move storage class helpers to utils

pkg/volume/util/storageclass.go

@@ -0,0 +1,76 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+import (
+	"fmt"
+	storagev1 "k8s.io/api/storage/v1"
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
+	storagev1listers "k8s.io/client-go/listers/storage/v1"
+	"k8s.io/klog/v2"
+)
+
+const (
+	// isDefaultStorageClassAnnotation represents a StorageClass annotation that
+	// marks a class as the default StorageClass
+	IsDefaultStorageClassAnnotation = "storageclass.kubernetes.io/is-default-class"
+
+	// betaIsDefaultStorageClassAnnotation is the beta version of IsDefaultStorageClassAnnotation.
+	// TODO: remove Beta when no longer used
+	BetaIsDefaultStorageClassAnnotation = "storageclass.beta.kubernetes.io/is-default-class"
+)
+
+// GetDefaultClass returns the default StorageClass from the store, or nil.
+func GetDefaultClass(lister storagev1listers.StorageClassLister) (*storagev1.StorageClass, error) {
+	list, err := lister.List(labels.Everything())
+	if err != nil {
+		return nil, err
+	}
+
+	defaultClasses := []*storagev1.StorageClass{}
+	for _, class := range list {
+		if IsDefaultAnnotation(class.ObjectMeta) {
+			defaultClasses = append(defaultClasses, class)
+			klog.V(4).Infof("GetDefaultClass added: %s", class.Name)
+		}
+	}
+
+	if len(defaultClasses) == 0 {
+		return nil, nil
+	}
+	if len(defaultClasses) > 1 {
+		klog.V(4).Infof("GetDefaultClass %d defaults found", len(defaultClasses))
+		return nil, errors.NewInternalError(fmt.Errorf("%d default StorageClasses were found", len(defaultClasses)))
+	}
+	return defaultClasses[0], nil
+}
+
+// IsDefaultAnnotation returns a boolean if the default storage class
+// annotation is set
+// TODO: remove Beta when no longer needed
+func IsDefaultAnnotation(obj metav1.ObjectMeta) bool {
+	if obj.Annotations[IsDefaultStorageClassAnnotation] == "true" {
+		return true
+	}
+	if obj.Annotations[BetaIsDefaultStorageClassAnnotation] == "true" {
+		return true
+	}
+
+	return false
+}