import datetime import pickle from django.db import models from django.test import TestCase from django.utils.version import get_version from .models import Container, Event, Group, Happening, M2MModel class PickleabilityTestCase(TestCase): @classmethod def setUpTestData(cls): Happening.objects.create() # make sure the defaults are working (#20158) def assert_pickles(self, qs): self.assertEqual(list(pickle.loads(pickle.dumps(qs))), list(qs)) def test_related_field(self): g = Group.objects.create(name="Ponies Who Own Maybachs") self.assert_pickles(Event.objects.filter(group=g.id)) def test_datetime_callable_default_all(self): self.assert_pickles(Happening.objects.all()) def test_datetime_callable_default_filter(self): self.assert_pickles(Happening.objects.filter(when=datetime.datetime.now())) def test_string_as_default(self): self.assert_pickles(Happening.objects.filter(name="test")) def test_standalone_method_as_default(self): self.assert_pickles(Happening.objects.filter(number1=1)) def test_staticmethod_as_default(self): self.assert_pickles(Happening.objects.filter(number2=1)) def test_filter_reverse_fk(self): self.assert_pickles(Group.objects.filter(event=1)) def test_doesnotexist_exception(self): # Ticket #17776 original = Event.DoesNotExist("Doesn't exist") unpickled = pickle.loads(pickle.dumps(original)) # Exceptions are not equal to equivalent instances of themselves, so # can't just use assertEqual(original, unpickled) self.assertEqual(original.__class__, unpickled.__class__) self.assertEqual(original.args, unpickled.args) def test_doesnotexist_class(self): klass = Event.DoesNotExist self.assertIs(pickle.loads(pickle.dumps(klass)), klass) def test_multipleobjectsreturned_class(self): klass = Event.MultipleObjectsReturned self.assertIs(pickle.loads(pickle.dumps(klass)), klass) def test_forward_relatedobjectdoesnotexist_class(self): # ForwardManyToOneDescriptor klass = Event.group.RelatedObjectDoesNotExist self.assertIs(pickle.loads(pickle.dumps(klass)), klass) # ForwardOneToOneDescriptor klass = Happening.event.RelatedObjectDoesNotExist self.assertIs(pickle.loads(pickle.dumps(klass)), klass) def test_reverse_one_to_one_relatedobjectdoesnotexist_class(self): klass = Event.happening.RelatedObjectDoesNotExist self.assertIs(pickle.loads(pickle.dumps(klass)), klass) def test_manager_pickle(self): pickle.loads(pickle.dumps(Happening.objects)) def test_model_pickle(self): """ A model not defined on module level is picklable. """ original = Container.SomeModel(pk=1) dumped = pickle.dumps(original) reloaded = pickle.loads(dumped) self.assertEqual(original, reloaded) # Also, deferred dynamic model works Container.SomeModel.objects.create(somefield=1) original = Container.SomeModel.objects.defer('somefield')[0] dumped = pickle.dumps(original) reloaded = pickle.loads(dumped) self.assertEqual(original, reloaded) self.assertEqual(original.somefield, reloaded.somefield) def test_model_pickle_m2m(self): """ Test intentionally the automatically created through model. """ m1 = M2MModel.objects.create() g1 = Group.objects.create(name='foof') m1.groups.add(g1) m2m_through = M2MModel._meta.get_field('groups').remote_field.through original = m2m_through.objects.get() dumped = pickle.dumps(original) reloaded = pickle.loads(dumped) self.assertEqual(original, reloaded) def test_model_pickle_dynamic(self): class Meta: proxy = True dynclass = type("DynamicEventSubclass", (Event,), {'Meta': Meta, '__module__': Event.__module__}) original = dynclass(pk=1) dumped = pickle.dumps(original) reloaded = pickle.loads(dumped) self.assertEqual(original, reloaded) self.assertIs(reloaded.__class__, dynclass) def test_specialized_queryset(self): self.assert_pickles(Happening.objects.values('name')) self.assert_pickles(Happening.objects.values('name').dates('when', 'year')) # With related field (#14515) self.assert_pickles( Event.objects.select_related('group').order_by('title').values_list('title', 'group__name') ) def test_pickle_prefetch_related_idempotence(self): g = Group.objects.create(name='foo') groups = Group.objects.prefetch_related('event_set') # First pickling groups = pickle.loads(pickle.dumps(groups)) self.assertSequenceEqual(groups, [g]) # Second pickling groups = pickle.loads(pickle.dumps(groups)) self.assertSequenceEqual(groups, [g]) def test_pickle_prefetch_queryset_usable_outside_of_prefetch(self): # Prefetch shouldn't affect the fetch-on-pickle behavior of the # queryset passed to it. Group.objects.create(name='foo') events = Event.objects.order_by('id') Group.objects.prefetch_related(models.Prefetch('event_set', queryset=events)) with self.assertNumQueries(1): events2 = pickle.loads(pickle.dumps(events)) with self.assertNumQueries(0): list(events2) def test_pickle_prefetch_queryset_still_usable(self): g = Group.objects.create(name='foo') groups = Group.objects.prefetch_related( models.Prefetch('event_set', queryset=Event.objects.order_by('id')) ) groups2 = pickle.loads(pickle.dumps(groups)) self.assertSequenceEqual(groups2.filter(id__gte=0), [g]) def test_pickle_prefetch_queryset_not_evaluated(self): Group.objects.create(name='foo') groups = Group.objects.prefetch_related( models.Prefetch('event_set', queryset=Event.objects.order_by('id')) ) list(groups) # evaluate QuerySet with self.assertNumQueries(0): pickle.loads(pickle.dumps(groups)) def test_pickle_prefetch_related_with_m2m_and_objects_deletion(self): """ #24831 -- Cached properties on ManyToOneRel created in QuerySet.delete() caused subsequent QuerySet pickling to fail. """ g = Group.objects.create(name='foo') m2m = M2MModel.objects.create() m2m.groups.add(g) Group.objects.all().delete() m2ms = M2MModel.objects.prefetch_related('groups') m2ms = pickle.loads(pickle.dumps(m2ms)) self.assertSequenceEqual(m2ms, [m2m]) def test_annotation_with_callable_default(self): # Happening.when has a callable default of datetime.datetime.now. qs = Happening.objects.annotate(latest_time=models.Max('when')) self.assert_pickles(qs) def test_missing_django_version_unpickling(self): """ #21430 -- Verifies a warning is raised for querysets that are unpickled without a Django version """ qs = Group.missing_django_version_objects.all() msg = "Pickled queryset instance's Django version is not specified." with self.assertRaisesMessage(RuntimeWarning, msg): pickle.loads(pickle.dumps(qs)) def test_unsupported_unpickle(self): """ #21430 -- Verifies a warning is raised for querysets that are unpickled with a different Django version than the current """ qs = Group.previous_django_version_objects.all() msg = "Pickled queryset instance's Django version 1.0 does not match the current version %s." % get_version() with self.assertRaisesMessage(RuntimeWarning, msg): pickle.loads(pickle.dumps(qs)) class InLookupTests(TestCase): @classmethod def setUpTestData(cls): for i in range(1, 3): group = Group.objects.create(name='Group {}'.format(i)) cls.e1 = Event.objects.create(title='Event 1', group=group) def test_in_lookup_queryset_evaluation(self): """ Neither pickling nor unpickling a QuerySet.query with an __in=inner_qs lookup should evaluate inner_qs. """ events = Event.objects.filter(group__in=Group.objects.all()) with self.assertNumQueries(0): dumped = pickle.dumps(events.query) with self.assertNumQueries(0): reloaded = pickle.loads(dumped) reloaded_events = Event.objects.none() reloaded_events.query = reloaded self.assertSequenceEqual(reloaded_events, [self.e1]) def test_in_lookup_query_evaluation(self): events = Event.objects.filter(group__in=Group.objects.values('id').query) with self.assertNumQueries(0): dumped = pickle.dumps(events.query) with self.assertNumQueries(0): reloaded = pickle.loads(dumped) reloaded_events = Event.objects.none() reloaded_events.query = reloaded self.assertSequenceEqual(reloaded_events, [self.e1])