class TestStudentModuleStorage(TestCase):
    def setUp(self):
        self.desc_md = {}
        student_module = StudentModuleFactory(
            state=json.dumps({'a_field': 'a_value'}))
        self.user = student_module.student
        self.mdc = ModelDataCache(
            [mock_descriptor([mock_field(Scope.user_state, 'a_field')])],
            course_id, self.user)
        self.kvs = LmsKeyValueStore(self.desc_md, self.mdc)

    def test_get_existing_field(self):
        "Test that getting an existing field in an existing StudentModule works"
        self.assertEquals('a_value', self.kvs.get(user_state_key('a_field')))

    def test_get_missing_field(self):
        "Test that getting a missing field from an existing StudentModule raises a KeyError"
        self.assertRaises(KeyError, self.kvs.get,
                          user_state_key('not_a_field'))

    def test_set_existing_field(self):
        "Test that setting an existing user_state field changes the value"
        self.kvs.set(user_state_key('a_field'), 'new_value')
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({'a_field': 'new_value'},
                          json.loads(StudentModule.objects.all()[0].state))

    def test_set_missing_field(self):
        "Test that setting a new user_state field changes the value"
        self.kvs.set(user_state_key('not_a_field'), 'new_value')
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({
            'a_field': 'a_value',
            'not_a_field': 'new_value'
        }, json.loads(StudentModule.objects.all()[0].state))

    def test_delete_existing_field(self):
        "Test that deleting an existing field removes it from the StudentModule"
        self.kvs.delete(user_state_key('a_field'))
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertRaises(KeyError, self.kvs.get,
                          user_state_key('not_a_field'))

    def test_delete_missing_field(self):
        "Test that deleting a missing field from an existing StudentModule raises a KeyError"
        self.assertRaises(KeyError, self.kvs.delete,
                          user_state_key('not_a_field'))
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({'a_field': 'a_value'},
                          json.loads(StudentModule.objects.all()[0].state))

    def test_has_existing_field(self):
        "Test that `has` returns True for existing fields in StudentModules"
        self.assertTrue(self.kvs.has(user_state_key('a_field')))

    def test_has_missing_field(self):
        "Test that `has` returns False for missing fields in StudentModule"
        self.assertFalse(self.kvs.has(user_state_key('not_a_field')))
示例#2
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class StorageTestBase(object):
    factory = None
    scope = None
    key_factory = None
    storage_class = None

    def setUp(self):
        field_storage = self.factory.create()
        if hasattr(field_storage, 'student'):
            self.user = field_storage.student
        else:
            self.user = UserFactory.create()
        self.desc_md = {}
        self.mdc = ModelDataCache([mock_descriptor([mock_field(self.scope, 'existing_field')])], course_id, self.user)
        self.kvs = LmsKeyValueStore(self.desc_md, self.mdc)

    def test_set_and_get_existing_field(self):
        self.kvs.set(self.key_factory('existing_field'), 'test_value')
        self.assertEquals('test_value', self.kvs.get(self.key_factory('existing_field')))

    def test_get_existing_field(self):
        "Test that getting an existing field in an existing Storage Field works"
        self.assertEquals('old_value', self.kvs.get(self.key_factory('existing_field')))

    def test_get_missing_field(self):
        "Test that getting a missing field from an existing Storage Field raises a KeyError"
        self.assertRaises(KeyError, self.kvs.get, self.key_factory('missing_field'))

    def test_set_existing_field(self):
        "Test that setting an existing field changes the value"
        self.kvs.set(self.key_factory('existing_field'), 'new_value')
        self.assertEquals(1, self.storage_class.objects.all().count())
        self.assertEquals('new_value', json.loads(self.storage_class.objects.all()[0].value))

    def test_set_missing_field(self):
        "Test that setting a new field changes the value"
        self.kvs.set(self.key_factory('missing_field'), 'new_value')
        self.assertEquals(2, self.storage_class.objects.all().count())
        self.assertEquals('old_value', json.loads(self.storage_class.objects.get(field_name='existing_field').value))
        self.assertEquals('new_value', json.loads(self.storage_class.objects.get(field_name='missing_field').value))

    def test_delete_existing_field(self):
        "Test that deleting an existing field removes it"
        self.kvs.delete(self.key_factory('existing_field'))
        self.assertEquals(0, self.storage_class.objects.all().count())

    def test_delete_missing_field(self):
        "Test that deleting a missing field from an existing Storage Field raises a KeyError"
        self.assertRaises(KeyError, self.kvs.delete, self.key_factory('missing_field'))
        self.assertEquals(1, self.storage_class.objects.all().count())

    def test_has_existing_field(self):
        "Test that `has` returns True for an existing Storage Field"
        self.assertTrue(self.kvs.has(self.key_factory('existing_field')))

    def test_has_missing_field(self):
        "Test that `has` return False for an existing Storage Field"
        self.assertFalse(self.kvs.has(self.key_factory('missing_field')))
示例#3
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class StorageTestBase(object):
    factory = None
    scope = None
    key_factory = None
    storage_class = None

    def setUp(self):
        field_storage = self.factory.create()
        if hasattr(field_storage, 'student'):
            self.user = field_storage.student
        else:
            self.user = UserFactory.create()
        self.desc_md = {}
        self.mdc = ModelDataCache([mock_descriptor([mock_field(self.scope, 'existing_field')])], course_id, self.user)
        self.kvs = LmsKeyValueStore(self.desc_md, self.mdc)

    def test_get_existing_field(self):
        "Test that getting an existing field in an existing Storage Field works"
        self.assertEquals('old_value', self.kvs.get(self.key_factory('existing_field')))

    def test_get_missing_field(self):
        "Test that getting a missing field from an existing Storage Field raises a KeyError"
        self.assertRaises(KeyError, self.kvs.get, self.key_factory('missing_field'))

    def test_set_existing_field(self):
        "Test that setting an existing field changes the value"
        self.kvs.set(self.key_factory('existing_field'), 'new_value')
        self.assertEquals(1, self.storage_class.objects.all().count())
        self.assertEquals('new_value', json.loads(self.storage_class.objects.all()[0].value))

    def test_set_missing_field(self):
        "Test that setting a new field changes the value"
        self.kvs.set(self.key_factory('missing_field'), 'new_value')
        self.assertEquals(2, self.storage_class.objects.all().count())
        self.assertEquals('old_value', json.loads(self.storage_class.objects.get(field_name='existing_field').value))
        self.assertEquals('new_value', json.loads(self.storage_class.objects.get(field_name='missing_field').value))

    def test_delete_existing_field(self):
        "Test that deleting an existing field removes it"
        self.kvs.delete(self.key_factory('existing_field'))
        self.assertEquals(0, self.storage_class.objects.all().count())

    def test_delete_missing_field(self):
        "Test that deleting a missing field from an existing Storage Field raises a KeyError"
        self.assertRaises(KeyError, self.kvs.delete, self.key_factory('missing_field'))
        self.assertEquals(1, self.storage_class.objects.all().count())

    def test_has_existing_field(self):
        "Test that `has` returns True for an existing Storage Field"
        self.assertTrue(self.kvs.has(self.key_factory('existing_field')))

    def test_has_missing_field(self):
        "Test that `has` return False for an existing Storage Field"
        self.assertFalse(self.kvs.has(self.key_factory('missing_field')))
class TestStudentModuleStorage(TestCase):

    def setUp(self):
        self.desc_md = {}
        student_module = StudentModuleFactory(state=json.dumps({'a_field': 'a_value'}))
        self.user = student_module.student
        self.mdc = ModelDataCache([mock_descriptor([mock_field(Scope.user_state, 'a_field')])], course_id, self.user)
        self.kvs = LmsKeyValueStore(self.desc_md, self.mdc)

    def test_get_existing_field(self):
        "Test that getting an existing field in an existing StudentModule works"
        self.assertEquals('a_value', self.kvs.get(user_state_key('a_field')))

    def test_get_missing_field(self):
        "Test that getting a missing field from an existing StudentModule raises a KeyError"
        self.assertRaises(KeyError, self.kvs.get, user_state_key('not_a_field'))

    def test_set_existing_field(self):
        "Test that setting an existing user_state field changes the value"
        self.kvs.set(user_state_key('a_field'), 'new_value')
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({'a_field': 'new_value'}, json.loads(StudentModule.objects.all()[0].state))

    def test_set_missing_field(self):
        "Test that setting a new user_state field changes the value"
        self.kvs.set(user_state_key('not_a_field'), 'new_value')
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({'a_field': 'a_value', 'not_a_field': 'new_value'}, json.loads(StudentModule.objects.all()[0].state))

    def test_delete_existing_field(self):
        "Test that deleting an existing field removes it from the StudentModule"
        self.kvs.delete(user_state_key('a_field'))
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertRaises(KeyError, self.kvs.get, user_state_key('not_a_field'))

    def test_delete_missing_field(self):
        "Test that deleting a missing field from an existing StudentModule raises a KeyError"
        self.assertRaises(KeyError, self.kvs.delete, user_state_key('not_a_field'))
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({'a_field': 'a_value'}, json.loads(StudentModule.objects.all()[0].state))

    def test_has_existing_field(self):
        "Test that `has` returns True for existing fields in StudentModules"
        self.assertTrue(self.kvs.has(user_state_key('a_field')))

    def test_has_missing_field(self):
        "Test that `has` returns False for missing fields in StudentModule"
        self.assertFalse(self.kvs.has(user_state_key('not_a_field')))
class StorageTestBase(object):
    """
    A base class for that gets subclassed when testing each of the scopes.

    """
    # Disable pylint warnings that arise because of the way the child classes call
    # this base class -- pylint's static analysis can't keep up with it.
    # pylint: disable=E1101, E1102

    factory = None
    scope = None
    key_factory = None
    storage_class = None

    def setUp(self):
        field_storage = self.factory.create()
        if hasattr(field_storage, 'student'):
            self.user = field_storage.student
        else:
            self.user = UserFactory.create()
        self.desc_md = {}
        self.mock_descriptor = mock_descriptor([
            mock_field(self.scope, 'existing_field'),
            mock_field(self.scope, 'other_existing_field')])
        self.mdc = ModelDataCache([self.mock_descriptor], course_id, self.user)
        self.kvs = LmsKeyValueStore(self.desc_md, self.mdc)

    def test_set_and_get_existing_field(self):
        self.kvs.set(self.key_factory('existing_field'), 'test_value')
        self.assertEquals('test_value', self.kvs.get(self.key_factory('existing_field')))

    def test_get_existing_field(self):
        "Test that getting an existing field in an existing Storage Field works"
        self.assertEquals('old_value', self.kvs.get(self.key_factory('existing_field')))

    def test_get_missing_field(self):
        "Test that getting a missing field from an existing Storage Field raises a KeyError"
        self.assertRaises(KeyError, self.kvs.get, self.key_factory('missing_field'))

    def test_set_existing_field(self):
        "Test that setting an existing field changes the value"
        self.kvs.set(self.key_factory('existing_field'), 'new_value')
        self.assertEquals(1, self.storage_class.objects.all().count())
        self.assertEquals('new_value', json.loads(self.storage_class.objects.all()[0].value))

    def test_set_missing_field(self):
        "Test that setting a new field changes the value"
        self.kvs.set(self.key_factory('missing_field'), 'new_value')
        self.assertEquals(2, self.storage_class.objects.all().count())
        self.assertEquals('old_value', json.loads(self.storage_class.objects.get(field_name='existing_field').value))
        self.assertEquals('new_value', json.loads(self.storage_class.objects.get(field_name='missing_field').value))

    def test_delete_existing_field(self):
        "Test that deleting an existing field removes it"
        self.kvs.delete(self.key_factory('existing_field'))
        self.assertEquals(0, self.storage_class.objects.all().count())

    def test_delete_missing_field(self):
        "Test that deleting a missing field from an existing Storage Field raises a KeyError"
        self.assertRaises(KeyError, self.kvs.delete, self.key_factory('missing_field'))
        self.assertEquals(1, self.storage_class.objects.all().count())

    def test_has_existing_field(self):
        "Test that `has` returns True for an existing Storage Field"
        self.assertTrue(self.kvs.has(self.key_factory('existing_field')))

    def test_has_missing_field(self):
        "Test that `has` return False for an existing Storage Field"
        self.assertFalse(self.kvs.has(self.key_factory('missing_field')))

    def construct_kv_dict(self):
        """Construct a kv_dict that can be passed to set_many"""
        key1 = self.key_factory('existing_field')
        key2 = self.key_factory('other_existing_field')
        new_value = 'new value'
        newer_value = 'newer value'
        return {key1: new_value, key2: newer_value}

    def test_set_many(self):
        """Test that setting many regular fields at the same time works"""
        kv_dict = self.construct_kv_dict()

        self.kvs.set_many(kv_dict)
        for key in kv_dict:
            self.assertEquals(self.kvs.get(key), kv_dict[key])

    def test_set_many_failure(self):
        """Test that setting many regular fields with a DB error """
        kv_dict = self.construct_kv_dict()
        for key in kv_dict:
            self.kvs.set(key, 'test value')

        with patch('django.db.models.Model.save', side_effect=[None, DatabaseError]):
            with self.assertRaises(KeyValueMultiSaveError) as exception_context:
                self.kvs.set_many(kv_dict)

        exception = exception_context.exception
        self.assertEquals(len(exception.saved_field_names), 1)
        self.assertEquals(exception.saved_field_names[0], 'existing_field')
class TestStudentModuleStorage(TestCase):

    def setUp(self):
        self.desc_md = {}
        student_module = StudentModuleFactory(state=json.dumps({'a_field': 'a_value', 'b_field': 'b_value'}))
        self.user = student_module.student
        self.mdc = ModelDataCache([mock_descriptor([mock_field(Scope.user_state, 'a_field')])], course_id, self.user)
        self.kvs = LmsKeyValueStore(self.desc_md, self.mdc)

    def test_get_existing_field(self):
        "Test that getting an existing field in an existing StudentModule works"
        self.assertEquals('a_value', self.kvs.get(user_state_key('a_field')))

    def test_get_missing_field(self):
        "Test that getting a missing field from an existing StudentModule raises a KeyError"
        self.assertRaises(KeyError, self.kvs.get, user_state_key('not_a_field'))

    def test_set_existing_field(self):
        "Test that setting an existing user_state field changes the value"
        self.kvs.set(user_state_key('a_field'), 'new_value')
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({'b_field': 'b_value', 'a_field': 'new_value'}, json.loads(StudentModule.objects.all()[0].state))

    def test_set_missing_field(self):
        "Test that setting a new user_state field changes the value"
        self.kvs.set(user_state_key('not_a_field'), 'new_value')
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({'b_field': 'b_value', 'a_field': 'a_value', 'not_a_field': 'new_value'}, json.loads(StudentModule.objects.all()[0].state))

    def test_delete_existing_field(self):
        "Test that deleting an existing field removes it from the StudentModule"
        self.kvs.delete(user_state_key('a_field'))
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertRaises(KeyError, self.kvs.get, user_state_key('not_a_field'))

    def test_delete_missing_field(self):
        "Test that deleting a missing field from an existing StudentModule raises a KeyError"
        self.assertRaises(KeyError, self.kvs.delete, user_state_key('not_a_field'))
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({'b_field': 'b_value', 'a_field': 'a_value'}, json.loads(StudentModule.objects.all()[0].state))

    def test_has_existing_field(self):
        "Test that `has` returns True for existing fields in StudentModules"
        self.assertTrue(self.kvs.has(user_state_key('a_field')))

    def test_has_missing_field(self):
        "Test that `has` returns False for missing fields in StudentModule"
        self.assertFalse(self.kvs.has(user_state_key('not_a_field')))

    def construct_kv_dict(self):
        """Construct a kv_dict that can be passed to set_many"""
        key1 = user_state_key('field_a')
        key2 = user_state_key('field_b')
        new_value = 'new value'
        newer_value = 'newer value'
        return {key1: new_value, key2: newer_value}

    def test_set_many(self):
        "Test setting many fields that are scoped to Scope.user_state"
        kv_dict = self.construct_kv_dict()
        self.kvs.set_many(kv_dict)

        for key in kv_dict:
            self.assertEquals(self.kvs.get(key), kv_dict[key])

    def test_set_many_failure(self):
        "Test failures when setting many fields that are scoped to Scope.user_state"
        kv_dict = self.construct_kv_dict()
        # because we're patching the underlying save, we need to ensure the
        # fields are in the cache
        for key in kv_dict:
            self.kvs.set(key, 'test_value')

        with patch('django.db.models.Model.save', side_effect=DatabaseError):
            with self.assertRaises(KeyValueMultiSaveError) as exception_context:
                self.kvs.set_many(kv_dict)
        self.assertEquals(len(exception_context.exception.saved_field_names), 0)
示例#7
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class StorageTestBase(object):
    """
    A base class for that gets subclassed when testing each of the scopes.

    """
    # Disable pylint warnings that arise because of the way the child classes call
    # this base class -- pylint's static analysis can't keep up with it.
    # pylint: disable=E1101, E1102

    factory = None
    scope = None
    key_factory = None
    storage_class = None

    def setUp(self):
        field_storage = self.factory.create()
        if hasattr(field_storage, 'student'):
            self.user = field_storage.student
        else:
            self.user = UserFactory.create()
        self.desc_md = {}
        self.mock_descriptor = mock_descriptor([
            mock_field(self.scope, 'existing_field'),
            mock_field(self.scope, 'other_existing_field')
        ])
        self.mdc = ModelDataCache([self.mock_descriptor], course_id, self.user)
        self.kvs = LmsKeyValueStore(self.desc_md, self.mdc)

    def test_set_and_get_existing_field(self):
        self.kvs.set(self.key_factory('existing_field'), 'test_value')
        self.assertEquals('test_value',
                          self.kvs.get(self.key_factory('existing_field')))

    def test_get_existing_field(self):
        "Test that getting an existing field in an existing Storage Field works"
        self.assertEquals('old_value',
                          self.kvs.get(self.key_factory('existing_field')))

    def test_get_missing_field(self):
        "Test that getting a missing field from an existing Storage Field raises a KeyError"
        self.assertRaises(KeyError, self.kvs.get,
                          self.key_factory('missing_field'))

    def test_set_existing_field(self):
        "Test that setting an existing field changes the value"
        self.kvs.set(self.key_factory('existing_field'), 'new_value')
        self.assertEquals(1, self.storage_class.objects.all().count())
        self.assertEquals(
            'new_value', json.loads(self.storage_class.objects.all()[0].value))

    def test_set_missing_field(self):
        "Test that setting a new field changes the value"
        self.kvs.set(self.key_factory('missing_field'), 'new_value')
        self.assertEquals(2, self.storage_class.objects.all().count())
        self.assertEquals(
            'old_value',
            json.loads(
                self.storage_class.objects.get(
                    field_name='existing_field').value))
        self.assertEquals(
            'new_value',
            json.loads(
                self.storage_class.objects.get(
                    field_name='missing_field').value))

    def test_delete_existing_field(self):
        "Test that deleting an existing field removes it"
        self.kvs.delete(self.key_factory('existing_field'))
        self.assertEquals(0, self.storage_class.objects.all().count())

    def test_delete_missing_field(self):
        "Test that deleting a missing field from an existing Storage Field raises a KeyError"
        self.assertRaises(KeyError, self.kvs.delete,
                          self.key_factory('missing_field'))
        self.assertEquals(1, self.storage_class.objects.all().count())

    def test_has_existing_field(self):
        "Test that `has` returns True for an existing Storage Field"
        self.assertTrue(self.kvs.has(self.key_factory('existing_field')))

    def test_has_missing_field(self):
        "Test that `has` return False for an existing Storage Field"
        self.assertFalse(self.kvs.has(self.key_factory('missing_field')))

    def construct_kv_dict(self):
        """Construct a kv_dict that can be passed to set_many"""
        key1 = self.key_factory('existing_field')
        key2 = self.key_factory('other_existing_field')
        new_value = 'new value'
        newer_value = 'newer value'
        return {key1: new_value, key2: newer_value}

    def test_set_many(self):
        """Test that setting many regular fields at the same time works"""
        kv_dict = self.construct_kv_dict()

        self.kvs.set_many(kv_dict)
        for key in kv_dict:
            self.assertEquals(self.kvs.get(key), kv_dict[key])

    def test_set_many_failure(self):
        """Test that setting many regular fields with a DB error """
        kv_dict = self.construct_kv_dict()
        for key in kv_dict:
            self.kvs.set(key, 'test value')

        with patch('django.db.models.Model.save',
                   side_effect=[None, DatabaseError]):
            with self.assertRaises(
                    KeyValueMultiSaveError) as exception_context:
                self.kvs.set_many(kv_dict)

        exception = exception_context.exception
        self.assertEquals(len(exception.saved_field_names), 1)
        self.assertEquals(exception.saved_field_names[0], 'existing_field')
示例#8
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class TestStudentModuleStorage(TestCase):
    def setUp(self):
        self.desc_md = {}
        student_module = StudentModuleFactory(
            state=json.dumps({
                'a_field': 'a_value',
                'b_field': 'b_value'
            }))
        self.user = student_module.student
        self.mdc = ModelDataCache(
            [mock_descriptor([mock_field(Scope.user_state, 'a_field')])],
            course_id, self.user)
        self.kvs = LmsKeyValueStore(self.desc_md, self.mdc)

    def test_get_existing_field(self):
        "Test that getting an existing field in an existing StudentModule works"
        self.assertEquals('a_value', self.kvs.get(user_state_key('a_field')))

    def test_get_missing_field(self):
        "Test that getting a missing field from an existing StudentModule raises a KeyError"
        self.assertRaises(KeyError, self.kvs.get,
                          user_state_key('not_a_field'))

    def test_set_existing_field(self):
        "Test that setting an existing user_state field changes the value"
        self.kvs.set(user_state_key('a_field'), 'new_value')
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({
            'b_field': 'b_value',
            'a_field': 'new_value'
        }, json.loads(StudentModule.objects.all()[0].state))

    def test_set_missing_field(self):
        "Test that setting a new user_state field changes the value"
        self.kvs.set(user_state_key('not_a_field'), 'new_value')
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals(
            {
                'b_field': 'b_value',
                'a_field': 'a_value',
                'not_a_field': 'new_value'
            }, json.loads(StudentModule.objects.all()[0].state))

    def test_delete_existing_field(self):
        "Test that deleting an existing field removes it from the StudentModule"
        self.kvs.delete(user_state_key('a_field'))
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertRaises(KeyError, self.kvs.get,
                          user_state_key('not_a_field'))

    def test_delete_missing_field(self):
        "Test that deleting a missing field from an existing StudentModule raises a KeyError"
        self.assertRaises(KeyError, self.kvs.delete,
                          user_state_key('not_a_field'))
        self.assertEquals(1, StudentModule.objects.all().count())
        self.assertEquals({
            'b_field': 'b_value',
            'a_field': 'a_value'
        }, json.loads(StudentModule.objects.all()[0].state))

    def test_has_existing_field(self):
        "Test that `has` returns True for existing fields in StudentModules"
        self.assertTrue(self.kvs.has(user_state_key('a_field')))

    def test_has_missing_field(self):
        "Test that `has` returns False for missing fields in StudentModule"
        self.assertFalse(self.kvs.has(user_state_key('not_a_field')))

    def construct_kv_dict(self):
        """Construct a kv_dict that can be passed to set_many"""
        key1 = user_state_key('field_a')
        key2 = user_state_key('field_b')
        new_value = 'new value'
        newer_value = 'newer value'
        return {key1: new_value, key2: newer_value}

    def test_set_many(self):
        "Test setting many fields that are scoped to Scope.user_state"
        kv_dict = self.construct_kv_dict()
        self.kvs.set_many(kv_dict)

        for key in kv_dict:
            self.assertEquals(self.kvs.get(key), kv_dict[key])

    def test_set_many_failure(self):
        "Test failures when setting many fields that are scoped to Scope.user_state"
        kv_dict = self.construct_kv_dict()
        # because we're patching the underlying save, we need to ensure the
        # fields are in the cache
        for key in kv_dict:
            self.kvs.set(key, 'test_value')

        with patch('django.db.models.Model.save', side_effect=DatabaseError):
            with self.assertRaises(
                    KeyValueMultiSaveError) as exception_context:
                self.kvs.set_many(kv_dict)
        self.assertEquals(len(exception_context.exception.saved_field_names),
                          0)