Merge pull request #50924 from liggitt/alpha-fields

Automatic merge from submit-queue (batch tested with PRs 51682, 51546, 51369, 50924, 51827)

Clear values for disabled alpha fields

Fixes #51831

Before persisting new or updated resources, alpha fields that are disabled by feature gate must be removed from the incoming objects.

This adds a helper for clearing these values for pod specs and calls it from the strategies of all in-tree resources containing pod specs.

Addresses https://github.com/kubernetes/community/pull/869

pkg/api/pod/BUILD

@@ -11,7 +11,9 @@ go_library(
     srcs = ["util.go"],
     deps = [
         "//pkg/api:go_default_library",
+        "//pkg/features:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/util/feature:go_default_library",
     ],
 )
 

pkg/api/pod/util.go

@@ -18,7 +18,9 @@ package pod
 
 import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/features"
 )
 
 // Visitor is called with each object name, and returns true if visiting should continue
@@ -225,3 +227,20 @@ func UpdatePodCondition(status *api.PodStatus, condition *api.PodCondition) bool
 	// Return true if one of the fields have changed.
 	return !isEqual
 }
+
+// DropDisabledAlphaFields removes disabled fields from the pod spec.
+// This should be called from PrepareForCreate/PrepareForUpdate for all resources containing a pod spec.
+func DropDisabledAlphaFields(podSpec *api.PodSpec) {
+	if !utilfeature.DefaultFeatureGate.Enabled(features.PodPriority) {
+		podSpec.Priority = nil
+		podSpec.PriorityClassName = ""
+	}
+
+	if !utilfeature.DefaultFeatureGate.Enabled(features.LocalStorageCapacityIsolation) {
+		for i := range podSpec.Volumes {
+			if podSpec.Volumes[i].EmptyDir != nil {
+				podSpec.Volumes[i].EmptyDir.SizeLimit = nil
+			}
+		}
+	}
+}