From f12325add3fbac8a2ce31cb12b4649c01d74f248 Mon Sep 17 00:00:00 2001
From: danishprakash <grafitykoncept@gmail.com>
Date: Tue, 14 Jun 2022 10:42:03 +0530
Subject: [PATCH] pkg/admission/storageclass: pick random storageclass if >1
 present

Signed-off-by: danishprakash <grafitykoncept@gmail.com>
---
 pkg/volume/util/storageclass.go               | 15 ++++--
 .../storageclass/setdefault/admission.go      |  1 +
 .../storageclass/setdefault/admission_test.go | 46 ++++++++++++++++---
 3 files changed, 51 insertions(+), 11 deletions(-)

diff --git a/pkg/volume/util/storageclass.go b/pkg/volume/util/storageclass.go
index 5350bc8e963..fd1e9c4fddf 100644
--- a/pkg/volume/util/storageclass.go
+++ b/pkg/volume/util/storageclass.go
@@ -17,9 +17,9 @@ limitations under the License.
 package util
 
 import (
-	"fmt"
+	"sort"
+
 	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"
@@ -54,10 +54,17 @@ func GetDefaultClass(lister storagev1listers.StorageClassLister) (*storagev1.Sto
 	if len(defaultClasses) == 0 {
 		return nil, nil
 	}
+
+	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()
+	})
 	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)))
+		klog.V(4).Infof("%d default StorageClasses were found, choosing the newest: %s", len(defaultClasses), defaultClasses[0].Name)
 	}
+
 	return defaultClasses[0], nil
 }
 
diff --git a/plugin/pkg/admission/storage/storageclass/setdefault/admission.go b/plugin/pkg/admission/storage/storageclass/setdefault/admission.go
index aa4c1c14ba7..4772996a1a7 100644
--- a/plugin/pkg/admission/storage/storageclass/setdefault/admission.go
+++ b/plugin/pkg/admission/storage/storageclass/setdefault/admission.go
@@ -20,6 +20,7 @@ import (
 	"context"
 	"fmt"
 	"io"
+
 	"k8s.io/kubernetes/pkg/volume/util"
 
 	"k8s.io/klog/v2"
diff --git a/plugin/pkg/admission/storage/storageclass/setdefault/admission_test.go b/plugin/pkg/admission/storage/storageclass/setdefault/admission_test.go
index da48d69e7d0..9883fd97e0b 100644
--- a/plugin/pkg/admission/storage/storageclass/setdefault/admission_test.go
+++ b/plugin/pkg/admission/storage/storageclass/setdefault/admission_test.go
@@ -19,6 +19,7 @@ package setdefault
 import (
 	"context"
 	"testing"
+	"time"
 
 	"k8s.io/klog/v2"
 
@@ -96,6 +97,30 @@ func TestAdmission(t *testing.T) {
 		},
 		Provisioner: "nondefault1",
 	}
+	classWithCreateTime1 := &storagev1.StorageClass{
+		TypeMeta: metav1.TypeMeta{
+			Kind: "StorageClass",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:              "default1",
+			CreationTimestamp: metav1.NewTime(time.Date(2022, time.Month(1), 1, 0, 0, 0, 1, time.UTC)),
+			Annotations: map[string]string{
+				storageutil.IsDefaultStorageClassAnnotation: "true",
+			},
+		},
+	}
+	classWithCreateTime2 := &storagev1.StorageClass{
+		TypeMeta: metav1.TypeMeta{
+			Kind: "StorageClass",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:              "default2",
+			CreationTimestamp: metav1.NewTime(time.Date(2022, time.Month(1), 1, 0, 0, 0, 0, time.UTC)),
+			Annotations: map[string]string{
+				storageutil.IsDefaultStorageClassAnnotation: "true",
+			},
+		},
+	}
 
 	claimWithClass := &api.PersistentVolumeClaim{
 		TypeMeta: metav1.TypeMeta{
@@ -166,13 +191,6 @@ func TestAdmission(t *testing.T) {
 			false,
 			"foo",
 		},
-		{
-			"two defaults, error with PVC with class=nil",
-			[]*storagev1.StorageClass{defaultClass1, defaultClass2, classWithFalseDefault, classWithNoDefault, classWithEmptyDefault},
-			claimWithNoClass,
-			true,
-			"",
-		},
 		{
 			"two defaults, no modification of PVC with class=''",
 			[]*storagev1.StorageClass{defaultClass1, defaultClass2, classWithFalseDefault, classWithNoDefault, classWithEmptyDefault},
@@ -187,6 +205,20 @@ func TestAdmission(t *testing.T) {
 			false,
 			"foo",
 		},
+		{
+			"two defaults with same creation time, choose the one with smaller name",
+			[]*storagev1.StorageClass{defaultClass1, defaultClass2, classWithFalseDefault, classWithNoDefault, classWithEmptyDefault},
+			claimWithNoClass,
+			false,
+			defaultClass1.Name,
+		},
+		{
+			"two defaults, choose the one with newer creation time",
+			[]*storagev1.StorageClass{classWithCreateTime1, classWithCreateTime2, classWithFalseDefault, classWithNoDefault, classWithEmptyDefault},
+			claimWithNoClass,
+			false,
+			classWithCreateTime1.Name,
+		},
 	}
 
 	for _, test := range tests {