Revert "Update migration notification"

This reverts commit 6d96512188.

The instance.live_migration_post.end event is created in the source node
before the migration has finished, it shows state migrating and the
source node as host.

The instance.live_migration_post_dest.end is created in the destination
after the migraion is finished, shows task_state None and the correct
destination node as host.

It also adds a release note.

Closes-Bug: #2138857
Change-Id: I751170e4ba1aa5ede0559dae8380120611ecf1e4
Signed-off-by: Alfredo Moralejo <amoralej@redhat.com>

releasenotes/notes/bug-2138857-e3505aa4a20a7831.yaml

@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    Notification-based updates of the nova DataModel failed to set the
+    actual destination host as compute node after Live Migrations. The
+    Nova collector is now using the right Nova notification to update
+    the instance in the DataModel after those events.

watcher/decision_engine/model/notification/nova.py

@@ -340,7 +340,7 @@ class VersionedNotification(NovaNotification):
         'instance.rescue.end': instance_updated,
         'instance.update': instance_updated,
         'instance.live_migration_force_complete.end': instance_updated,
-        'instance.live_migration_post.end': instance_updated,
+        'instance.live_migration_post_dest.end': instance_updated,
         'instance.delete.end': instance_deleted,
         'instance.soft_delete.end': instance_deleted,
         'service.create': service_updated,

watcher/tests/unit/decision_engine/model/notification/data/instance-live_migration_post_dest-end.json

@@ -1,5 +1,5 @@
 {
-    "event_type": "instance.live_migration_post.end",
+    "event_type": "instance.live_migration_post_dest.end",
     "payload": {
         "nova_object.data": {
             "action_initiator_project": "6f70656e737461636b20342065766572",
@@ -49,7 +49,7 @@
                 "nova_object.namespace": "nova",
                 "nova_object.version": "1.4"
             },
-            "host": "Node_1",
+            "host": "host2",
             "host_name": "some-server",
             "image_uuid": "155d900f-4e14-4e4c-a73d-069cbf4541e6",
             "ip_addresses": [

watcher/tests/unit/decision_engine/model/notification/test_nova_notifications.py

@@ -71,8 +71,8 @@ class TestReceiveNovaNotifications(NotificationTestCase):
         'instance.update': 'instance-update.json',
         'instance.live_migration_force_complete.end':
         'instance-live_migration_force_complete-end.json',
-        'instance.live_migration_post.end':
-        'instance-live_migration_post-end.json',
+        'instance.live_migration_post_dest.end':
+        'instance-live_migration_post_dest-end.json',
         'instance.delete.end': 'instance-delete-end.json',
         'instance.soft_delete.end': 'instance-soft_delete-end.json',
         'service.create': 'service-create.json',
@@ -545,7 +545,7 @@ class TestNovaNotifications(NotificationTestCase):
         node = compute_model.get_node_by_instance_uuid(instance0_uuid)
         self.assertEqual('fa69c544-906b-4a6a-a9c6-c1f7a8078c73', node.uuid)
         message = self.load_message(
-            'instance-live_migration_post-end.json')
+            'instance-live_migration_post_dest-end.json')
         handler.info(
             ctxt=self.context,
             publisher_id=message['publisher_id'],