Move Nova notification logic out of API controller

Once the decoupling started with 60c05a6d57, this cleanup
patch continues the effort by improving the decoupling
between the API layer and Nova.

Change-Id: I1d7d4b80ee77deefce18df22f76cab81750c0397

neutron/api/v2/base.py

@@ -18,7 +18,6 @@ import copy
 
 import netaddr
 from neutron_lib import exceptions
-from oslo_config import cfg
 from oslo_log import log as logging
 from oslo_policy import policy as oslo_policy
 from oslo_utils import excutils
@@ -90,9 +89,6 @@ class Controller(object):
         self._policy_attrs = [name for (name, info) in self._attr_info.items()
                               if info.get('required_by_policy')]
         self._notifier = n_rpc.get_notifier('network')
-        if cfg.CONF.notify_nova_on_port_data_changes:
-            from neutron.notifiers import nova
-            self._nova_notifier = nova.Notifier()
         self._member_actions = member_actions
         self._primary_key = self._get_primary_key()
         if self._allow_pagination and self._native_pagination:
@@ -327,10 +323,6 @@ class Controller(object):
                            pluralized=self._collection)
         return obj
 
-    def _send_nova_notification(self, action, orig, returned):
-        if hasattr(self, '_nova_notifier'):
-            self._nova_notifier.send_network_change(action, orig, returned)
-
     @db_api.retry_db_errors
     def index(self, request, **kwargs):
         """Returns a list of the requested entity."""
@@ -473,7 +465,8 @@ class Controller(object):
             registry.notify(self._resource, events.BEFORE_RESPONSE, self,
                             context=request.context, data=create_result,
                             method_name=notifier_method,
-                            collection=self._collection)
+                            collection=self._collection,
+                            action=action, original={})
             return create_result
 
         def do_create(body, bulk=False, emulated=False):
@@ -519,8 +512,6 @@ class Controller(object):
                 return notify({self._collection: objs})
             else:
                 obj = do_create(body)
-                self._send_nova_notification(action, {},
-                                             {self._resource: obj})
                 return notify({self._resource: self._view(request.context,
                                                           obj)})
 
@@ -563,10 +554,10 @@ class Controller(object):
                             notifier_method,
                             {self._resource + '_id': id})
         result = {self._resource: self._view(request.context, obj)}
-        self._send_nova_notification(action, {}, result)
         registry.notify(self._resource, events.BEFORE_RESPONSE, self,
                         context=request.context, data=result,
-                        method_name=notifier_method)
+                        method_name=notifier_method, action=action,
+                        original={})
 
     def update(self, request, id, body=None, **kwargs):
         """Updates the specified entity's attributes."""
@@ -637,8 +628,8 @@ class Controller(object):
         self._notifier.info(request.context, notifier_method, result)
         registry.notify(self._resource, events.BEFORE_RESPONSE, self,
                         context=request.context, data=result,
-                        method_name=notifier_method)
-        self._send_nova_notification(action, orig_object_copy, result)
+                        method_name=notifier_method, action=action,
+                        original=orig_object_copy)
         return result
 
     @staticmethod

neutron/notifiers/nova.py

@@ -23,6 +23,9 @@ from oslo_utils import uuidutils
 from sqlalchemy.orm import attributes as sql_attr
 
 from neutron._i18n import _LE, _LI, _LW
+from neutron.callbacks import events
+from neutron.callbacks import registry
+from neutron.callbacks import resources
 from neutron import context
 from neutron import manager
 from neutron.notifiers import batch_notifier
@@ -68,6 +71,15 @@ class Notifier(object):
         self.batch_notifier = batch_notifier.BatchNotifier(
             cfg.CONF.send_events_interval, self.send_events)
 
+        # register callbacks for events pertaining resources affecting Nova
+        callback_resources = (
+            resources.FLOATING_IP,
+            resources.PORT,
+        )
+        for resource in callback_resources:
+            registry.subscribe(self._send_nova_notification,
+                               resource, events.BEFORE_RESPONSE)
+
     def _is_compute_port(self, port):
         try:
             if (port['device_id'] and uuidutils.is_uuid_like(port['device_id'])
@@ -96,6 +108,11 @@ class Notifier(object):
             self._plugin_ref = manager.NeutronManager.get_plugin()
         return self._plugin_ref
 
+    def _send_nova_notification(self, resource, event, trigger,
+                                action=None, original=None, data=None,
+                                **kwargs):
+        self.send_network_change(action, original, data)
+
     def send_network_change(self, action, original_obj,
                             returned_obj):
         """Called when a network change is made that nova cares about.