Cinder objects tests fail with PYTHONHASHSEED != 0

[Eric Harney]

There are a number of failures in Cinder when we let Python randomize hash seeds, but I wanted to call this one out in particular since it's new code and could indicate a meaningful/tricky bug in objects. (I don't really know.)

See bug 1348818 for the general effort of allowing a random PYTHONHASHSEED.

To reproduce, set PYTHONHASHSEED=33 in tox.ini and run
$ tox -e py27 cinder.tests.objects

cinder.tests.objects.test_objects.TestObject.test_base_attributes
-----------------------------------------------------------------

Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):
      File "cinder/tests/objects/test_objects.py", line 589, in test_base_attributes
        self.assertEqual(obj.obj_to_primitive(), expected)
      File "/home/eharney/src/cinder-trunk4/.tox/py27/lib/python2.7/site-packages/testtools/testcase.py", line 350, in assertEqual
        self.assertThat(observed, matcher, message)
      File "/home/eharney/src/cinder-trunk4/.tox/py27/lib/python2.7/site-packages/testtools/testcase.py", line 435, in assertThat
        raise mismatch_error
    testtools.matchers._impl.MismatchError: !=:
    reference = {'cinder_object.changes': ['created_at',
                               'deleted_at',
                               'updated_at',
                               'deleted'],
     'cinder_object.data': {'created_at': '1955-11-05T00:00:00Z',
                            'deleted': False,
                            'deleted_at': None,
                            'updated_at': '1955-11-05T00:00:00Z'},
     'cinder_object.name': 'MyObj',
     'cinder_object.namespace': 'cinder',
     'cinder_object.version': '1.6'}
    actual = {'cinder_object.changes': ['deleted',
                               'created_at',
                               'deleted_at',
                               'updated_at'],
     'cinder_object.data': {'created_at': '1955-11-05T00:00:00Z',
                            'deleted': False,
                            'deleted_at': None,
                            'updated_at': '1955-11-05T00:00:00Z'},
     'cinder_object.name': 'MyObj',
     'cinder_object.namespace': 'cinder',
     'cinder_object.version': '1.6'}

[Thang Pham (thang-pham)]

I am not sure this is really a bug, but the source of it is https://github.com/openstack/cinder/blob/master/cinder/objects/base.py#L485

'cinder_object.changes' are unsorted list. If we sort it during obj_to_primitive(), then this should fix the problem. Once we move to oslo_versionedobjects, this test case and a large portion of the objects base code will be removed.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/167632

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/167632
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=32d70f493a42bb0525113bcbe88c1ecf96a24cea
Submitter: Jenkins
Branch: master

commit 32d70f493a42bb0525113bcbe88c1ecf96a24cea
Author: Thang Pham <email address hidden>
Date: Wed Mar 25 10:54:23 2015 -0400

    Sort list of cinder_object.changes

    If PYTHONHASHSEED is set to a non-zero value,
    test_objects.TestObject.test_base_attributes unit test
    fails. This is because 'cinder_object.changes' key is
    an unsorted list when the object is converted to a
    primitive. The following patch fixes this by sorting
    cinder_object.changes.

    Change-Id: I3a80396c5c897de26e982fa6426e7720a09c1375
    Closes-Bug: #1434154