Sync server_external_events v2 to v2.1 Part 1

This syncs commit I18062b81e50c722ec96b4296ac39384493683ae3 which
was made to the v2 version of os-server-external-events but not
the v2.1 version.

Partially implements blueprint v2-on-v3-api

Change-Id: If0657744fac021f635ce292142c82239751ae2f2

nova/api/openstack/compute/plugins/v3/server_external_events.py

@@ -43,7 +43,7 @@ def create(self, req, body):
         context = req.environ['nova.context']
         authorize(context, action='create')
 
-        events = []
+        response_events = []
         accepted = []
         instances = {}
         result = 200
@@ -74,8 +74,8 @@ def create(self, req, body):
                 raise webob.exc.HTTPBadRequest(
                     _('Invalid event status `%s\'') % event.status)
 
-            events.append(_event)
-            if event.instance_uuid not in instances:
+            instance = instances.get(event.instance_uuid)
+            if not instance:
                 try:
                     instance = objects.Instance.get_by_uuid(
                         context, event.instance_uuid)
@@ -88,24 +88,40 @@ def create(self, req, body):
                     _event['code'] = 404
                     result = 207
 
-            if event.instance_uuid in instances:
-                accepted.append(event)
-                _event['code'] = 200
-                LOG.audit(_('Create event %(name)s:%(tag)s for instance '
-                            '%(instance_uuid)s'),
-                          dict(event.iteritems()))
+            # NOTE: before accepting the event, make sure the instance
+            # for which the event is sent is assigned to a host; otherwise
+            # it will not be possible to dispatch the event
+            if instance:
+                if instance.host:
+                    accepted.append(event)
+                    LOG.audit(_('Creating event %(name)s:%(tag)s for instance '
+                                '%(instance_uuid)s'),
+                              dict(event.iteritems()))
+                    # NOTE: as the event is processed asynchronously verify
+                    # whether 202 is a more suitable response code than 200
+                    _event['status'] = 'completed'
+                    _event['code'] = 200
+                else:
+                    LOG.debug("Unable to find a host for instance "
+                              "%(instance)s. Dropping event %(event)s",
+                              {'instance': event.instance_uuid,
+                               'event': event.name})
+                    _event['status'] = 'failed'
+                    _event['code'] = 422
+                    result = 207
+
+            response_events.append(_event)
 
         if accepted:
-            self.compute_api.external_instance_event(context,
-                                                     instances.values(),
-                                                     accepted)
+            self.compute_api.external_instance_event(
+                context, instances.values(), accepted)
         else:
             msg = _('No instances found for any event')
             raise webob.exc.HTTPNotFound(explanation=msg)
 
         # FIXME(cyeoh): This needs some infrastructure support so that
         # we have a general way to do this
-        robj = wsgi.ResponseObject({'events': events})
+        robj = wsgi.ResponseObject({'events': response_events})
         robj._code = result
         return robj
 

nova/tests/unit/api/openstack/compute/plugins/v3/test_server_external_events.py

@@ -29,9 +29,11 @@
         uuid='00000000-0000-0000-0000-000000000002', host='host1'),
     '00000000-0000-0000-0000-000000000003': objects.Instance(
         uuid='00000000-0000-0000-0000-000000000003', host='host2'),
+    '00000000-0000-0000-0000-000000000004': objects.Instance(
+        uuid='00000000-0000-0000-0000-000000000004', host=None),
 }
 fake_instance_uuids = sorted(fake_instances.keys())
-MISSING_UUID = '00000000-0000-0000-0000-000000000004'
+MISSING_UUID = '00000000-0000-0000-0000-000000000005'
 
 
 @classmethod
@@ -48,17 +50,20 @@ def setUp(self):
         super(ServerExternalEventsTest, self).setUp()
         self.api = server_external_events.ServerExternalEventsController()
         self.context = context.get_admin_context()
-        self.default_body = {
-            'events': [
-                {'name': 'network-vif-plugged',
-                 'tag': 'foo',
-                 'status': 'completed',
-                 'server_uuid': fake_instance_uuids[0]},
-                {'name': 'network-changed',
-                 'status': 'completed',
-                 'server_uuid': fake_instance_uuids[1]},
-                ]
-            }
+        self.event_1 = {'name': 'network-vif-plugged',
+                        'tag': 'foo',
+                        'server_uuid': fake_instance_uuids[0]}
+        self.event_2 = {'name': 'network-changed',
+                        'server_uuid': fake_instance_uuids[1]}
+        self.default_body = {'events': [self.event_1, self.event_2]}
+        self.resp_event_1 = dict(self.event_1)
+        self.resp_event_1['code'] = 200
+        self.resp_event_1['status'] = 'completed'
+        self.resp_event_2 = dict(self.event_2)
+        self.resp_event_2['code'] = 200
+        self.resp_event_2['status'] = 'completed'
+        self.default_resp_body = {'events': [self.resp_event_1,
+                                             self.resp_event_2]}
 
     def _create_req(self, body):
         req = webob.Request.blank('/v2/fake/os-server-external-events')
@@ -91,7 +96,7 @@ def test_create(self):
                                          fake_instance_uuids[:2],
                                          ['network-vif-plugged',
                                           'network-changed'])
-        self.assertEqual(self.default_body, result)
+        self.assertEqual(self.default_resp_body, result)
         self.assertEqual(200, code)
 
     def test_create_one_bad_instance(self):
@@ -105,6 +110,19 @@ def test_create_one_bad_instance(self):
         self.assertEqual(404, result['events'][1]['code'])
         self.assertEqual(207, code)
 
+    def test_create_event_instance_has_no_host(self):
+        body = self.default_body
+        body['events'][0]['server_uuid'] = fake_instance_uuids[-1]
+        req = self._create_req(body)
+        result, code = self._assert_call(req, body,
+                                         [fake_instance_uuids[1],
+                                          fake_instance_uuids[-1]],
+                                         ['network-changed'])
+        self.assertEqual(422, result['events'][0]['code'])
+        self.assertEqual('failed', result['events'][0]['status'])
+        self.assertEqual(200, result['events'][1]['code'])
+        self.assertEqual(207, code)
+
     def test_create_no_good_instances(self):
         body = self.default_body
         body['events'][0]['server_uuid'] = MISSING_UUID