Fixed #13432 -- Corrected the logic for router use on OneToOne fields; also... (848fbdc3) · Commits · Dom Sekotill / django

django/db/models/fields/related.py

+1 −1

Original line number	Diff line number	Diff line
		@@ -222,7 +222,7 @@ class SingleRelatedObjectDescriptor(object):
		return getattr(instance, self.cache_name)
		except AttributeError:
		params = {'%s__pk' % self.related.field.name: instance._get_pk_val()}
		db = router.db_for_read(instance.__class__, instance=instance)
		db = router.db_for_read(self.related.model, instance=instance)
		rel_obj = self.related.model._base_manager.using(db).get(**params)
		setattr(instance, self.cache_name, rel_obj)
		return rel_obj

tests/regressiontests/multiple_database/models.py

+4 −1

Original line number	Diff line number	Diff line
		@@ -45,6 +45,9 @@ class Book(models.Model):
		ordering = ('title',)

		class UserProfile(models.Model):
		user = models.OneToOneField(User)
		user = models.OneToOneField(User, null=True)
		flavor = models.CharField(max_length=100)

		class Meta:
		ordering = ('flavor',)

tests/regressiontests/multiple_database/tests.py

+133 −0

Original line number	Diff line number	Diff line
		@@ -498,6 +498,115 @@ class QueryTestCase(TestCase):
		self.assertEquals(list(Book.objects.using('other').values_list('title',flat=True)),
		[u'Dive into HTML5', u'Dive into Python', u'Dive into Water'])

		def test_o2o_separation(self):
		"OneToOne fields are constrained to a single database"
		# Create a user and profile on the default database
		alice = User.objects.db_manager('default').create_user('alice', 'alice@example.com')
		alice_profile = UserProfile.objects.using('default').create(user=alice, flavor='chocolate')

		# Create a user and profile on the other database
		bob = User.objects.db_manager('other').create_user('bob', 'bob@example.com')
		bob_profile = UserProfile.objects.using('other').create(user=bob, flavor='crunchy frog')

		# Retrieve related objects; queries should be database constrained
		alice = User.objects.using('default').get(username="alice")
		self.assertEquals(alice.userprofile.flavor, "chocolate")

		bob = User.objects.using('other').get(username="bob")
		self.assertEquals(bob.userprofile.flavor, "crunchy frog")

		# Check that queries work across joins
		self.assertEquals(list(User.objects.using('default').filter(userprofile__flavor='chocolate').values_list('username', flat=True)),
		[u'alice'])
		self.assertEquals(list(User.objects.using('other').filter(userprofile__flavor='chocolate').values_list('username', flat=True)),
		[])

		self.assertEquals(list(User.objects.using('default').filter(userprofile__flavor='crunchy frog').values_list('username', flat=True)),
		[])
		self.assertEquals(list(User.objects.using('other').filter(userprofile__flavor='crunchy frog').values_list('username', flat=True)),
		[u'bob'])

		# Reget the objects to clear caches
		alice_profile = UserProfile.objects.using('default').get(flavor='chocolate')
		bob_profile = UserProfile.objects.using('other').get(flavor='crunchy frog')

		# Retrive related object by descriptor. Related objects should be database-baound
		self.assertEquals(alice_profile.user.username, 'alice')
		self.assertEquals(bob_profile.user.username, 'bob')

		def test_o2o_cross_database_protection(self):
		"Operations that involve sharing FK objects across databases raise an error"
		# Create a user and profile on the default database
		alice = User.objects.db_manager('default').create_user('alice', 'alice@example.com')

		# Create a user and profile on the other database
		bob = User.objects.db_manager('other').create_user('bob', 'bob@example.com')

		# Set a one-to-one relation with an object from a different database
		alice_profile = UserProfile.objects.using('default').create(user=alice, flavor='chocolate')
		try:
		bob.userprofile = alice_profile
		self.fail("Shouldn't be able to assign across databases")
		except ValueError:
		pass

		# BUT! if you assign a FK object when the base object hasn't
		# been saved yet, you implicitly assign the database for the
		# base object.
		bob_profile = UserProfile.objects.using('other').create(user=bob, flavor='crunchy frog')

		new_bob_profile = UserProfile(flavor="spring surprise")

		charlie = User(username='charlie',email='charlie@example.com')
		charlie.set_unusable_password()

		# initially, no db assigned
		self.assertEquals(new_bob_profile._state.db, None)
		self.assertEquals(charlie._state.db, None)

		# old object comes from 'other', so the new object is set to use 'other'...
		new_bob_profile.user = bob
		charlie.userprofile = bob_profile
		self.assertEquals(new_bob_profile._state.db, 'other')
		self.assertEquals(charlie._state.db, 'other')

		# ... but it isn't saved yet
		self.assertEquals(list(User.objects.using('other').values_list('username',flat=True)),
		[u'bob'])
		self.assertEquals(list(UserProfile.objects.using('other').values_list('flavor',flat=True)),
		[u'crunchy frog'])

		# When saved (no using required), new objects goes to 'other'
		charlie.save()
		bob_profile.save()
		new_bob_profile.save()
		self.assertEquals(list(User.objects.using('default').values_list('username',flat=True)),
		[u'alice'])
		self.assertEquals(list(User.objects.using('other').values_list('username',flat=True)),
		[u'bob', u'charlie'])
		self.assertEquals(list(UserProfile.objects.using('default').values_list('flavor',flat=True)),
		[u'chocolate'])
		self.assertEquals(list(UserProfile.objects.using('other').values_list('flavor',flat=True)),
		[u'crunchy frog', u'spring surprise'])

		# This also works if you assign the O2O relation in the constructor
		denise = User.objects.db_manager('other').create_user('denise','denise@example.com')
		denise_profile = UserProfile(flavor="tofu", user=denise)

		self.assertEquals(denise_profile._state.db, 'other')
		# ... but it isn't saved yet
		self.assertEquals(list(UserProfile.objects.using('default').values_list('flavor',flat=True)),
		[u'chocolate'])
		self.assertEquals(list(UserProfile.objects.using('other').values_list('flavor',flat=True)),
		[u'crunchy frog', u'spring surprise'])

		# When saved, the new profile goes to 'other'
		denise_profile.save()
		self.assertEquals(list(UserProfile.objects.using('default').values_list('flavor',flat=True)),
		[u'chocolate'])
		self.assertEquals(list(UserProfile.objects.using('other').values_list('flavor',flat=True)),
		[u'crunchy frog', u'spring surprise', u'tofu'])

		def test_generic_key_separation(self):
		"Generic fields are constrained to a single database"
		# Create a book and author on the default database
		@@ -1103,6 +1212,30 @@ class RouterTestCase(TestCase):
		bob, created = dive.authors.get_or_create(name='Bob')
		self.assertEquals(bob._state.db, 'default')

		def test_o2o_cross_database_protection(self):
		"Operations that involve sharing FK objects across databases raise an error"
		# Create a user and profile on the default database
		alice = User.objects.db_manager('default').create_user('alice', 'alice@example.com')

		# Create a user and profile on the other database
		bob = User.objects.db_manager('other').create_user('bob', 'bob@example.com')

		# Set a one-to-one relation with an object from a different database
		alice_profile = UserProfile.objects.create(user=alice, flavor='chocolate')
		try:
		bob.userprofile = alice_profile
		except ValueError:
		self.fail("Assignment across master/slave databases with a common source should be ok")

		# Database assignments of original objects haven't changed...
		self.assertEquals(alice._state.db, 'default')
		self.assertEquals(alice_profile._state.db, 'default')
		self.assertEquals(bob._state.db, 'other')

		# ... but they will when the affected object is saved.
		bob.save()
		self.assertEquals(bob._state.db, 'default')

		def test_generic_key_cross_database_protection(self):
		"Generic Key operations can span databases if they share a source"
		# Create a book and author on the default database