tests: Replace use of CONF with monkey patching

Per the docs, the 'nova-console' service is "a XenAPI-specific service
that most recent VNC proxy architectures do not use." [1] This service
provides a config option - 'console_driver' - which only has two valid
values, one of which was a fake used in testing.

There are better ways to stub out code during tests that by setting
configuration options, namely through the use of monkey patching. Do
this, paving the way for deprecation and eventual removal of this
configuration option.

[1] https://github.com/openstack/openstack-manuals/tree/4b1e8f1/doc\
    /admin-guide/source/compute-remote-console-access.rst

Change-Id: Ibfc957c40dafb1ecb35b8658ab92b922b1f39a1a

nova/console/manager.py

@@ -17,10 +17,10 @@
 
 from oslo_log import log as logging
 import oslo_messaging as messaging
-from oslo_utils import importutils
 
 from nova.compute import rpcapi as compute_rpcapi
 import nova.conf
+from nova.console import xvp
 from nova import exception
 from nova.i18n import _LI
 from nova import manager
@@ -41,10 +41,8 @@ class ConsoleProxyManager(manager.Manager):
 
     target = messaging.Target(version='2.0')
 
-    def __init__(self, console_driver=None, *args, **kwargs):
-        if not console_driver:
-            console_driver = CONF.console_driver
-        self.driver = importutils.import_object(console_driver)
+    def __init__(self, *args, **kwargs):
+        self.driver = xvp.XVPConsoleProxy()
         super(ConsoleProxyManager, self).__init__(service_name='console',
                                                   *args, **kwargs)
         self.driver.host = self.host

nova/tests/functional/api_sample_tests/test_consoles.py

@@ -13,8 +13,11 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import fixtures
+
 from nova.console import manager as console_manager  # noqa - only for cfg
 from nova.tests.functional.api_sample_tests import test_servers
+from nova.tests.unit import fake_xvp_console_proxy
 
 
 class ConsolesSamplesJsonTest(test_servers.ServersSampleBase):
@@ -24,7 +27,9 @@ class ConsolesSamplesJsonTest(test_servers.ServersSampleBase):
         super(ConsolesSamplesJsonTest, self).setUp()
         self.flags(console_public_hostname='fake')
         self.flags(console_host='fake')
-        self.flags(console_driver='nova.console.fake.FakeConsoleProxy')
+        self.useFixture(fixtures.MonkeyPatch(
+            'nova.console.manager.xvp.XVPConsoleProxy',
+            fake_xvp_console_proxy.FakeConsoleProxy))
         self.console = self.start_service('console', host='fake')
 
     def _create_consoles(self, server_uuid):

nova/tests/unit/console/test_console.py

@@ -16,6 +16,7 @@
 
 """Tests For Console proxy."""
 
+import fixtures
 import mock
 
 from nova.compute import rpcapi as compute_rpcapi
@@ -28,6 +29,7 @@ from nova import exception
 from nova import objects
 from nova import test
 from nova.tests.unit import fake_instance
+from nova.tests.unit import fake_xvp_console_proxy
 
 CONF = nova.conf.CONF
 
@@ -36,7 +38,9 @@ class ConsoleTestCase(test.TestCase):
     """Test case for console proxy manager."""
     def setUp(self):
         super(ConsoleTestCase, self).setUp()
-        self.flags(console_driver='nova.console.fake.FakeConsoleProxy')
+        self.useFixture(fixtures.MonkeyPatch(
+            'nova.console.manager.xvp.XVPConsoleProxy',
+            fake_xvp_console_proxy.FakeConsoleProxy))
         self.console = console_manager.ConsoleProxyManager()
         self.user_id = 'fake'
         self.project_id = 'fake'