add failing test for VS cleanup on delegation

Author: jhuliano

pkg/router/istio_test.go

@@ -599,6 +599,39 @@ func TestIstioRouter_Delegate(t *testing.T) {
 		err := router.Reconcile(mocks.canary)
 		require.Error(t, err)
 	})
+
+	t.Run("syncs when enabled", func(t *testing.T) {
+		mocks := newFixture(nil)
+		mocks.canary.Spec.Service.Hosts = []string{}
+		mocks.canary.Spec.Service.Gateways = []string{}
+		mocks.canary.Spec.Service.PortDiscovery = false
+
+		router := &IstioRouter{
+			logger:        mocks.logger,
+			flaggerClient: mocks.flaggerClient,
+			istioClient:   mocks.meshClient,
+			kubeClient:    mocks.kubeClient,
+		}
+
+		err := router.Reconcile(mocks.canary)
+		require.NoError(t, err)
+
+		vs, err := mocks.meshClient.NetworkingV1beta1().VirtualServices("default").Get(context.TODO(), "podinfo", metav1.GetOptions{})
+		require.NoError(t, err)
+		require.Len(t, vs.Spec.Http, 1)
+		require.Len(t, vs.Spec.Http[0].Route, 2)
+
+		// enable delegation
+		mocks.canary.Spec.Service.Delegation = true
+
+		err = router.Reconcile(mocks.canary)
+		require.NoError(t, err)
+
+		vs, err = mocks.meshClient.NetworkingV1beta1().VirtualServices("default").Get(context.TODO(), "podinfo", metav1.GetOptions{})
+		require.NoError(t, err)
+		assert.Len(t, vs.Spec.Gateways, 0)
+		assert.Len(t, vs.Spec.Hosts, 0)
+	})
 }
 
 func TestIstioRouter_Finalize(t *testing.T) {

test/istio/test-delegation.sh

@@ -52,7 +52,7 @@ spec:
         namespace: test
 EOF
 
-echo '>>> Initialising canary for delegate'
+echo '>>> Initialising canary'
 cat <<EOF | kubectl apply -f -
 apiVersion: flagger.app/v1beta1
 kind: Canary
@@ -68,8 +68,7 @@ spec:
   service:
     port: 80
     targetPort: 9898
-    portDiscovery: true
-    delegation: true
+    delegation: false # start with delegation disabled to make sure it works properly after it's enabled
   analysis:
     interval: 15s
     threshold: 15
@@ -102,6 +101,46 @@ done
 
 echo '✔ Canary initialization test passed'
 
+echo '>>> Enabling delegation on canary'
+kubectl patch canary podinfo -n test --type=merge -p '{"spec":{"service":{"delegation":true}}}'
+
+echo '>>> Waiting for VirtualService to be updated with delegation...'
+
+retries=30
+count=0
+ok=false
+
+until ${ok}; do
+    VS_YAML=$(kubectl get virtualservice/podinfo -n test -o yaml 2>/dev/null)
+
+    # A VirtualService is considered INVALID if it contains a 'hosts:' or 'gateways:' key
+    # that is NOT immediately followed by an empty array '[]'.
+    if [[ -n "${VS_YAML}" ]] && ! echo "${VS_YAML}" | grep -vE '^  (hosts|gateways): \[\]$' | grep -qE '^  (hosts|gateways):'; then
+        echo "✔ Validation Passed: 'gateways' and 'hosts' are either absent or empty."
+        ok=true
+    else
+        # If ok is not true, print a status message.
+        echo "VirtualService not ready yet ('gateways' or 'hosts' key is present). Retrying..."
+        ok=false
+    fi
+
+    if ${ok}; then
+        break
+    fi
+
+    count=$(($count + 1))
+    if [[ ${count} -eq ${retries} ]]; then
+        kubectl -n istio-system logs deployment/flagger
+        kubectl get virtualservice/podinfo -n test -o yaml
+        echo "No more retries left"
+        exit 1
+    fi
+
+    sleep 5
+done
+
+echo '✔ VirtualService delegation enabled'
+
 echo '>>> Triggering canary deployment'
 kubectl -n test set image deployment/podinfo podinfod=ghcr.io/stefanprodan/podinfo:6.0.1