I have a UserRepository class that I am writing unittests for
class UserRepository(object):
"""
Repository that handles storage and retrieval of models.User objects
in and from the datastore.
"""
def create(self, user):
"""
Create the given user in the datastore if it doesn't exist yet.
Args:
user: The user to create.
Returns:
The created user.
Raises:
exc.DuplicateEntity: If the desired phonenumber is
already taken.
"""
duplicate_user = models.User.query(models.User.phonenumber == user.phonenumber).fetch()
if duplicate_user:
raise exc.DuplicateEntity()
user.put()
return user
I have these tests for it
class UserServiceTest(unittest.TestCase):
"""Tests for the UserService."""
def setUp(self):
"""
Called before tests are run.
"""
self.user_repo = repositories.UserRepository()
#self.policy = datastore_stub_util.PseudoRandomHRConsistencyPolicy(probability=1)
def test_create(self):
"""
Test if the create method creates a user.
"""
ndb.delete_multi(models.User.query().fetch(keys_only=True))
user = models.User(phonenumber='+31612345678#',
email='tim@castelijns.nl',
password='1234abcd')
ret_user = self.user_repo.create(user)
self.assertEqual(ret_user, user)
def test_create_duplicate_fails(self):
"""
Test if attempting to create a user with an existing phonenumber
fails.
"""
ndb.delete_multi(models.User.query().fetch(keys_only=True))
user = models.User(phonenumber='+31612345678#',
email='tim@castelijns.nl',
password='1234abcd')
self.user_repo.create(user)
with self.assertRaises(exc.DuplicateEntity):
self.user_repo.create(user)
The ndb.delete_multi(models.User.query().fetch(keys_only=True)) is to clear existing users from the test environment so test cases don't have influence on one another.
This is the custom exception
class DuplicateEntity(Exception):
"""Exception to raise when trying to create a duplicate entity."""
I run the tests with
$ nosetests --with-gae
It outputs
======================================================================
FAIL: Test if attempting to create a user with an existing phonenumber
----------------------------------------------------------------------
Traceback (most recent call last):
File "/tests/dal/test_repositories.py", line 53, in test_create_duplicate_fails
self.user_repo.create(user)
AssertionError: DuplicateEntity not raised
----------------------------------------------------------------------
Ran 2 tests in 0.080s
FAILED (failures=1)
Which is unexpected, because the 2nd call to .create here should raise the exception since there already is a user with that phonenumber.
I'm sure the code works, because I've tested it live.
What's also weird is that if I add a call to .create above the with statement, it does raise the exception:
self.user_repo.create(user)
self.user_repo.create(user)
with self.assertRaises(exc.DuplicateEntity):
self.user_repo.create(user)
So it's raised on the 3rd call, but not the 2nd.
I have a feeling it's related to the datastore consistency policy, as documented here:
The PseudoRandomHRConsistencyPolicy class lets you control the likelihood of a write applying before each global (non-ancestor) query. By setting the probability to 0%, we are instructing the datastore stub to operate with the maximum amount of eventual consistency. Maximum eventual consistency means writes will commit but always fail to apply, so global (non-ancestor) queries will consistently fail to see changes.
however I don't know how nosegae handles this. Is it even configurable? nosegae doesn't have alot of documentation.
How can I work around (or fix) this?
