[1.9.x] Fixed #25563 -- Cached deferred models in their proxied model's _meta.apps. (522b0bc9) · Commits · Dom Sekotill / django

django/db/models/query_utils.py

+5 −4

Original line number	Diff line number	Diff line
		@@ -10,7 +10,6 @@ from __future__ import unicode_literals
		import inspect
		from collections import namedtuple

		from django.apps import apps
		from django.core.exceptions import FieldDoesNotExist
		from django.db.backends import utils
		from django.db.models.constants import LOOKUP_SEP
		@@ -272,12 +271,13 @@ def deferred_class_factory(model, attrs):
		"""
		if not attrs:
		return model
		opts = model._meta
		# Never create deferred models based on deferred model
		if model._deferred:
		# Deferred models are proxies for the non-deferred model. We never
		# create chains of defers => proxy_for_model is the non-deferred
		# model.
		model = model._meta.proxy_for_model
		model = opts.proxy_for_model
		# The app registry wants a unique name for each model, otherwise the new
		# class won't be created (we get an exception). Therefore, we generate
		# the name using the passed in attrs. It's OK to reuse an existing class
		@@ -286,13 +286,14 @@ def deferred_class_factory(model, attrs):
		name = utils.truncate_name(name, 80, 32)

		try:
		return apps.get_model(model._meta.app_label, name)
		return opts.apps.get_model(model._meta.app_label, name)

		except LookupError:

		class Meta:
		proxy = True
		app_label = model._meta.app_label
		apps = opts.apps
		app_label = opts.app_label

		overrides = {attr: DeferredAttribute(attr, model) for attr in attrs}
		overrides["Meta"] = Meta

+9 −0

Original line number	Diff line number	Diff line
		@@ -25,3 +25,12 @@ Bugfixes
		* Allowed filtering over a ``RawSQL`` annotation (:ticket:`25506`).

		* Made the ``Concat`` database function idempotent on SQLite (:ticket:`25517`).

		* Avoided a confusing stack trace when starting :djadmin:`runserver` with an
		invalid :setting:`INSTALLED_APPS` setting (:ticket:`25510`). This regression
		appeared in 1.8.5 as a side effect of fixing :ticket:`24704`.

		* Made deferred models use their proxied model's ``_meta.apps`` for caching
		and retrieval (:ticket:`25563`). This prevents any models generated in data
		migrations using ``QuerySet.defer()`` from leaking to test and application
		code.

+20 −0

Original line number	Diff line number	Diff line
		@@ -3,8 +3,10 @@ from __future__ import unicode_literals
		from operator import attrgetter

		from django.apps import apps
		from django.apps.registry import Apps
		from django.contrib.contenttypes.models import ContentType
		from django.contrib.sessions.backends.db import SessionStore
		from django.db import models
		from django.db.models import Count
		from django.db.models.query_utils import (
		DeferredAttribute, deferred_class_factory,
		@@ -263,6 +265,24 @@ class DeferRegressionTest(TestCase):
		deferred_cls = deferred_class_factory(Item, ())
		self.assertFalse(deferred_cls._deferred)

		def test_deferred_class_factory_apps_reuse(self):
		"""
		#25563 - model._meta.apps should be used for caching and
		retrieval of the created proxy class.
		"""
		isolated_apps = Apps(['defer_regress'])

		class BaseModel(models.Model):
		field = models.BooleanField()

		class Meta:
		apps = isolated_apps
		app_label = 'defer_regress'

		deferred_model = deferred_class_factory(BaseModel, ['field'])
		self.assertIs(deferred_model._meta.apps, isolated_apps)
		self.assertIs(deferred_class_factory(BaseModel, ['field']), deferred_model)


		class DeferAnnotateSelectRelatedTest(TestCase):
		def test_defer_annotate_select_related(self):