Migrate ingress.class annotation to new IngressClassName field

cmd/nginx/flags.go

@@ -59,8 +59,8 @@ requests to the first port of this Service.`)
 
 		ingressClass = flags.String("ingress-class", "",
 			`Name of the ingress class this controller satisfies.
-The class of an Ingress object is set using the annotation "kubernetes.io/ingress.class".
-All ingress classes are satisfied if this parameter is left empty.`)
+The class of an Ingress object is set using the field IngressClassName in Kubernetes clusters version v1.18.0 or higher or the annotation "kubernetes.io/ingress.class" (deprecated).
+All ingress classes are satisfied if this parameter is not set.`)
 
 		configMap = flags.String("configmap", "",
 			`Name of the ConfigMap containing custom global configurations for the controller.`)

cmd/nginx/main.go

@@ -102,11 +102,15 @@ func main() {
 	conf.FakeCertificate = ssl.GetFakeSSLCert()
 	klog.Infof("SSL fake certificate created %v", conf.FakeCertificate.PemFileName)
 
-	k8s.IsNetworkingIngressAvailable = k8s.NetworkingIngressAvailable(kubeClient)
+	k8s.IsNetworkingIngressAvailable, k8s.IsIngressV1Ready = k8s.NetworkingIngressAvailable(kubeClient)
 	if !k8s.IsNetworkingIngressAvailable {
 		klog.Warningf("Using deprecated \"k8s.io/api/extensions/v1beta1\" package because Kubernetes version is < v1.14.0")
 	}
 
+	if !k8s.IsIngressV1Ready {
+		klog.Infof("Enabling new Ingress features availables since v1.18.0")
+	}
+
 	conf.Client = kubeClient
 
 	reg := prometheus.NewRegistry()

internal/ingress/annotations/class/main.go

@@ -17,8 +17,6 @@ limitations under the License.
 package class
 
 import (
-	"k8s.io/klog"
-
 	networking "k8s.io/api/networking/v1beta1"
 )
 
@@ -43,10 +41,7 @@ var (
 // the ingress.class annotation, or it's set to the configured in the
 // ingress controller.
 func IsValid(ing *networking.Ingress) bool {
-	ingress, ok := ing.GetAnnotations()[IngressKey]
-	if !ok {
-		klog.V(3).Infof("annotation %v is not present in ingress %v/%v", IngressKey, ing.Namespace, ing.Name)
-	}
+	className := ing.Spec.IngressClassName
 
 	// we have 2 valid combinations
 	// 1 - ingress with default class | blank annotation on ingress
@@ -55,9 +50,17 @@ func IsValid(ing *networking.Ingress) bool {
 	// and 2 invalid combinations
 	// 3 - ingress with default class | fixed annotation on ingress
 	// 4 - ingress with specific class | different annotation on ingress
-	if ingress == "" && IngressClass == DefaultClass {
+	if className != nil {
+		return *className == IngressClass
+	}
+
+	if IngressClass == DefaultClass {
 		return true
 	}
 
-	return ingress == IngressClass
+	if IngressClass == "" {
+		return true
+	}
+
+	return false
 }

internal/ingress/annotations/class/main_test.go

@@ -54,10 +54,10 @@ func TestIsValidClass(t *testing.T) {
 		},
 	}
 
-	data := map[string]string{}
-	ing.SetAnnotations(data)
 	for _, test := range tests {
-		ing.Annotations[IngressKey] = test.ingress
+		if test.ingress != "" {
+			ing.Spec.IngressClassName = &test.ingress
+		}
 
 		IngressClass = test.controller
 		DefaultClass = test.defClass

internal/ingress/controller/controller_test.go

@@ -190,7 +190,8 @@ func TestCheckIngress(t *testing.T) {
 	}
 
 	t.Run("When the ingress class differs from nginx", func(t *testing.T) {
-		ing.ObjectMeta.Annotations["kubernetes.io/ingress.class"] = "different"
+		class := "different"
+		ing.Spec.IngressClassName = &class
 		nginx.command = testNginxTestCommand{
 			t:   t,
 			err: fmt.Errorf("test error"),
@@ -201,7 +202,8 @@ func TestCheckIngress(t *testing.T) {
 	})
 
 	t.Run("when the class is the nginx one", func(t *testing.T) {
-		ing.ObjectMeta.Annotations["kubernetes.io/ingress.class"] = "nginx"
+		class := "nginx"
+		ing.Spec.IngressClassName = &class
 		nginx.command = testNginxTestCommand{
 			t:        t,
 			err:      nil,

internal/ingress/controller/store/store.go

@@ -949,12 +949,22 @@ func toIngress(obj interface{}) (*networkingv1beta1.Ingress, bool) {
 			return nil, false
 		}
 
+		ing.Spec.IngressClassName = extractClassName(ing)
 		return ing, true
 	}
 
 	if ing, ok := obj.(*networkingv1beta1.Ingress); ok {
+		ing.Spec.IngressClassName = extractClassName(ing)
 		return ing, true
 	}
 
 	return nil, false
 }
+
+func extractClassName(ing *networkingv1beta1.Ingress) *string {
+	if c, ok := ing.Annotations[class.IngressKey]; ok {
+		return &c
+	}
+
+	return nil
+}

internal/k8s/main.go

@@ -118,26 +118,26 @@ func MetaNamespaceKey(obj interface{}) string {
 // IsNetworkingIngressAvailable indicates if package "k8s.io/api/networking/v1beta1" is available or not
 var IsNetworkingIngressAvailable bool
 
-// NetworkingIngressAvailable checks if the package "k8s.io/api/networking/v1beta1" is available or not
-func NetworkingIngressAvailable(client clientset.Interface) bool {
+// IsIngressV1Ready indicates if the running Kubernetes version is at least v1.18.0
+var IsIngressV1Ready bool
+
+// NetworkingIngressAvailable checks if the package "k8s.io/api/networking/v1beta1"
+// is available or not and if Ingress V1 is supported (k8s >= v1.18.0)
+func NetworkingIngressAvailable(client clientset.Interface) (bool, bool) {
 	// check kubernetes version to use new ingress package or not
-	version114, err := version.ParseGeneric("v1.14.0")
-	if err != nil {
-		klog.Errorf("unexpected error parsing version: %v", err)
-		return false
-	}
+	version114, _ := version.ParseGeneric("v1.14.0")
+	version118, _ := version.ParseGeneric("v1.18.0")
 
 	serverVersion, err := client.Discovery().ServerVersion()
 	if err != nil {
-		klog.Errorf("unexpected error parsing Kubernetes version: %v", err)
-		return false
+		return false, false
 	}
 
 	runningVersion, err := version.ParseGeneric(serverVersion.String())
 	if err != nil {
 		klog.Errorf("unexpected error parsing running Kubernetes version: %v", err)
-		return false
+		return false, false
 	}
 
-	return runningVersion.AtLeast(version114)
+	return runningVersion.AtLeast(version114), runningVersion.AtLeast(version118)
 }