fix finalizer removal logic for ingresses

pkg/controllers/ingress/ingress.go

@@ -196,12 +196,24 @@ func (c *Controller) sync(key string) error {
 
 	ingressClass, err := util.GetIngressClass(ingress, c.ingressClassLister)
 	if err != nil {
+		deleteFinalizerErr := c.deleteFinalizer(ingress)
+		if deleteFinalizerErr != nil {
+			return fmt.Errorf("got error %w while getting IngressClass for Ingress %s/%s. Unable to delete finalizer "+
+				"%s due to error: %s", err, ingress.Namespace, ingress.Name, util.IngressControllerFinalizer, deleteFinalizerErr.Error())
+		}
+
 		return err
 	}
 
 	if ingressClass == nil || ingressClass.Spec.Controller != c.controllerClass {
 		klog.V(4).InfoS("skipping ingress class, not for this controller", "ingress", klog.KRef(namespace, name))
-		// skipping since ingress class is not applicable to this controller
+		// skipping since ingress class is not applicable to this controller, we remove our finalizer if it exists
+		deleteFinalizerErr := c.deleteFinalizer(ingress)
+		if deleteFinalizerErr != nil {
+			klog.V(4).Infof("Found Ingress %s/%s with finalizer %s, but not managed by this controller. Unable to delete"+
+				" finalizer due to error: %s", ingress.Namespace, ingress.Name, util.IngressControllerFinalizer, deleteFinalizerErr.Error())
+		}
+
 		return nil
 	}
 

pkg/util/util.go

@@ -336,6 +336,7 @@ func GetIngressClass(ingress *networkingv1.Ingress, ingressClassLister networkin
 			}
 		}
 
+		klog.V(4).Infof("no IngressClassName set for %s, and no default IngressClass found", ingress.Name)
 		return nil, nil
 	}
 
@@ -345,7 +346,8 @@ func GetIngressClass(ingress *networkingv1.Ingress, ingressClassLister networkin
 		}
 	}
 
-	return nil, errors.New("ingress class not found for ingress")
+	klog.V(4).Infof("for Ingress %s, set IngressClass %s not found", ingress.Name, *ingress.Spec.IngressClassName)
+	return nil, nil
 }
 
 func PathToServiceAndPort(ingressNamespace string, path networkingv1.HTTPIngressPath, serviceLister corelisters.ServiceLister) (string, int32, error) {

pkg/util/util_test.go

@@ -13,6 +13,7 @@ import (
 	"fmt"
 	"k8s.io/apimachinery/pkg/util/sets"
 	corelisters "k8s.io/client-go/listers/core/v1"
+	networkingListers "k8s.io/client-go/listers/networking/v1"
 	"strings"
 	"testing"
 
@@ -463,27 +464,10 @@ func TestGetPodReadinessCondition(t *testing.T) {
 
 func TestGetIngressClass(t *testing.T) {
 	RegisterTestingT(t)
-	client := fakeclientset.NewSimpleClientset()
-
-	ingressClassList := getIngressClassList()
-
-	client.NetworkingV1().(*fake2.FakeNetworkingV1).
-		PrependReactor("list", "ingressclasses", func(action k8stesting.Action) (handled bool, ret runtime.Object, err error) {
-			return true, ingressClassList, nil
-		})
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
 
-	informerFactory := informers.NewSharedInformerFactory(client, 0)
-	ingressClassInformer := informerFactory.Networking().V1().IngressClasses()
-	ingressClassLister := ingressClassInformer.Lister()
-
-	informerFactory.Start(ctx.Done())
-	cache.WaitForCacheSync(ctx.Done(), ingressClassInformer.Informer().HasSynced)
+	ingressClassLister := getIngressClassLister(getIngressClassList())
 
 	ingressClassName := "ingress-class"
-
 	i := networkingv1.Ingress{
 		TypeMeta: metav1.TypeMeta{},
 		Spec: networkingv1.IngressSpec{
@@ -502,7 +486,34 @@ func TestGetIngressClass(t *testing.T) {
 
 	i.Spec.IngressClassName = common.String("unknownIngress")
 	ic, err = GetIngressClass(&i, ingressClassLister)
-	Expect(err).To(HaveOccurred())
+	Expect(err).NotTo(HaveOccurred())
+	Expect(ic).To(BeNil())
+
+	ingressClassLister = getIngressClassLister(&networkingv1.IngressClassList{Items: []networkingv1.IngressClass{}})
+
+	i.Spec.IngressClassName = nil
+	ic, err = GetIngressClass(&i, ingressClassLister)
+	Expect(err).ToNot(HaveOccurred())
+	Expect(ic).To(BeNil())
+}
+
+func getIngressClassLister(ingressClassList *networkingv1.IngressClassList) networkingListers.IngressClassLister {
+	client := fakeclientset.NewSimpleClientset()
+
+	client.NetworkingV1().(*fake2.FakeNetworkingV1).
+		PrependReactor("list", "ingressclasses", func(action k8stesting.Action) (handled bool, ret runtime.Object, err error) {
+			return true, ingressClassList, nil
+		})
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	informerFactory := informers.NewSharedInformerFactory(client, 0)
+	ingressClassInformer := informerFactory.Networking().V1().IngressClasses()
+	ingressClassLister := ingressClassInformer.Lister()
+	informerFactory.Start(ctx.Done())
+	cache.WaitForCacheSync(ctx.Done(), ingressClassInformer.Informer().HasSynced)
+	return ingressClassLister
 }
 
 func TestGetHealthChecker(t *testing.T) {