Send a full instance via rpc for finish_revert_resize.

Change the finish_revert_resize method of the compute rpc API to take
a full instance over rpc instead of just the instance UUID.
This cuts down on database access needed by nova-compute.

Part of blueprint no-db-messaging.

Change-Id: Ibe2f8b990cc8f2a3d05e8ba8216a1e74cbcfb67b

nova/compute/manager.py

@@ -298,7 +298,7 @@ def _get_additional_capabilities():
 class ComputeManager(manager.SchedulerDependentManager):
     """Manages the running instances from creation to destruction."""
 
-    RPC_API_VERSION = '1.14'
+    RPC_API_VERSION = '1.15'
 
     def __init__(self, compute_driver=None, *args, **kwargs):
         """Load configuration options and connect to the hypervisor."""
@@ -1449,7 +1449,8 @@ class ComputeManager(manager.SchedulerDependentManager):
     @exception.wrap_exception(notifier=notifier, publisher_id=publisher_id())
     @checks_instance_lock
     @wrap_instance_fault
-    def finish_revert_resize(self, context, instance_uuid, migration_id):
+    def finish_revert_resize(self, context, migration_id, instance_uuid=None,
+                             instance=None):
         """Finishes the second half of reverting a resize.
 
         Power back on the source instance and revert the resized attributes
@@ -1457,23 +1458,24 @@ class ComputeManager(manager.SchedulerDependentManager):
 
         """
         migration_ref = self.db.migration_get(context, migration_id)
-        instance_ref = self.db.instance_get_by_uuid(context,
-                migration_ref.instance_uuid)
-        network_info = self._get_instance_nw_info(context, instance_ref)
+        if not instance:
+            instance = self.db.instance_get_by_uuid(context,
+                    migration_ref.instance_uuid)
+        network_info = self._get_instance_nw_info(context, instance)
 
         self._notify_about_instance_usage(
-                context, instance_ref, "resize.revert.start")
+                context, instance, "resize.revert.start")
 
         old_instance_type = migration_ref['old_instance_type_id']
         instance_type = instance_types.get_instance_type(old_instance_type)
 
-        self.driver.finish_revert_migration(instance_ref,
+        self.driver.finish_revert_migration(instance,
                                    self._legacy_nw_info(network_info))
 
         # Just roll back the record. There's no need to resize down since
         # the 'old' VM already has the preferred attributes
         self._instance_update(context,
-                              instance_ref['uuid'],
+                              instance['uuid'],
                               memory_mb=instance_type['memory_mb'],
                               host=migration_ref['source_compute'],
                               vcpus=instance_type['vcpus'],
@@ -1488,7 +1490,7 @@ class ComputeManager(manager.SchedulerDependentManager):
                 {'status': 'reverted'})
 
         self._notify_about_instance_usage(
-                context, instance_ref, "resize.revert.end")
+                context, instance, "resize.revert.end")
 
     @exception.wrap_exception(notifier=notifier, publisher_id=publisher_id())
     @checks_instance_lock

nova/compute/rpcapi.py

@@ -75,6 +75,8 @@ class ComputeAPI(nova.openstack.common.rpc.proxy.RpcProxy):
         1.12 - Remove instance_uuid, add instance argument to confirm_resize()
         1.13 - Remove instance_uuid, add instance argument to detach_volume()
         1.14 - Remove instance_uuid, add instance argument to finish_resize()
+        1.15 - Remove instance_uuid, add instance argument to
+               finish_revert_resize()
     '''
 
     BASE_RPC_API_VERSION = '1.0'
@@ -156,9 +158,11 @@ class ComputeAPI(nova.openstack.common.rpc.proxy.RpcProxy):
                 version='1.14')
 
     def finish_revert_resize(self, ctxt, instance, migration_id, host):
+        instance_p = jsonutils.to_primitive(instance)
         self.cast(ctxt, self.make_msg('finish_revert_resize',
-                instance_uuid=instance['uuid'], migration_id=migration_id),
-                topic=_compute_topic(self.topic, ctxt, host, None))
+                instance=instance_p, migration_id=migration_id),
+                topic=_compute_topic(self.topic, ctxt, host, None),
+                version='1.15')
 
     def get_console_output(self, ctxt, instance, tail_length):
         instance_p = jsonutils.to_primitive(instance)

nova/tests/compute/test_compute.py

@@ -1376,8 +1376,9 @@ class ComputeTestCase(BaseTestCase):
         # Finally, revert and confirm the old flavor has been applied
         self.compute.revert_resize(context, inst_ref['uuid'],
                 migration_ref['id'])
-        self.compute.finish_revert_resize(context, inst_ref['uuid'],
-                migration_ref['id'])
+        self.compute.finish_revert_resize(context,
+                migration_id=migration_ref['id'],
+                instance=jsonutils.to_primitive(inst_ref))
 
         instance = db.instance_get_by_uuid(context, instance['uuid'])
         self.assertEqual(instance['vm_state'], vm_states.ACTIVE)

nova/tests/compute/test_rpcapi.py

@@ -52,7 +52,8 @@ class ComputeRpcAPITestCase(test.TestCase):
             'add_fixed_ip_to_instance', 'attach_volume',
             'check_can_live_migrate_destination',
             'check_can_live_migrate_source', 'confirm_resize',
-            'detach_volume', 'finish_resize', 'get_console_output',
+            'detach_volume', 'finish_resize', 'finish_revert_resize',
+            'get_console_output',
             'pause_instance', 'reboot_instance', 'suspend_instance',
             'unpause_instance'
         ]
@@ -166,7 +167,8 @@ class ComputeRpcAPITestCase(test.TestCase):
 
     def test_finish_revert_resize(self):
         self._test_compute_api('finish_revert_resize', 'cast',
-                instance=self.fake_instance, migration_id='id', host='host')
+                instance=self.fake_instance, migration_id='id', host='host',
+                version='1.15')
 
     def test_get_console_output(self):
         self._test_compute_api('get_console_output', 'call',