Add missing port UPDATE event to ML2

The ML2 plugin was missing a port AFTER_UPDATE event in its
binding commit operations. This was resulting in port binding
results not being serialized for push notifications.

This patch just adds in the AFTER_UPDATE event to the port
binding commit operation.

Partially-Implements: blueprint push-notifications
Change-Id: I67276a3efe97b60499601b1aceeee27ad8961062

neutron/plugins/ml2/plugin.py

@@ -531,6 +531,14 @@ class Ml2Plugin(db_base_plugin_v2.NeutronDbPluginV2,
             # just finished, whether that transaction committed new
             # results or discovered concurrent port state changes.
             # Also, Trigger notification for successful binding commit.
+            kwargs = {
+                'context': plugin_context,
+                'port': port,
+                'mac_address_updated': False,
+                'original_port': oport,
+            }
+            registry.notify(resources.PORT, events.AFTER_UPDATE,
+                            self, **kwargs)
             self.mechanism_manager.update_port_postcommit(cur_context)
             need_notify = True
             try_again = False

neutron/tests/functional/services/l3_router/test_l3_dvr_router_plugin.py

@@ -36,6 +36,10 @@ class L3DvrTestCaseBase(ml2_test_base.ML2TestFramework):
         super(L3DvrTestCaseBase, self).setUp()
         self.l3_agent = helpers.register_l3_agent(
             agent_mode=constants.L3_AGENT_MODE_DVR_SNAT)
+        # register OVS agents to avoid time wasted on committing
+        # port binding failures on every port update
+        helpers.register_ovs_agent(host='host1')
+        helpers.register_ovs_agent(host='host2')
 
     def _create_router(self, distributed=True, ha=False, admin_state_up=True):
         return (super(L3DvrTestCaseBase, self).
@@ -1137,7 +1141,9 @@ class L3DvrTestCase(L3DvrTestCaseBase):
                     self.context, vm_port['port']['id'],
                     {'port': {
                         portbindings.PROFILE: live_migration_port_profile}})
-                l3_notifier.routers_updated_on_host.assert_called_once_with(
+                # this will be called twice, once for port update, and once
+                # for new binding
+                l3_notifier.routers_updated_on_host.assert_any_call(
                     self.context, {router['id']}, HOST2)
                 # Check the port-binding is still with the old HOST1, but
                 # the router update notification has been sent to the new
@@ -1149,7 +1155,7 @@ class L3DvrTestCase(L3DvrTestCaseBase):
                     # Since we have already created the floatingip for the
                     # port, it should be creating the floatingip agent gw
                     # port for the new host if it does not exist.
-                    fip_agent.assert_called_once_with(
+                    fip_agent.assert_any_call(
                         mock.ANY, floating_ip['floating_network_id'], HOST2)
 
     def test_router_notifications(self):

neutron/tests/unit/plugins/ml2/test_plugin.py

@@ -1050,6 +1050,23 @@ class TestMl2PortsV2(test_plugin.TestPortsV2, Ml2PluginV2TestCase):
             # check that notifier was still triggered
             self.assertTrue(notify.call_counts)
 
+    def test_registry_notify_after_port_binding(self):
+        plugin = directory.get_plugin()
+        ctx = context.get_admin_context()
+        update_events = []
+        receiver = lambda *a, **k: update_events.append(k['port'])
+        registry.subscribe(receiver, resources.PORT,
+                           events.AFTER_UPDATE)
+        with self.port() as p:
+            port = {'port': {'binding:host_id': 'newhost'}}
+            plugin.update_port(ctx, p['port']['id'], port)
+        # updating in the host should result in two AFTER_UPDATE events.
+        # one to change the host_id, the second to commit a binding
+        self.assertEqual('newhost', update_events[0]['binding:host_id'])
+        self.assertEqual('unbound', update_events[0]['binding:vif_type'])
+        self.assertEqual('newhost', update_events[1]['binding:host_id'])
+        self.assertNotEqual('unbound', update_events[1]['binding:vif_type'])
+
     def test_check_if_compute_port_serviced_by_dvr(self):
         self.assertTrue(utils.is_dvr_serviced(DEVICE_OWNER_COMPUTE))
 
@@ -2572,16 +2589,25 @@ class TestMl2PluginCreateUpdateDeletePort(base.BaseTestCase):
             plugin = self._create_plugin_for_create_update_port()
             original_port = plugin._make_port_dict(original_port_db)
 
-            plugin.update_port(self.context, port_id, mock.MagicMock())
+            res = plugin.update_port(self.context, port_id, mock.MagicMock())
 
-            kwargs = {
+            first_update = {
                 'context': self.context,
                 'port': updated_port,
                 'mac_address_updated': True,
                 'original_port': original_port,
             }
-            self.notify.assert_called_once_with('port', 'after_update',
-                plugin, **kwargs)
+            bind_update = {
+                'context': self.context,
+                'port': res,
+                'mac_address_updated': False,
+                'original_port': original_port,
+            }
+            expected = [
+                mock.call('port', 'after_update', plugin, **first_update),
+                mock.call('port', 'after_update', plugin, **bind_update)
+            ]
+            self.notify.assert_has_calls(expected)
 
     def test_notify_outside_of_delete_transaction(self):
         self.notify.side_effect = (