feature flag and wait for resize

kubernetes · Dec 7, 2018 · 0a2c2b0 · 0a2c2b0
1 parent 57d1406
commit 0a2c2b0
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Showing 3 changed files with 34 additions and 11 deletions.
diff --git a/pkg/apis/apps/validation/validation.go b/pkg/apis/apps/validation/validation.go
@@ -28,9 +28,11 @@ import (
 	"k8s.io/apimachinery/pkg/util/intstr"
 	"k8s.io/apimachinery/pkg/util/validation"
 	"k8s.io/apimachinery/pkg/util/validation/field"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/kubernetes/pkg/apis/apps"
 	api "k8s.io/kubernetes/pkg/apis/core"
 	apivalidation "k8s.io/kubernetes/pkg/apis/core/validation"
+	"k8s.io/kubernetes/pkg/features"
 )
 
 // ValidateStatefulSetName can be used to check whether the given StatefulSet name is valid.
@@ -154,21 +156,30 @@ func ValidateStatefulSetUpdate(statefulSet, oldStatefulSet *apps.StatefulSet) fi
 	statefulSet.Spec.UpdateStrategy = oldStatefulSet.Spec.UpdateStrategy
 
 	restoreVolumeClaimTemplates := make([]api.PersistentVolumeClaim, len(statefulSet.Spec.VolumeClaimTemplates))
+	volumeExpansionEnabled := utilfeature.DefaultFeatureGate.Enabled(features.ExpandPersistentVolumes)
 	if len(oldStatefulSet.Spec.VolumeClaimTemplates) == len(statefulSet.Spec.VolumeClaimTemplates) {
 		for index, oldVolumeClaimTemplate := range oldStatefulSet.Spec.VolumeClaimTemplates {
-			oldStorageRequest := oldVolumeClaimTemplate.Spec.Resources.Requests[api.ResourceStorage]
-			newStorageRequest := statefulSet.Spec.VolumeClaimTemplates[index].Spec.Resources.Requests[api.ResourceStorage]
-			if newStorageRequest.Cmp(oldStorageRequest) < 0 {
-				allErrs = append(allErrs, field.Forbidden(field.NewPath("spec", "volumeClaimTemplates", fmt.Sprint(index), "spec", "resources", "requests", "storage"), "storage request can not be less than previous value"))
-			}
-
 			restoreVolumeClaimTemplates[index] = *statefulSet.Spec.VolumeClaimTemplates[index].DeepCopy()
-			statefulSet.Spec.VolumeClaimTemplates[index].Spec.Resources.Requests[api.ResourceStorage] = oldStorageRequest
+			if volumeExpansionEnabled {
+				oldStorageRequest := oldVolumeClaimTemplate.Spec.Resources.Requests[api.ResourceStorage]
+				newStorageRequest := statefulSet.Spec.VolumeClaimTemplates[index].Spec.Resources.Requests[api.ResourceStorage]
+				if newStorageRequest.Cmp(oldStorageRequest) < 0 {
+					allErrs = append(allErrs, field.Forbidden(field.NewPath("spec", "volumeClaimTemplates", fmt.Sprint(index), "spec", "resources", "requests", "storage"), "storage request can not be less than previous value"))
+				}
+				statefulSet.Spec.VolumeClaimTemplates[index].Spec.Resources.Requests[api.ResourceStorage] = oldStorageRequest
+			}
 		}
 	}
 
 	if !apiequality.Semantic.DeepEqual(statefulSet.Spec, oldStatefulSet.Spec) {
-		allErrs = append(allErrs, field.Forbidden(field.NewPath("spec"), "updates to statefulset spec for fields other than 'replicas', 'template' ,'updateStrategy' and 'volumeClaimTemplate.Spec.Resources.Requests[storage]' are forbidden"))
+		var errMsg string
+		if volumeExpansionEnabled {
+			errMsg = "updates to statefulset spec for fields other than 'replicas', 'template', 'updateStrategy' and 'volumeClaimTemplate.Spec.Resources.Requests[storage]' are forbidden"
+		} else {
+			errMsg = "updates to statefulset spec for fields other than 'replicas', 'template' and 'updateStrategy' are forbidden"
+		}
+
+		allErrs = append(allErrs, field.Forbidden(field.NewPath("spec"), errMsg))
 	}
 	statefulSet.Spec.Replicas = restoreReplicas
 	statefulSet.Spec.Template = restoreTemplate

diff --git a/pkg/controller/statefulset/stateful_pod_control.go b/pkg/controller/statefulset/stateful_pod_control.go
@@ -217,14 +217,17 @@ func (spc *realStatefulPodControl) updatePersistentVolumeClaims(set *apps.Statef
 
 		currentStorageRequest := currentClaim.Spec.Resources.Requests[v1.ResourceStorage]
 		updatedStorageRequest := updatedClaim.Spec.Resources.Requests[v1.ResourceStorage]
-		if updatedStorageRequest.Cmp(currentStorageRequest) != 0 {
+		if updatedStorageRequest.Cmp(currentStorageRequest) > 0 {
 			currentClaim.Spec.Resources.Requests[v1.ResourceStorage] = updatedStorageRequest
-			_, err = spc.client.CoreV1().PersistentVolumeClaims(currentClaim.Namespace).Update(currentClaim)
+			currentClaim, err = spc.client.CoreV1().PersistentVolumeClaims(currentClaim.Namespace).Update(currentClaim)
 			if err != nil {
 				errs = append(errs, fmt.Errorf("Failed to update PVC %s: %s", currentClaim.Name, err))
 				spc.recordClaimEvent("update", set, pod, currentClaim, err)
 			}
-			// Add wait for the FileSystemResizePending condition? So pods are restarted after underlying volume has expanded
+		}
+
+		if !resizePending(currentClaim) {
+			errs = append(errs, fmt.Errorf("Controller resize pending for PVC %s", currentClaim.Name))
 		}
 	}
 	return errorutils.NewAggregate(errs)

diff --git a/pkg/controller/statefulset/stateful_set_utils.go b/pkg/controller/statefulset/stateful_set_utils.go
@@ -236,6 +236,15 @@ func isHealthy(pod *v1.Pod) bool {
 	return isRunningAndReady(pod) && !isTerminating(pod)
 }
 
+func resizePending(pvc *v1.PersistentVolumeClaim) bool {
+	for _, condition := range pvc.Status.Conditions {
+		if condition.Type == v1.PersistentVolumeClaimFileSystemResizePending && condition.Status == v1.ConditionTrue {
+			return true
+		}
+	}
+	return false
+}
+
 // allowsBurst is true if the alpha burst annotation is set.
 func allowsBurst(set *apps.StatefulSet) bool {
 	return set.Spec.PodManagementPolicy == apps.ParallelPodManagement