kubeadm: Amend the hyperkube deprecation change

The PR introducing 5bb8069 got merged accidentally (the CI robot not
respecting a hold). Hence, the feedback to that PR is merged separately.

Signed-off-by: Rostislav M. Georgiev <[email protected]>

Author: rosti

cmd/kubeadm/app/apis/kubeadm/types.go

@@ -114,6 +114,8 @@ type ClusterConfiguration struct {
 	CIImageRepository string
 
 	// UseHyperKubeImage controls if hyperkube should be used for Kubernetes components instead of their respective separate images
+	// DEPRECATED: As hyperkube is itself deprecated, this fields is too. It will be removed in future kubeadm config versions, kubeadm
+	// will print multiple warnings when set to true, and at some point it may become ignored.
 	UseHyperKubeImage bool
 
 	// FeatureGates enabled by the user.

cmd/kubeadm/app/apis/kubeadm/v1beta1/types.go

@@ -17,7 +17,7 @@ limitations under the License.
 package v1beta1
 
 import (
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
@@ -106,6 +106,8 @@ type ClusterConfiguration struct {
 	ImageRepository string `json:"imageRepository"`
 
 	// UseHyperKubeImage controls if hyperkube should be used for Kubernetes components instead of their respective separate images
+	// DEPRECATED: As hyperkube is itself deprecated, this fields is too. It will be removed in future kubeadm config versions, kubeadm
+	// will print multiple warnings when set to true, and at some point it may become ignored.
 	UseHyperKubeImage bool `json:"useHyperKubeImage,omitempty"`
 
 	// FeatureGates enabled by the user.

cmd/kubeadm/app/apis/kubeadm/v1beta2/types.go

@@ -17,7 +17,7 @@ limitations under the License.
 package v1beta2
 
 import (
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
@@ -102,6 +102,8 @@ type ClusterConfiguration struct {
 	ImageRepository string `json:"imageRepository,omitempty"`
 
 	// UseHyperKubeImage controls if hyperkube should be used for Kubernetes components instead of their respective separate images
+	// DEPRECATED: As hyperkube is itself deprecated, this fields is too. It will be removed in future kubeadm config versions, kubeadm
+	// will print multiple warnings when set to true, and at some point it may become ignored.
 	UseHyperKubeImage bool `json:"useHyperKubeImage,omitempty"`
 
 	// FeatureGates enabled by the user.

cmd/kubeadm/app/images/images.go

@@ -25,6 +25,8 @@ import (
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 )
 
+const extraHyperKubeNote = ` The "useHyperKubeImage" field will be removed from future kubeadm config versions and possibly ignored in future releases.`
+
 // GetGenericImage generates and returns a platform agnostic image (backed by manifest list)
 func GetGenericImage(prefix, image, tag string) string {
 	return fmt.Sprintf("%s/%s:%s", prefix, image, tag)
@@ -34,7 +36,7 @@ func GetGenericImage(prefix, image, tag string) string {
 // including the control-plane components and kube-proxy. If specified, the HyperKube image will be used.
 func GetKubernetesImage(image string, cfg *kubeadmapi.ClusterConfiguration) string {
 	if cfg.UseHyperKubeImage && image != constants.HyperKube {
-		klog.Warningf(`WARNING: DEPRECATED use of the "hyperkube" image in place of %q`, image)
+		klog.Warningf(`WARNING: DEPRECATED use of the "hyperkube" image in place of %q.`+extraHyperKubeNote, image)
 		image = constants.HyperKube
 	}
 	repoPrefix := cfg.GetControlPlaneImageRepository()
@@ -93,7 +95,7 @@ func GetControlPlaneImages(cfg *kubeadmapi.ClusterConfiguration) []string {
 
 	// start with core kubernetes images
 	if cfg.UseHyperKubeImage {
-		klog.Warningln(`WARNING: DEPRECATED use of the "hyperkube" image for the Kubernetes control plane`)
+		klog.Warningln(`WARNING: DEPRECATED use of the "hyperkube" image for the Kubernetes control plane.` + extraHyperKubeNote)
 		imgs = append(imgs, GetKubernetesImage(constants.HyperKube, cfg))
 	} else {
 		imgs = append(imgs, GetKubernetesImage(constants.KubeAPIServer, cfg))