fix: switch service selector back to stable on canary service when aborted

rollout/trafficrouting.go

@@ -166,6 +166,23 @@ func (c *rolloutContext) reconcileTrafficRouting() error {
 					desiredWeight = minInt(desiredWeight, c.rollout.Status.Canary.Weights.Canary.Weight)
 				}
 			}
+
+			if c.rollout.Spec.Strategy.Canary.DynamicStableScale && desiredWeight == 0 {
+				// If we are using dynamic stable scale we need to also make sure that desiredWeight=0 aka we are completely
+				// done with aborting before resetting the canary service selectors back to stable
+				err = c.ensureSVCTargets(c.rollout.Spec.Strategy.Canary.CanaryService, c.stableRS, true)
+				if err != nil {
+					return err
+				}
+			} else if !c.rollout.Spec.Strategy.Canary.DynamicStableScale {
+				// We are not using dynamic stable scale here, so it is safe to reset the canary service selectors right
+				//away because we will also be immediately setting desiredWeight=0
+				err = c.ensureSVCTargets(c.rollout.Spec.Strategy.Canary.CanaryService, c.stableRS, true)
+				if err != nil {
+					return err
+				}
+			}
+
 			err := reconciler.RemoveManagedRoutes()
 			if err != nil {
 				return err

rollout/trafficrouting_test.go

@@ -893,6 +893,7 @@ func TestDynamicScalingDontIncreaseWeightWhenAborted(t *testing.T) {
 	f.objects = append(f.objects, r2)
 
 	f.expectPatchRolloutAction(r2)
+	f.expectPatchServiceAction(canarySvc, rs1PodHash)
 
 	f.fakeTrafficRouting = newUnmockedFakeTrafficRoutingReconciler()
 	f.fakeTrafficRouting.On("UpdateHash", mock.Anything, mock.Anything, mock.Anything).Return(nil)
@@ -977,3 +978,76 @@ func TestDynamicScalingDecreaseWeightAccordingToStableAvailabilityWhenAborted(t
 	f.fakeTrafficRouting.On("VerifyWeight", mock.Anything).Return(pointer.BoolPtr(true), nil)
 	f.run(getKey(r1, t))
 }
+
+// TestDynamicScalingDecreaseWeightAccordingToStableAvailabilityWhenAbortedAndResetService verifies we decrease the weight
+// to the canary depending on the availability of the stable ReplicaSet when aborting and also that at the end of the abort
+// we reset the canary service selectors back to the stable service
+func TestDynamicScalingDecreaseWeightAccordingToStableAvailabilityWhenAbortedAndResetService(t *testing.T) {
+	f := newFixture(t)
+	defer f.Close()
+
+	steps := []v1alpha1.CanaryStep{
+		{
+			SetWeight: pointer.Int32Ptr(50),
+		},
+		{
+			Pause: &v1alpha1.RolloutPause{},
+		},
+	}
+	r1 := newCanaryRollout("foo", 5, nil, steps, pointer.Int32Ptr(1), intstr.FromInt(1), intstr.FromInt(1))
+	r1.Spec.Strategy.Canary.DynamicStableScale = true
+	r1.Spec.Strategy.Canary.TrafficRouting = &v1alpha1.RolloutTrafficRouting{
+		SMI: &v1alpha1.SMITrafficRouting{},
+	}
+	r1.Spec.Strategy.Canary.CanaryService = "canary"
+	r1.Spec.Strategy.Canary.StableService = "stable"
+	r1.Status.ReadyReplicas = 5
+	r1.Status.AvailableReplicas = 5
+	r1.Status.Abort = true
+	r1.Status.AbortedAt = &metav1.Time{Time: time.Now().Add(-1 * time.Minute)}
+	r2 := bumpVersion(r1)
+
+	rs1 := newReplicaSetWithStatus(r1, 5, 5)
+	rs2 := newReplicaSetWithStatus(r2, 0, 0)
+
+	rs1PodHash := rs1.Labels[v1alpha1.DefaultRolloutUniqueLabelKey]
+	rs2PodHash := rs2.Labels[v1alpha1.DefaultRolloutUniqueLabelKey]
+	canarySelector := map[string]string{v1alpha1.DefaultRolloutUniqueLabelKey: rs2PodHash}
+	stableSelector := map[string]string{v1alpha1.DefaultRolloutUniqueLabelKey: rs1PodHash}
+	canarySvc := newService("canary", 80, canarySelector, r1)
+	stableSvc := newService("stable", 80, stableSelector, r1)
+	r2.Status.StableRS = rs1PodHash
+	r2.Status.Canary.Weights = &v1alpha1.TrafficWeights{
+		Canary: v1alpha1.WeightDestination{
+			Weight:          20,
+			ServiceName:     "canary",
+			PodTemplateHash: rs2PodHash,
+		},
+		Stable: v1alpha1.WeightDestination{
+			Weight:          80,
+			ServiceName:     "stable",
+			PodTemplateHash: rs1PodHash,
+		},
+	}
+
+	f.kubeobjects = append(f.kubeobjects, rs1, rs2, canarySvc, stableSvc)
+	f.replicaSetLister = append(f.replicaSetLister, rs1, rs2)
+
+	f.rolloutLister = append(f.rolloutLister, r2)
+	f.objects = append(f.objects, r2)
+
+	f.expectPatchRolloutAction(r2)
+	f.expectPatchServiceAction(canarySvc, rs1PodHash)
+
+	f.fakeTrafficRouting = newUnmockedFakeTrafficRoutingReconciler()
+	f.fakeTrafficRouting.On("UpdateHash", mock.Anything, mock.Anything, mock.Anything).Return(nil)
+	f.fakeTrafficRouting.On("SetWeight", mock.Anything, mock.Anything).Return(func(desiredWeight int32, additionalDestinations ...v1alpha1.WeightDestination) error {
+		// make sure SetWeight was called with correct value
+		assert.Equal(t, int32(0), desiredWeight)
+		return nil
+	})
+	f.fakeTrafficRouting.On("SetHeaderRoute", mock.Anything, mock.Anything).Return(nil)
+	f.fakeTrafficRouting.On("RemoveManagedRoutes", mock.Anything, mock.Anything).Return(nil)
+	f.fakeTrafficRouting.On("VerifyWeight", mock.Anything).Return(pointer.BoolPtr(true), nil)
+	f.run(getKey(r1, t))
+}

test/e2e/canary_test.go

@@ -538,6 +538,10 @@ func (s *CanarySuite) TestCanaryScaleDownOnAbort() {
 		WaitForRolloutStatus("Paused").
 		AbortRollout().
 		WaitForRolloutStatus("Degraded").
+		Then().
+		//Expect that the canary service selector has been moved back to stable
+		ExpectServiceSelector("canary-scaledowndelay-canary", map[string]string{"app": "canary-scaledowndelay", "rollouts-pod-template-hash": "66597877b7"}, false).
+		When().
 		Sleep(3*time.Second).
 		Then().
 		ExpectRevisionPodCount("2", 0)
@@ -586,9 +590,16 @@ func (s *CanarySuite) TestCanaryDynamicStableScale() {
 		WaitForRevisionPodCount("2", 1).
 		Then().
 		ExpectRevisionPodCount("1", 4).
+		//Assert that the canary service selector is still not set to stable rs because of dynamic stable scale still in progress
+		Assert(func(t *fixtures.Then) {
+			canarySvc, stableSvc := t.GetServices()
+			assert.NotEqual(s.T(), canarySvc.Spec.Selector["rollouts-pod-template-hash"], stableSvc.Spec.Selector["rollouts-pod-template-hash"])
+		}).
 		When().
 		MarkPodsReady("1", 1). // mark last remaining stable pod as ready (4/4 stable are ready)
 		WaitForRevisionPodCount("2", 0).
 		Then().
+		//Expect that the canary service selector is now set to stable because of dynamic stable scale is over and we have all pods up on stable rs
+		ExpectServiceSelector("dynamic-stable-scale-canary", map[string]string{"app": "dynamic-stable-scale", "rollouts-pod-template-hash": "868d98995b"}, false).
 		ExpectRevisionPodCount("1", 4)
 }