feat(vi-vd): get newest default StorageClass (#499)

Description
Align the method for getting the default StorageClass with how the default StorageClass is defined in k8s

Why do we need it, and what problem does it solve?
Currently if there are multiple default StorageClasses, we take the random one, the behavior in k8s is different, the last annotated default StorageClass is taken

What is the expected result?
Take the last annotated default StorageClass

images/virtualization-artifact/pkg/controller/service/disk_service.go

@@ -22,6 +22,7 @@ import (
 	"errors"
 	"fmt"
 	"slices"
+	"sort"
 	"strconv"
 	"strings"
 
@@ -509,13 +510,27 @@ func (s DiskService) getDefaultStorageClass(ctx context.Context) (*storev1.Stora
 		return nil, err
 	}
 
-	for _, sc := range scs.Items {
-		if sc.Annotations[common.AnnDefaultStorageClass] == "true" {
-			return &sc, nil
+	var defaultClasses []*storev1.StorageClass
+	for idx := range scs.Items {
+		if scs.Items[idx].Annotations[common.AnnDefaultStorageClass] == "true" {
+			defaultClasses = append(defaultClasses, &scs.Items[idx])
 		}
 	}
 
-	return nil, ErrDefaultStorageClassNotFound
+	if len(defaultClasses) == 0 {
+		return nil, ErrDefaultStorageClassNotFound
+	}
+
+	// Primary sort by creation timestamp, newest first
+	// Secondary sort by class name, ascending order
+	sort.Slice(defaultClasses, func(i, j int) bool {
+		if defaultClasses[i].CreationTimestamp.UnixNano() == defaultClasses[j].CreationTimestamp.UnixNano() {
+			return defaultClasses[i].Name < defaultClasses[j].Name
+		}
+		return defaultClasses[i].CreationTimestamp.UnixNano() > defaultClasses[j].CreationTimestamp.UnixNano()
+	})
+
+	return defaultClasses[0], nil
 }
 
 func (s DiskService) getStorageClass(ctx context.Context, storageClassName string) (*storev1.StorageClass, error) {

tests/e2e/util_test.go

@@ -23,6 +23,7 @@ import (
 	"net"
 	"net/netip"
 	"os"
+	"sort"
 	"strings"
 	"time"
 
@@ -251,14 +252,27 @@ func GetDefaultStorageClass() (*storagev1.StorageClass, error) {
 		return nil, err
 	}
 
-	for _, sc := range scList.Items {
-		isDefault, ok := sc.Annotations["storageclass.kubernetes.io/is-default-class"]
-		if ok && isDefault == "true" {
-			return &sc, nil
+	var defaultClasses []*storagev1.StorageClass
+	for idx := range scList.Items {
+		if scList.Items[idx].Annotations["storageclass.kubernetes.io/is-default-class"] == "true" {
+			defaultClasses = append(defaultClasses, &scList.Items[idx])
 		}
 	}
 
-	return nil, fmt.Errorf("Default StorageClass not found in the cluster: please set a default StorageClass.")
+	if len(defaultClasses) == 0 {
+		return nil, fmt.Errorf("Default StorageClass not found in the cluster: please set a default StorageClass.")
+	}
+
+	// Primary sort by creation timestamp, newest first
+	// Secondary sort by class name, ascending order
+	sort.Slice(defaultClasses, func(i, j int) bool {
+		if defaultClasses[i].CreationTimestamp.UnixNano() == defaultClasses[j].CreationTimestamp.UnixNano() {
+			return defaultClasses[i].Name < defaultClasses[j].Name
+		}
+		return defaultClasses[i].CreationTimestamp.UnixNano() > defaultClasses[j].CreationTimestamp.UnixNano()
+	})
+
+	return defaultClasses[0], nil
 }
 
 func toIPNet(prefix netip.Prefix) *net.IPNet {