__(self):
return six.text_type(self.text)
@ -30,6 +38,7 @@ class Post(models.Model):
class Meta:
order_with_respect_to = "parent"
app_label = 'order_with_respect_to'
def __str__(self):
return self.title

55
tests/order_with_respect_to/tests.py
View File

@ -10,13 +10,17 @@ from .models import Answer, Post, Question
class OrderWithRespectToTests(TestCase):
# Hook to allow subclasses to run these tests with alternate models.
Answer = Answer
Question = Question
@classmethod
def setUpTestData(cls):
cls.q1 = Question.objects.create(text="Which Beatle starts with the letter 'R'?")
Answer.objects.create(text="John", question=cls.q1)
Answer.objects.create(text="Paul", question=cls.q1)
Answer.objects.create(text="George", question=cls.q1)
Answer.objects.create(text="Ringo", question=cls.q1)
cls.q1 = cls.Question.objects.create(text="Which Beatle starts with the letter 'R'?")
cls.Answer.objects.create(text="John", question=cls.q1)
cls.Answer.objects.create(text="Paul", question=cls.q1)
cls.Answer.objects.create(text="George", question=cls.q1)
cls.Answer.objects.create(text="Ringo", question=cls.q1)
def test_default_to_insertion_order(self):
# Answers will always be ordered in the order they were inserted.
@ -30,30 +34,30 @@ class OrderWithRespectToTests(TestCase):
def test_previous_and_next_in_order(self):
# We can retrieve the answers related to a particular object, in the
# order they were created, once we have a particular object.
a1 = Answer.objects.filter(question=self.q1)[0]
a1 = self.q1.answer_set.all()[0]
self.assertEqual(a1.text, "John")
self.assertEqual(a1.get_next_in_order().text, "Paul")
a2 = list(Answer.objects.filter(question=self.q1))[-1]
a2 = list(self.q1.answer_set.all())[-1]
self.assertEqual(a2.text, "Ringo")
self.assertEqual(a2.get_previous_in_order().text, "George")
def test_item_ordering(self):
# We can retrieve the ordering of the queryset from a particular item.
a1 = Answer.objects.filter(question=self.q1)[1]
a1 = self.q1.answer_set.all()[1]
id_list = [o.pk for o in self.q1.answer_set.all()]
self.assertEqual(a1.question.get_answer_order(), id_list)
self.assertSequenceEqual(a1.question.get_answer_order(), id_list)
# It doesn't matter which answer we use to check the order, it will
# always be the same.
a2 = Answer.objects.create(text="Number five", question=self.q1)
self.assertEqual(
a1.question.get_answer_order(), a2.question.get_answer_order()
a2 = self.Answer.objects.create(text="Number five", question=self.q1)
self.assertListEqual(
list(a1.question.get_answer_order()), list(a2.question.get_answer_order())
)
def test_change_ordering(self):
# The ordering can be altered
a = Answer.objects.create(text="Number five", question=self.q1)
a = self.Answer.objects.create(text="Number five", question=self.q1)
# Swap the last two items in the order list
id_list = [o.pk for o in self.q1.answer_set.all()]
@ -61,7 +65,7 @@ class OrderWithRespectToTests(TestCase):
id_list.insert(-1, x)
# By default, the ordering is different from the swapped version
self.assertNotEqual(a.question.get_answer_order(), id_list)
self.assertNotEqual(list(a.question.get_answer_order()), id_list)
# Change the ordering to the swapped version -
# this changes the ordering of the queryset.
@ -76,19 +80,25 @@ class OrderWithRespectToTests(TestCase):
class OrderWithRespectToTests2(TestCase):
# Provide the Post model as a class attribute so that we can subclass this
# test case in contenttypes_tests.test_order_with_respect_to and run these
# tests with alternative implementations of Post.
Post = Post
def test_recursive_ordering(self):
p1 = Post.objects.create(title='1')
p2 = Post.objects.create(title='2')
p1_1 = Post.objects.create(title="1.1", parent=p1)
p1_2 = Post.objects.create(title="1.2", parent=p1)
Post.objects.create(title="2.1", parent=p2)
p1_3 = Post.objects.create(title="1.3", parent=p1)
self.assertEqual(p1.get_post_order(), [p1_1.pk, p1_2.pk, p1_3.pk])
p1 = self.Post.objects.create(title="1")
p2 = self.Post.objects.create(title="2")
p1_1 = self.Post.objects.create(title="1.1", parent=p1)
p1_2 = self.Post.objects.create(title="1.2", parent=p1)
self.Post.objects.create(title="2.1", parent=p2)
p1_3 = self.Post.objects.create(title="1.3", parent=p1)
self.assertSequenceEqual(p1.get_post_order(), [p1_1.pk, p1_2.pk, p1_3.pk])
def test_duplicate_order_field(self):
class Bar(models.Model):
pass
class Meta:
app_label = 'order_with_respect_to'
class Foo(models.Model):
bar = models.ForeignKey(Bar, models.CASCADE)
@ -96,6 +106,7 @@ class OrderWithRespectToTests2(TestCase):
class Meta:
order_with_respect_to = 'bar'
app_label = 'order_with_respect_to'
count = 0
for field in Foo._meta.local_fields: