fix: stuck rollout when rollout is paused

Signed-off-by: asingh51 <[email protected]>

rollout/canary.go

@@ -184,7 +184,7 @@ func (c *rolloutContext) scaleDownOldReplicaSetsForCanary(oldRSs []*appsv1.Repli
 
 	annotationedRSs := int32(0)
 	for _, targetRS := range oldRSs {
-		if c.isReplicaSetReferenced(targetRS) {
+		if c.rollout.Spec.Strategy.Canary.TrafficRouting != nil && c.isReplicaSetReferenced(targetRS) {
 			// We might get here if user interrupted an an update in order to move back to stable.
 			c.log.Infof("Skip scale down of older RS '%s': still referenced", targetRS.Name)
 			continue

test/e2e/canary_test.go

@@ -565,6 +565,23 @@ func (s *CanarySuite) TestCanaryScaleDownOnAbortNoTrafficRouting() {
 		ExpectRevisionPodCount("2", 0)
 }
 
+func (s *CanarySuite) TestCanaryWhenRolloutPaused() {
+	s.Given().
+		HealthyRollout(`@functional/canary-deploy-new-rev-on-paused-rollout.yaml`).
+		When().
+		UpdateSpec(). // update to revision 2
+		WaitForRolloutStatus("Paused").
+		UpdateSpec(). // update to revision 3
+		WaitForRolloutStatus("Healthy").
+		Then().
+		// Expect that the canary service selector has been moved back to stable
+		ExpectServiceSelector("canary-next-canary", map[string]string{"app": "canary-next-canary", "rollouts-pod-template-hash": "66597877b7"}, false).
+		When().
+		Sleep(3*time.Second).
+		Then().
+		ExpectRevisionPodCount("2", 0)
+}
+
 func (s *CanarySuite) TestCanaryUnScaleDownOnAbort() {
 	s.Given().
 		HealthyRollout(`@functional/canary-unscaledownonabort.yaml`).

test/e2e/functional/canary-deploy-new-rev-on-paused-rollout.yaml

@@ -0,0 +1,91 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: canary-next-root
+spec:
+  type: NodePort
+  ports:
+    - port: 80
+      targetPort: http
+      protocol: TCP
+      name: http
+  selector:
+    app: canary-next
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: canary-next-canary
+spec:
+  type: NodePort
+  ports:
+    - port: 80
+      targetPort: http
+      protocol: TCP
+      name: http
+  selector:
+    app: canary-next
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: canary-next-stable
+spec:
+  type: NodePort
+  ports:
+    - port: 80
+      targetPort: http
+      protocol: TCP
+      name: http
+  selector:
+    app: canary-next
+---
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: canary-next-ingress
+  annotations:
+    kubernetes.io/ingress.class: alb
+spec:
+  rules:
+    - http:
+        paths:
+          - path: /*
+            pathType: Prefix
+            backend:
+              service:
+                name: canary-next-root
+                port:
+                  name: use-annotation
+---
+apiVersion: argoproj.io/v1alpha1
+kind: Rollout
+metadata:
+  name: canary-scaledownd-on-abort
+spec:
+  selector:
+    matchLabels:
+      app: canary-next
+  template:
+    metadata:
+      labels:
+        app: canary-next
+    spec:
+      containers:
+        - name: canary-next
+          image: nginx:1.19-alpine
+          ports:
+            - name: http
+              containerPort: 80
+              protocol: TCP
+          resources:
+            requests:
+              memory: 16Mi
+              cpu: 5m
+  strategy:
+    canary:
+      canaryService: canary-next-canary
+      stableService: canary-next-stable
+      steps:
+        - setWeight: 50
+        - pause: {}