nova xenapi unit tests fail with os-xenapi 0.3.0

[Matt Riedemann]

Noticed here: https://review.openstack.org/#/c/500770/

Failures are here: http://logs.openstack.org/70/500770/3/check/gate-cross-nova-python27-ubuntu-xenial/1305547/testr_results.html.gz

For example:

nova.tests.unit.compute.test_compute_xen.ComputeXenTestCase.test_sync_power_states_instance_not_found_StringException: pythonlogging:'': {{{2017-09-05 17:33:49,276 INFO [nova.virt.driver] Loading compute driver 'xenapi.XenAPIDriver'}}}

Traceback (most recent call last):
  File "nova/tests/unit/compute/test_compute_xen.py", line 40, in setUp
    self.compute = manager.ComputeManager()
  File "nova/compute/manager.py", line 541, in __init__
    self.driver = driver.load_compute_driver(self.virtapi, compute_driver)
  File "nova/virt/driver.py", line 1609, in load_compute_driver
    virtapi)
  File "/home/jenkins/workspace/gate-cross-nova-python27-ubuntu-xenial/.tox/py27/local/lib/python2.7/site-packages/oslo_utils/importutils.py", line 44, in import_object
    return import_class(import_str)(*args, **kwargs)
  File "nova/virt/xenapi/driver.py", line 90, in __init__
    originator="nova")
  File "/home/jenkins/workspace/gate-cross-nova-python27-ubuntu-xenial/.tox/py27/local/lib/python2.7/site-packages/os_xenapi/client/session.py", line 90, in __init__
    self.ip = self._get_ip_from_url(url)
  File "/home/jenkins/workspace/gate-cross-nova-python27-ubuntu-xenial/.tox/py27/local/lib/python2.7/site-packages/os_xenapi/client/session.py", line 137, in _get_ip_from_url
    return socket.gethostbyname(url_parts.netloc)
  File "/home/jenkins/workspace/gate-cross-nova-python27-ubuntu-xenial/.tox/py27/local/lib/python2.7/site-packages/eventlet/support/greendns.py", line 477, in gethostbyname
    rrset = resolve(hostname)
  File "/home/jenkins/workspace/gate-cross-nova-python27-ubuntu-xenial/.tox/py27/local/lib/python2.7/site-packages/eventlet/support/greendns.py", line 364, in resolve
    raise EAI_NODATA_ERROR
socket.gaierror: [Errno -5] No address associated with hostname

It looks like this is due to this change that went into os-xenapi 0.3.0:

https://review.openstack.org/#/c/485933/

I don't know if this is an issue in os-xenapi (regression) or if nova needs to now start stubbing out the XenAPISession init code.

It looks like the unit tests within os-xenapi are mocking out the call to the socket module:

https://github.com/openstack/os-xenapi/blob/0.3.0/os_xenapi/tests/client/test_session.py#L32

It would be nice if there were a fixture class in the os-xenapi library that nova's xenapi unit tests could load and that would perform the proper stubs like this.

[Matt Riedemann (mriedem)]

I think the other possible reason this could be failing the unit tests is that the url being passed in is None, since it comes from CONF.xenserver.connection_url and that's not set globally in tests.

[Matt Riedemann (mriedem)]

Yeah this used to cause a 500 in the placement API but that was changed to a 400:

https://review.openstack.org/#/c/499270/

Good spot on where we're doing this incorrectly though during evacuation.

[Matt Riedemann (mriedem)]

Ignore comment 2, that was for another bug.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/500968

[Bob Ball (bob-ball)]

We didn't realise this would be picked up here - this is fixed in https://review.openstack.org/#/c/499573/3 which is a dependency of the global-requirements change at https://review.openstack.org/#/c/500554/

Generally I really don't like that Nova understands the internals of os-xenapi, hence my more comprehensive change to mock out the right things.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/500968
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=81b99caae021593ba65f2fe6a2dbc0f9532d1c70
Submitter: Jenkins
Branch: master

commit 81b99caae021593ba65f2fe6a2dbc0f9532d1c70
Author: Matt Riedemann <email address hidden>
Date: Tue Sep 5 16:06:31 2017 -0400

    Make xen unit tests work with os-xenapi>=0.3.0

    Change Ie1b49a206b57219083059871f326926cc4628142 in os-xenapi
    0.3.0 requires that the URL passed into the XenAPISession is
    an actual URL, which means we need to fix a bunch of unit tests.

    Change-Id: Ida4b8c33e8b3bbd03548648f8e57d923b255f35c
    Closes-Bug: #1715217

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 17.0.0.0b1 development milestone.