def test_db_rollback(self):
"""A ballad rollback rolls back its db transaction."""
with Ballad() as ballad:
t = TestModel.objects.create(unique=1)
ballad.rollback()
self.assertEqual(0, TestModel.objects.count())
self.assertTrue(ballad.rolled_back)
def test_stanza_causes_rollback(self):
test_list = []
with Ballad() as ballad:
with ballad.stanza() as stanza:
test_list.append(0)
stanza.compensation = lambda: test_list.pop()
ballad.rollback()
self.assertEqual(0, len(test_list))
self.assertTrue(ballad.rolled_back)
def test_exception_in_block(self):
"""Exceptions in the ballad are raised normally."""
try:
with Ballad() as ballad:
raise ValueError
except ValueError:
pass
except Exception as e:
self.fail("Unexpected exception %s" % e)
self.assertTrue(ballad.rolled_back)
def test_suppress_compensation_exceptions(self):
"""Exceptions in rollback can be suppressed."""
try:
with Ballad(ignore_rollback_exceptions=True) as ballad:
ballad.compensation(lambda: unknown())
ballad.rollback()
except BalladException as e:
self.fail("BalladException was not been suppressed.")
except Exception as e:
self.fail("Unexpected exception %s" % e)
self.assertTrue(ballad.rolled_back)
def test_compensation_exception(self):
"""Exceptions in rollback get reported specially."""
try:
with Ballad() as ballad:
ballad.compensation(lambda: unknown())
ballad.rollback()
except BalladException as e:
self.assertEqual(1, len(e.exceptions))
self.assertEqual(None, e.cause)
except Exception as e:
self.fail("Unexpected exception %s" % e)
self.assertTrue(ballad.rolled_back)
def test_db_exception_causes_rollback(self):
"""An exception causes ballad rollback, which rolls back its db transaction."""
try:
with Ballad() as ballad:
t = TestModel.objects.create(unique=1)
raise ValueError
self.fail("Should have raised ValueError")
except ValueError:
pass
except:
self.fail("Raised non-ValueError")
self.assertEqual(0, TestModel.objects.count())
self.assertTrue(ballad.rolled_back)
def test_exception_in_block_and_suppressed_compensation_exceptions(self):
"""Exceptions in the ballad are raised normally."""
try:
with Ballad(ignore_rollback_exceptions=True) as ballad:
ballad.compensation(lambda: unknown())
raise ValueError
except ValueError:
pass
except BalladException as e:
self.fail("BalladException was not been suppressed.")
except Exception as e:
self.fail("Unexpected exception %s" % e)
self.assertTrue(ballad.rolled_back)
def test_exception_in_block_and_compensation_exceptions(self):
"""Exceptions in the ballad are bundled with rollback exceptions."""
try:
with Ballad() as ballad:
ballad.compensation(lambda: unknown())
raise ValueError
except BalladException as e:
self.assertEqual(1, len(e.exceptions))
self.assertEqual(3, len(e.cause))
self.assertEqual(ValueError, e.cause[0])
except ValueError:
self.fail("Unbundled ballad exception raised.")
except Exception as e:
self.fail("Unexpected exception %s" % e)
self.assertTrue(ballad.rolled_back)
def test_db_filesystem(self):
"""A ballad that isn't rolled back does not run compensating actions."""
fname = None
with Ballad() as ballad:
f = tempfile.NamedTemporaryFile(delete=False)
fname = f.name
f.write(smart_bytes("hi there"))
f.close()
ballad.compensation(lambda: os.unlink(fname))
t = TestModel.objects.create(unique=1)
self.assertTrue(os.path.exists(fname))
self.assertEqual(1, TestModel.objects.count())
os.unlink(fname)
self.assertFalse(ballad.rolled_back)
def test_db_integrity_error_rollback(self):
"""Integrity error is recovered within the ballad."""
# if commit_on_success (under Django < 1.6) or atomic (1.6+)
# didn't actually work properly, or we invoked them incorrectly
# when we wrap the context manager, we might end up with a
# non-functional database connection under postgresql (you must
# roll back after an IntegrityError).
t = TestModel.objects.create(unique=1)
try:
with Ballad() as ballad:
t = TestModel.objects.create(unique=1)
self.fail(
"Should have raised an IntegrityError out of the ballad.")
except IntegrityError as e:
pass
# test both DML and DQL to ensure we're still good
self.assertEqual(1, TestModel.objects.count())
TestModel.objects.create(unique=2)
self.assertEqual(2, TestModel.objects.count())
self.assertTrue(ballad.rolled_back)
def test_db(self):
"""A ballad that isn't rolled back commits its db transaction."""
with Ballad() as ballad:
t = TestModel.objects.create(unique=1)
self.assertEqual(1, TestModel.objects.count())
self.assertFalse(ballad.rolled_back)