fup: Move _migrate_stub into LibvirtMigrationMixin

Change-Id: I70efe60995568d71d184eadd27adf8918d1909e2

nova/tests/functional/libvirt/base.py

@@ -160,6 +160,31 @@ def _start_compute(hostname, host_info):
         return hostname
 
 
+class LibvirtMigrationMixin(object):
+    """A simple mixin to facilliate successful libvirt live migrations
+
+    Requires that the test class set self.server for the specific test instnace
+    and self.{src,dest} to indicate the direction of the migration. For any
+    scenarios more complex than this they should override _migrate_stub with
+    their own implementation.
+    """
+    def setUp(self):
+        super().setUp()
+        self.useFixture(fixtures.MonkeyPatch(
+            'nova.tests.fixtures.libvirt.Domain.migrateToURI3',
+            self._migrate_stub))
+        self.migrate_stub_ran = False
+
+    def _migrate_stub(self, domain, destination, params, flags):
+        self.dest.driver._host.get_connection().createXML(
+            params['destination_xml'],
+            'fake-createXML-doesnt-care-about-flags')
+        conn = self.src.driver._host.get_connection()
+        dom = conn.lookupByUUIDString(self.server['id'])
+        dom.complete_job()
+        self.migrate_stub_ran = True
+
+
 class LibvirtNeutronFixture(nova_fixtures.NeutronFixture):
     """A custom variant of the stock neutron fixture with more networks.
 

nova/tests/functional/libvirt/test_numa_live_migration.py

@@ -22,7 +22,6 @@
 from nova.compute import resource_tracker as rt
 from nova import context
 from nova import objects
-from nova import test
 from nova.tests.fixtures import libvirt as fakelibvirt
 from nova.tests.functional import integrated_helpers
 from nova.tests.functional.libvirt import base
@@ -32,8 +31,11 @@
 LOG = logging.getLogger(__name__)
 
 
-class NUMALiveMigrationBase(base.ServersTestBase,
-                            integrated_helpers.InstanceHelperMixin):
+class NUMALiveMigrationBase(
+    base.LibvirtMigrationMixin,
+    base.ServersTestBase,
+    integrated_helpers.InstanceHelperMixin
+):
     """Base for all the test classes here. Gives us the NUMATopologyFilter and
     small helper methods.
     """
@@ -64,11 +66,6 @@ def setUp(self):
             '_live_migration_cleanup_flags',
             lambda *args, **kwargs: (True, True)))
 
-    def _migrate_stub(self, domain, destination, params, flags):
-        raise test.TestingException('_migrate_stub() must be implemented in '
-                                    ' tests that expect the live migration '
-                                    ' to start.')
-
     def get_host(self, server_id):
         server = self.api.get_server(server_id)
         return server['OS-EXT-SRV-ATTR:host']
@@ -104,10 +101,6 @@ class NUMALiveMigrationPositiveBase(NUMALiveMigrationBase):
 
     def setUp(self):
         super(NUMALiveMigrationPositiveBase, self).setUp()
-        self.useFixture(fixtures.MonkeyPatch(
-            'nova.tests.fixtures.libvirt.Domain.migrateToURI3',
-            self._migrate_stub))
-        self.migrate_stub_ran = False
 
     def start_computes_and_servers(self):
         # Start 2 computes
@@ -469,6 +462,11 @@ def _test(self, pin_source, pin_cond, expect_success=True):
             hostname='dest',
             host_info=fakelibvirt.HostInfo())
 
+        # This duplication is required to let the LibvirtMigrationMixin know
+        # which host is which in terms of the migration.
+        self.src = self.computes['source']
+        self.dest = self.computes['dest']
+
         ctxt = context.get_admin_context()
         src_mgr = self.computes['source'].manager
         cond_mgr = self.conductor.manager.compute_task_mgr
@@ -507,8 +505,10 @@ def _test(self, pin_source, pin_cond, expect_success=True):
         server2 = self._create_server(flavor_id=flavor, networks='none')
         if self.get_host(server1['id']) == 'source':
             self.migrating_server = server1
+            self.server = server1
         else:
             self.migrating_server = server2
+            self.server = server2
         self.api.post_server_action(
             self.migrating_server['id'],
             {'os-migrateLive': {'host': 'dest',

nova/tests/functional/regressions/test_bug_1939545.py

@@ -12,8 +12,6 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-import fixtures
-
 from oslo_serialization import jsonutils
 
 from nova import context
@@ -24,6 +22,7 @@
 
 
 class TestLiveMigrateUpdateDevicePath(
+    base.LibvirtMigrationMixin,
     base.ServersTestBase,
     integrated_helpers.InstanceHelperMixin
 ):
@@ -43,12 +42,6 @@ class TestLiveMigrateUpdateDevicePath(
     def setUp(self):
         super().setUp()
 
-        # TODO(lyarwood): Move into base.ServersTestBase to allow live
-        # migrations to pass without changes by the test classes.
-        self.useFixture(fixtures.MonkeyPatch(
-            'nova.tests.fixtures.libvirt.Domain.migrateToURI3',
-            self._migrate_stub))
-
         self.start_compute(
             hostname='src',
             host_info=fakelibvirt.HostInfo(
@@ -58,15 +51,8 @@ def setUp(self):
             host_info=fakelibvirt.HostInfo(
                 cpu_nodes=1, cpu_sockets=1, cpu_cores=4, cpu_threads=1))
 
-    def _migrate_stub(self, domain, destination, params, flags):
-        dest = self.computes['dest']
-        dest.driver._host.get_connection().createXML(
-            params['destination_xml'],
-            'fake-createXML-doesnt-care-about-flags')
-        source = self.computes['src']
-        conn = source.driver._host.get_connection()
-        dom = conn.lookupByUUIDString(self.server['id'])
-        dom.complete_job()
+        self.src = self.computes['src']
+        self.dest = self.computes['dest']
 
     def test_live_migrate_update_device_path(self):
         self.server = self._create_server(host='src', networks='none')