test_auth_middleware_factory fails with new keystonemiddleware 5.1.0

[melanie witt]

As seen in the review to update the constraint for keystoneauthmiddleware [1], the test_auth_middleware_factory unit test fails with:

Traceback (most recent call last):
  File "nova/tests/unit/api/openstack/placement/test_deploy.py", line 43, in test_auth_middleware_factory
    response.headers['www-authenticate'])
  File "/home/zuul/src/git.openstack.org/openstack/nova/.tox/py27/local/lib/python2.7/site-packages/testtools/testcase.py", line 411, in assertEqual
    self.assertThat(observed, matcher, message)
  File "/home/zuul/src/git.openstack.org/openstack/nova/.tox/py27/local/lib/python2.7/site-packages/testtools/testcase.py", line 498, in assertThat
    raise mismatch_error
testtools.matchers._impl.MismatchError: !=:
reference = "Keystone uri='http://example.com/identity'"
actual = 'Keystone uri="http://example.com/identity"'

cdent found this is the result of a fairly recent change [2] that updated the format of the uri string.

[1] https://review.openstack.org/567449
[2] https://review.openstack.org/559925

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/567923

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/567923
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=46d919c11ba3ad3324b175aae78f3535b231dc27
Submitter: Zuul
Branch: master

commit 46d919c11ba3ad3324b175aae78f3535b231dc27
Author: Chris Dent <email address hidden>
Date: Fri May 11 19:12:40 2018 +0100

    Flexibly test keystonmiddleware in placement stack

    In change I524c93d30607ea6ab70de92ceea207ee77f34c25 keystonemiddleware
    adjusted how the value of the Keystone uri is quoted when sending a
    www-authenticate header. It went from using a single quote to double.
    Double is more correct.

    The existing version of the test changed in this commit relied on the
    single quote to verify that a URL set in config would be used by the
    middleware appropriately. Now, instead of one exact match test, two
    in-string tests are used.

    Change-Id: Ie9d1df419f2bdfa1d658f5f64ea9b7285de7b9b7
    Closes-Bug: #1770718

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 18.0.0.0b2 development milestone.