Fix load balancer update with provider filtered params

When only setting tags to an existing load balancer, the amphora driver
would try to apply QoS policy on VRRP ports even if no policy is
defined. This raised an NetworkException that led load balancers to go
into ERROR.

Task: 37589
Story: 2006922

Change-Id: I48315f8f293811e1d99584ea36da05c4211cf275
(cherry picked from commit 2cfcd71a86)
(cherry picked from commit 535dc7c698)

octavia/controller/worker/tasks/network_tasks.py

@@ -595,7 +595,7 @@ class ApplyQos(BaseNetworkTask):
         """Apply qos policy on the vrrp ports which are related with vip."""
         qos_policy_id = loadbalancer.vip.qos_policy_id
         if not qos_policy_id and (
-            update_dict and (
+            not update_dict or (
                 'vip' not in update_dict or
                 'qos_policy_id' not in update_dict['vip'])):
             return

octavia/tests/unit/controller/worker/tasks/test_network_tasks.py

@@ -571,6 +571,22 @@ class TestNetworkTasks(base.TestCase):
             t_constants.MOCK_QOS_POLICY_ID1, mock.ANY)
         self.assertEqual(2, mock_driver.apply_qos_on_port.call_count)
 
+        mock_driver.reset_mock()
+        update_dict = {'description': 'fool',
+                       'vip': {
+                           'qos_policy_id': t_constants.MOCK_QOS_POLICY_ID1}}
+        tmp_lb.amphorae = AMPS_DATA
+        tmp_lb.topology = constants.TOPOLOGY_ACTIVE_STANDBY
+        net.execute(tmp_lb, update_dict=update_dict)
+        mock_driver.apply_qos_on_port.assert_called_with(
+            t_constants.MOCK_QOS_POLICY_ID1, mock.ANY)
+        self.assertEqual(2, mock_driver.apply_qos_on_port.call_count)
+
+        mock_driver.reset_mock()
+        update_dict = {}
+        net.execute(null_qos_lb, update_dict=update_dict)
+        self.assertEqual(0, mock_driver.apply_qos_on_port.call_count)
+
         # revert
         mock_driver.reset_mock()
         tmp_lb.amphorae = [AMPS_DATA[0]]

releasenotes/notes/fix-lb-update-with-no-data-abefe7860b8fb4c7.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Fixed an issue where load balancers would go into ERROR when
+    setting data not visible to providers (e.g. tags).