def test_executes_only_after_final_transaction_committed(self):
with transaction.atomic():
with transaction.atomic():
self.do(1)
self.assertNotified([])
self.assertNotified([])
self.assertDone([1])
def test_hooks_cleared_after_successful_commit(self):
with transaction.atomic():
self.do(1)
with transaction.atomic():
self.do(2)
self.assertDone([1, 2]) # not [1, 1, 2]
def test_implicit_savepoint_rollback(self):
"""MySQL implicitly rolls back savepoints when it deadlocks (#22291)."""
Reporter.objects.create(id=1)
Reporter.objects.create(id=2)
main_thread_ready = threading.Event()
def other_thread():
try:
with transaction.atomic():
Reporter.objects.select_for_update().get(id=1)
main_thread_ready.wait()
# 1) This line locks... (see below for 2)
Reporter.objects.exclude(id=1).update(id=2)
finally:
# This is the thread-local connection, not the main connection.
connection.close()
other_thread = threading.Thread(target=other_thread)
other_thread.start()
with self.assertRaisesMessage(OperationalError, 'Deadlock found'):
# Double atomic to enter a transaction and create a savepoint.
with transaction.atomic():
with transaction.atomic():
Reporter.objects.select_for_update().get(id=2)
main_thread_ready.set()
# The two threads can't be synchronized with an event here
# because the other thread locks. Sleep for a little while.
time.sleep(1)
# 2) ... and this line deadlocks. (see above for 1)
Reporter.objects.exclude(id=2).update(id=1)
other_thread.join()
def test_merged_rollback_commit(self):
with self.assertRaisesMessage(Exception, "Oops"):
with transaction.atomic():
Reporter.objects.create(last_name="Tintin")
with transaction.atomic(savepoint=False):
Reporter.objects.create(last_name="Haddock")
raise Exception("Oops, that's his first name")
self.assertQuerysetEqual(Reporter.objects.all(), [])
def test_wrap_callable_instance(self):
"""#20028 -- Atomic must support wrapping callable instances."""
class Callable:
def __call__(self):
pass
# Must not raise an exception
transaction.atomic(Callable())
def test_runs_hooks_in_order_registered(self):
with transaction.atomic():
self.do(1)
with transaction.atomic():
self.do(2)
self.do(3)
self.assertDone([1, 2, 3])
def test_merged_commit_rollback(self):
with transaction.atomic():
Reporter.objects.create(first_name="Tintin")
with self.assertRaisesMessage(Exception, "Oops"):
with transaction.atomic(savepoint=False):
Reporter.objects.create(first_name="Haddock")
raise Exception("Oops, that's his last name")
# Writes in the outer block are rolled back too.
self.assertQuerysetEqual(Reporter.objects.all(), [])
def test_nested_commit_commit(self):
with transaction.atomic():
Reporter.objects.create(first_name="Tintin")
with transaction.atomic():
Reporter.objects.create(first_name="Archibald",
last_name="Haddock")
self.assertQuerysetEqual(
Reporter.objects.all(),
['<Reporter: Archibald Haddock>', '<Reporter: Tintin>'])
def test_nested_commit_rollback(self):
with transaction.atomic():
Reporter.objects.create(first_name="Tintin")
with self.assertRaisesMessage(Exception, "Oops"):
with transaction.atomic():
Reporter.objects.create(first_name="Haddock")
raise Exception("Oops, that's his last name")
self.assertQuerysetEqual(Reporter.objects.all(),
['<Reporter: Tintin>'])
def test_no_savepoints_atomic_merged_with_outer(self):
with transaction.atomic():
with transaction.atomic():
self.do(1)
try:
with transaction.atomic(savepoint=False):
raise ForcedError()
except ForcedError:
pass
self.assertDone([])
def test_inner_savepoint_does_not_affect_outer(self):
with transaction.atomic():
with transaction.atomic():
self.do(1)
try:
with transaction.atomic():
raise ForcedError()
except ForcedError:
pass
self.assertDone([1])
def test_error_in_hook_doesnt_prevent_clearing_hooks(self):
try:
with transaction.atomic():
transaction.on_commit(lambda: self.notify('error'))
except ForcedError:
pass
with transaction.atomic():
self.do(1)
self.assertDone([1])
def test_hooks_cleared_on_reconnect(self):
with transaction.atomic():
self.do(1)
connection.close()
connection.connect()
with transaction.atomic():
self.do(2)
self.assertDone([2])
def test_no_hooks_run_from_failed_transaction(self):
"""If outer transaction fails, no hooks from within it run."""
try:
with transaction.atomic():
with transaction.atomic():
self.do(1)
raise ForcedError()
except ForcedError:
pass
self.assertDone([])
def test_inner_savepoint_rolled_back_with_outer(self):
with transaction.atomic():
try:
with transaction.atomic():
with transaction.atomic():
self.do(1)
raise ForcedError()
except ForcedError:
pass
self.do(2)
self.assertDone([2])
def test_hooks_cleared_after_rollback(self):
try:
with transaction.atomic():
self.do(1)
raise ForcedError()
except ForcedError:
pass
with transaction.atomic():
self.do(2)
self.assertDone([2])
def add(self, *objs, bulk=True):
self._remove_prefetched_objects()
db = router.db_for_write(self.model, instance=self.instance)
def check_and_update_obj(obj):
if not isinstance(obj, self.model):
raise TypeError("'%s' instance expected, got %r" %
(self.model._meta.object_name, obj))
setattr(obj, self.content_type_field_name, self.content_type)
setattr(obj, self.object_id_field_name, self.pk_val)
if bulk:
pks = []
for obj in objs:
if obj._state.adding or obj._state.db != db:
raise ValueError(
"%r instance isn't saved. Use bulk=False or save "
"the object first." % obj)
check_and_update_obj(obj)
pks.append(obj.pk)
self.model._base_manager.using(db).filter(pk__in=pks).update(
**{
self.content_type_field_name: self.content_type,
self.object_id_field_name: self.pk_val,
})
else:
with transaction.atomic(using=db, savepoint=False):
for obj in objs:
check_and_update_obj(obj)
obj.save()
def test_db_query_in_hook(self):
with transaction.atomic():
Thing.objects.create(num=1)
transaction.on_commit(
lambda: [self.notify(t.num) for t in Thing.objects.all()])
self.assertDone([1])
def _enter_atomics(cls):
"""Open atomic blocks for multiple databases."""
atomics = {}
for db_name in cls._databases_names():
atomics[db_name] = transaction.atomic(using=db_name)
atomics[db_name].__enter__()
return atomics
def test_add(self):
# Create an Article via the Reporter object.
new_article = self.r.article_set.create(headline="John's second story", pub_date=datetime.date(2005, 7, 29))
self.assertEqual(repr(new_article), "<Article: John's second story>")
self.assertEqual(new_article.reporter.id, self.r.id)
# Create a new article, and add it to the article set.
new_article2 = Article(headline="Paul's story", pub_date=datetime.date(2006, 1, 17))
msg = "<Article: Paul's story> instance isn't saved. Use bulk=False or save the object first."
with self.assertRaisesMessage(ValueError, msg):
self.r.article_set.add(new_article2)
self.r.article_set.add(new_article2, bulk=False)
self.assertEqual(new_article2.reporter.id, self.r.id)
self.assertQuerysetEqual(
self.r.article_set.all(),
["<Article: John's second story>", "<Article: Paul's story>", "<Article: This is a test>"]
)
# Add the same article to a different article set - check that it moves.
self.r2.article_set.add(new_article2)
self.assertEqual(new_article2.reporter.id, self.r2.id)
self.assertQuerysetEqual(self.r2.article_set.all(), ["<Article: Paul's story>"])
# Adding an object of the wrong type raises TypeError.
with transaction.atomic():
with self.assertRaisesMessage(TypeError, "'Article' instance expected, got <Reporter:"):
self.r.article_set.add(self.r2)
self.assertQuerysetEqual(
self.r.article_set.all(),
["<Article: John's second story>", "<Article: This is a test>"]
)
def _rename(self, apps, schema_editor, old_model, new_model):
ContentType = apps.get_model('contenttypes', 'ContentType')
db = schema_editor.connection.alias
if not router.allow_migrate_model(db, ContentType):
return
try:
content_type = ContentType.objects.db_manager(
db).get_by_natural_key(self.app_label, old_model)
except ContentType.DoesNotExist:
pass
else:
content_type.model = new_model
try:
with transaction.atomic(using=db):
content_type.save(update_fields={'model'})
except IntegrityError:
# Gracefully fallback if a stale content type causes a
# conflict as remove_stale_contenttypes will take care of
# asking the user what should be done next.
content_type.model = old_model
else:
# Clear the cache as the `get_by_natual_key()` call will cache
# the renamed ContentType instance by its old model name.
ContentType.objects.clear_cache()
def test_prevent_rollback(self):
with transaction.atomic():
Reporter.objects.create(first_name="Tintin")
sid = transaction.savepoint()
# trigger a database error inside an inner atomic without savepoint
with self.assertRaises(DatabaseError):
with transaction.atomic(savepoint=False):
with connection.cursor() as cursor:
cursor.execute(
"SELECT no_such_col FROM transactions_reporter")
# prevent atomic from rolling back since we're recovering manually
self.assertTrue(transaction.get_rollback())
transaction.set_rollback(False)
transaction.savepoint_rollback(sid)
self.assertQuerysetEqual(Reporter.objects.all(),
['<Reporter: Tintin>'])
def test_postgres_options(self):
qs = Tag.objects.filter(name='test')
test_options = [
{
'COSTS': False,
'BUFFERS': True,
'ANALYZE': True
},
{
'costs': False,
'buffers': True,
'analyze': True
},
{
'verbose': True,
'timing': True,
'analyze': True
},
{
'verbose': False,
'timing': False,
'analyze': True
},
]
if connection.pg_version >= 100000:
test_options.append({'summary': True})
for options in test_options:
with self.subTest(**options), transaction.atomic():
with CaptureQueriesContext(connection) as captured_queries:
qs.explain(format='text', **options)
self.assertEqual(len(captured_queries), 1)
for name, value in options.items():
option = '{} {}'.format(name.upper(),
'true' if value else 'false')
self.assertIn(option, captured_queries[0]['sql'])
def test_force_rollback(self):
with transaction.atomic():
Reporter.objects.create(first_name="Tintin")
# atomic block shouldn't rollback, but force it.
self.assertFalse(transaction.get_rollback())
transaction.set_rollback(True)
self.assertQuerysetEqual(Reporter.objects.all(), [])
def delete(self):
# sort instance collections
for model, instances in self.data.items():
self.data[model] = sorted(instances, key=attrgetter("pk"))
# if possible, bring the models in an order suitable for databases that
# don't support transactions or cannot defer constraint checks until the
# end of a transaction.
self.sort()
# number of objects deleted for each model label
deleted_counter = Counter()
with transaction.atomic(using=self.using, savepoint=False):
# send pre_delete signals
for model, obj in self.instances_with_model():
if not model._meta.auto_created:
signals.pre_delete.send(sender=model,
instance=obj,
using=self.using)
# fast deletes
for qs in self.fast_deletes:
count = qs._raw_delete(using=self.using)
deleted_counter[qs.model._meta.label] += count
# update fields
for model, instances_for_fieldvalues in self.field_updates.items():
for (field,
value), instances in instances_for_fieldvalues.items():
query = sql.UpdateQuery(model)
query.update_batch([obj.pk for obj in instances],
{field.name: value}, self.using)
# reverse instance collections
for instances in self.data.values():
instances.reverse()
# delete instances
for model, instances in self.data.items():
query = sql.DeleteQuery(model)
pk_list = [obj.pk for obj in instances]
count = query.delete_batch(pk_list, self.using)
deleted_counter[model._meta.label] += count
if not model._meta.auto_created:
for obj in instances:
signals.post_delete.send(sender=model,
instance=obj,
using=self.using)
# update collected instances
for instances_for_fieldvalues in self.field_updates.values():
for (field, value), instances in instances_for_fieldvalues.items():
for obj in instances:
setattr(obj, field.attname, value)
for model, instances in self.data.items():
for instance in instances:
setattr(instance, model._meta.pk.attname, None)
return sum(deleted_counter.values()), dict(deleted_counter)
def test_for_update_of_self_when_self_is_not_selected(self):
"""
select_for_update(of=['self']) when the only columns selected are from
related tables.
"""
with transaction.atomic():
values = list(Person.objects.select_related('born').select_for_update(of=('self',)).values('born__name'))
self.assertEqual(values, [{'born__name': self.city1.name}])
def test_unsupported_nowait_raises_error(self):
"""
NotSupportedError is raised if a SELECT...FOR UPDATE NOWAIT is run on
a database backend that supports FOR UPDATE but not NOWAIT.
"""
with self.assertRaisesMessage(NotSupportedError, 'NOWAIT is not supported on this database backend.'):
with transaction.atomic():
Person.objects.select_for_update(nowait=True).get()
def test_unsupported_skip_locked_raises_error(self):
"""
NotSupportedError is raised if a SELECT...FOR UPDATE SKIP LOCKED is run
on a database backend that supports FOR UPDATE but not SKIP LOCKED.
"""
with self.assertRaisesMessage(NotSupportedError, 'SKIP LOCKED is not supported on this database backend.'):
with transaction.atomic():
Person.objects.select_for_update(skip_locked=True).get()
def test_ordered_select_for_update(self):
"""
Subqueries should respect ordering as an ORDER BY clause may be useful
to specify a row locking order to prevent deadlocks (#27193).
"""
with transaction.atomic():
qs = Person.objects.filter(id__in=Person.objects.order_by('-id').select_for_update())
self.assertIn('ORDER BY', str(qs.query))
def test_for_update_sql_generated_skip_locked(self):
"""
The backend's FOR UPDATE SKIP LOCKED variant appears in
generated SQL when select_for_update is invoked.
"""
with transaction.atomic(), CaptureQueriesContext(connection) as ctx:
list(Person.objects.all().select_for_update(skip_locked=True))
self.assertTrue(self.has_for_update_sql(ctx.captured_queries, skip_locked=True))
