fup: Move _wait_for_volume_{attach,detach} to os-volume_attachments

As documented in the api-ref this is the API end users would poll to
determine the state of a volume operation so use it in our func tests.

Change-Id: I88e827603bb1cd6265bf234f4286ba3b204c3ce1

Author: lyarwood

nova/tests/functional/integrated_helpers.py

@@ -202,43 +202,36 @@ def _wait_for_instance_action_event(
             'actions: %s. Events in the last matching action: %s'
             % (event_name, actions, events))
 
-    # TODO(lyarwood): Rewrite this waiter to use os-volume_attachments
     def _wait_for_volume_attach(self, server_id, volume_id):
         timeout = 0.0
-        server = self.api.get_server(server_id)
-        attached_vols = [vol['id'] for vol in
-                         server['os-extended-volumes:volumes_attached']]
-
-        while volume_id not in attached_vols and timeout < 10.0:
-            time.sleep(.1)
-            timeout += .1
-            server = self.api.get_server(server_id)
-            attached_vols = [vol['id'] for vol in
-                             server['os-extended-volumes:volumes_attached']]
-
-        if volume_id not in attached_vols:
-            self.fail('Timed out waiting for volume %s to be attached to '
+        while timeout < 10.0:
+            try:
+                self.api.get_server_volume(server_id, volume_id)
+                return
+            except api_client.OpenStackApiNotFoundException:
+                time.sleep(.1)
+                timeout += .1
+
+        attached_vols = self.api.get_server_volumes(server_id)
+        self.fail('Timed out waiting for volume %s to be attached to '
                       'server %s. Currently attached volumes: %s' %
                       (volume_id, server_id, attached_vols))
 
-    # TODO(lyarwood): Rewrite this waiter to use os-volume_attachments
     def _wait_for_volume_detach(self, server_id, volume_id):
         timeout = 0.0
-        server = self.api.get_server(server_id)
-        attached_vols = [vol['id'] for vol in
-                         server['os-extended-volumes:volumes_attached']]
-
-        while volume_id in attached_vols and timeout < 10.0:
-            time.sleep(.1)
-            timeout += .1
-            server = self.api.get_server(server_id)
-            attached_vols = [vol['id'] for vol in
-                             server['os-extended-volumes:volumes_attached']]
-
-        if volume_id in attached_vols:
-            self.fail('Timed out waiting for volume %s to be detached from '
-                      'server %s. Currently attached volumes: %s' %
-                      (volume_id, server_id, attached_vols))
+
+        while timeout < 10.0:
+            try:
+                self.api.get_server_volume(server_id, volume_id)
+                time.sleep(.1)
+                timeout += .1
+            except api_client.OpenStackApiNotFoundException:
+                return
+
+        attached_vols = self.api.get_server_volumes(server_id)
+        self.fail('Timed out waiting for volume %s to be detached from '
+                  'server %s. Currently attached volumes: %s' %
+                  (volume_id, server_id, attached_vols))
 
     def _assert_resize_migrate_action_fail(self, server, action, error_in_tb):
         """Waits for the conductor_migrate_server action event to fail for