oslo.db/oslo_db/tests/sqlalchemy/test_models.py
Victor Stinner 2e79681670 Fix sqlalchemy.ModelBase.__contains__() behaviour
Currently, sqlalchemy.ModelBase.__contains__() catches any exception,
and by doing that, it hides real bugs. For example, a Nova unit test
raises the following error, but __contains__() simply returns False:

    sqlalchemy.orm.exc.DetachedInstanceError: Parent instance
    <InstanceExtra at 0x7fea635bc5f8> is not bound to a Session;
    deferred load operation of attribute 'pci_requests' cannot proceed

On Python 3, hasattr() calls getattr(): it returns True if getattr()
succeeds, False if getattr() raises an AttributeError, or passes
through the exception, if getattr() failed for a different reason.

On Python 2, hasattr() also calls getattr(), but it catches *any*
exception.

This change replaces hasattr() with getattr(), and it only catches
AttributeError as Python 3, so passes through sqlalchemy exceptions.

Add an unit test to test the new behaviour.

Closes-Bug: #1469225

Change-Id: If9c3ccc03f1dc9746936b0b83ea132508491e577
2015-06-26 19:02:53 +03:00

182 lines
5.4 KiB
Python

# Copyright 2012 Cloudscaling Group, Inc.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import collections
from oslotest import base as oslo_test
from sqlalchemy import Column
from sqlalchemy import Integer, String
from sqlalchemy.ext.declarative import declarative_base
from oslo_db.sqlalchemy import models
from oslo_db.sqlalchemy import test_base
BASE = declarative_base()
class ModelBaseTest(test_base.DbTestCase):
def setUp(self):
super(ModelBaseTest, self).setUp()
self.mb = models.ModelBase()
self.ekm = ExtraKeysModel()
def test_modelbase_has_dict_methods(self):
dict_methods = ('__getitem__',
'__setitem__',
'__contains__',
'get',
'update',
'save',
'items',
'iteritems',
'keys')
for method in dict_methods:
self.assertTrue(hasattr(models.ModelBase, method),
"Method %s() is not found" % method)
def test_modelbase_is_iterable(self):
self.assertTrue(issubclass(models.ModelBase, collections.Iterable))
def test_modelbase_set(self):
self.mb['world'] = 'hello'
self.assertEqual(self.mb['world'], 'hello')
def test_modelbase_update(self):
h = {'a': '1', 'b': '2'}
self.mb.update(h)
for key in h.keys():
self.assertEqual(self.mb[key], h[key])
def test_modelbase_contains(self):
mb = models.ModelBase()
h = {'a': '1', 'b': '2'}
mb.update(h)
for key in h.keys():
# Test 'in' syntax (instead of using .assertIn)
self.assertTrue(key in mb)
self.assertFalse('non-existent-key' in mb)
def test_modelbase_contains_exc(self):
class ErrorModel(models.ModelBase):
@property
def bug(self):
raise ValueError
model = ErrorModel()
model.update({'attr': 5})
self.assertTrue('attr' in model)
self.assertRaises(ValueError, lambda: 'bug' in model)
def test_modelbase_items_iteritems(self):
h = {'a': '1', 'b': '2'}
expected = {
'id': None,
'smth': None,
'name': 'NAME',
'a': '1',
'b': '2',
}
self.ekm.update(h)
self.assertEqual(dict(self.ekm.items()), expected)
self.assertEqual(dict(self.ekm.iteritems()), expected)
def test_modelbase_dict(self):
h = {'a': '1', 'b': '2'}
expected = {
'id': None,
'smth': None,
'name': 'NAME',
'a': '1',
'b': '2',
}
self.ekm.update(h)
self.assertEqual(dict(self.ekm), expected)
def test_modelbase_iter(self):
expected = {
'id': None,
'smth': None,
'name': 'NAME',
}
i = iter(self.ekm)
found_items = 0
while True:
r = next(i, None)
if r is None:
break
self.assertEqual(expected[r[0]], r[1])
found_items += 1
self.assertEqual(len(expected), found_items)
def test_modelbase_keys(self):
self.assertEqual(set(self.ekm.keys()),
set(('id', 'smth', 'name')))
self.ekm.update({'a': '1', 'b': '2'})
self.assertEqual(set(self.ekm.keys()),
set(('a', 'b', 'id', 'smth', 'name')))
def test_modelbase_several_iters(self):
mb = ExtraKeysModel()
it1 = iter(mb)
it2 = iter(mb)
self.assertFalse(it1 is it2)
self.assertEqual(dict(it1), dict(mb))
self.assertEqual(dict(it2), dict(mb))
def test_extra_keys_empty(self):
"""Test verifies that by default extra_keys return empty list."""
self.assertEqual(self.mb._extra_keys, [])
def test_extra_keys_defined(self):
"""Property _extra_keys will return list with attributes names."""
self.assertEqual(self.ekm._extra_keys, ['name'])
def test_model_with_extra_keys(self):
data = dict(self.ekm)
self.assertEqual(data, {'smth': None,
'id': None,
'name': 'NAME'})
class ExtraKeysModel(BASE, models.ModelBase):
__tablename__ = 'test_model'
id = Column(Integer, primary_key=True)
smth = Column(String(255))
@property
def name(self):
return 'NAME'
@property
def _extra_keys(self):
return ['name']
class TimestampMixinTest(oslo_test.BaseTestCase):
def test_timestampmixin_attr(self):
methods = ('created_at',
'updated_at')
for method in methods:
self.assertTrue(hasattr(models.TimestampMixin, method),
"Method %s() is not found" % method)