Add functional live migrate test

Live migration now seems to be failing, as after the movement of the VM,
the allocations are both present on the source host, and on the
destination host.
The related assertions are commented out and replaced with wrong ones to
make the test pass.

Change-Id: Ib15d34c8da14dd006a0782e325d3c5e7b83fd0f1
Related-Bug: #1712045

nova/tests/functional/test_servers.py

@@ -1863,3 +1863,58 @@ class ServerMovingTests(test.TestCase, integrated_helpers.InstanceHelperMixin):
 
         self._delete_and_check_allocations(
             server, source_rp_uuid, dest_rp_uuid)
+
+    def test_live_migrate(self):
+        source_hostname = self.compute1.host
+        dest_hostname = self.compute2.host
+        source_rp_uuid = self._get_provider_uuid_by_host(source_hostname)
+        dest_rp_uuid = self._get_provider_uuid_by_host(dest_hostname)
+
+        server = self._boot_and_check_allocations(
+            self.flavor1, source_hostname)
+        post = {
+            'os-migrateLive': {
+                'host': dest_hostname,
+                'block_migration': True,
+            }
+        }
+
+        self.api.post_server_action(server['id'], post)
+        self._wait_for_server_parameter(self.api, server,
+                                        {'OS-EXT-SRV-ATTR:host': dest_hostname,
+                                         'status': 'ACTIVE'})
+
+        self._run_periodics()
+
+        source_usages = self._get_provider_usages(source_rp_uuid)
+        # NOTE(lajos katona): After bug 1712045 is solved on the source there
+        # will be no allocations:
+        # self.assertFlavorMatchesAllocation(
+        #     {'ram': 0, 'disk': 0, 'vcpus': 0}, source_usages)
+
+        # NOTE(lajos katona): while bug 1712045 is not solved on the source
+        # host the allocations are remaining:
+        # on the original host should not have the old resource usage
+        self.assertFlavorMatchesAllocation(self.flavor1, source_usages)
+
+        dest_usages = self._get_provider_usages(dest_rp_uuid)
+        self.assertFlavorMatchesAllocation(self.flavor1, dest_usages)
+
+        allocations = self._get_allocations_by_server_uuid(server['id'])
+        # NOTE(lajos katona): the server has 2 allocations, instead of one,
+        # after bug 1712045 will be solved we can expect just one allocation
+        self.assertEqual(2, len(allocations))
+
+        # NOTE(lajos katona): When bug 1712045 is solved the server has
+        # no allocation on the source:
+        # self.assertNotIn(source_rp_uuid, allocations)
+
+        # Instead the source allocation is still there
+        source_allocation = allocations[source_rp_uuid]['resources']
+        self.assertFlavorMatchesAllocation(self.flavor1, source_allocation)
+
+        dest_allocation = allocations[dest_rp_uuid]['resources']
+        self.assertFlavorMatchesAllocation(self.flavor1, dest_allocation)
+
+        self._delete_and_check_allocations(
+            server, source_rp_uuid, dest_rp_uuid)