Use Patch operation for PV updates

Author: chethanv28

pkg/csi/service/common/commonco/k8sorchestrator/k8sorchestrator.go

@@ -19,6 +19,7 @@ package k8sorchestrator
 import (
 	"context"
 	"crypto/sha256"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"os"
@@ -44,6 +45,7 @@ import (
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
 	k8stypes "k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/util/strategicpatch"
 	"k8s.io/client-go/informers"
 	clientset "k8s.io/client-go/kubernetes"
 	restclient "k8s.io/client-go/rest"
@@ -2229,11 +2231,36 @@ func (c *K8sOrchestrator) UpdatePersistentVolumeLabel(ctx context.Context,
 		if err != nil {
 			return fmt.Errorf("error getting PV %s from API server: %w", pvName, err)
 		}
-		if pv.Labels == nil {
-			pv.Labels = make(map[string]string)
+
+		oldData, err := json.Marshal(pv)
+		if err != nil {
+			errMsg := fmt.Sprintf("Failed to marshal PV %s: %v", pvName, err)
+			log.Error(errMsg)
+			return err
 		}
-		pv.Labels[key] = value
-		_, err = c.k8sClient.CoreV1().PersistentVolumes().Update(ctx, pv, metav1.UpdateOptions{})
+
+		newPV := pv.DeepCopy()
+		if newPV.Labels == nil {
+			newPV.Labels = make(map[string]string)
+		}
+		newPV.Labels[key] = value
+
+		newData, err := json.Marshal(newPV)
+		if err != nil {
+			errMsg := fmt.Sprintf("Failed to marshal updated PV %s with labels: %v", pvName, err)
+			log.Error(errMsg)
+			return err
+		}
+
+		patchBytes, err := strategicpatch.CreateTwoWayMergePatch(oldData, newData, pv)
+		if err != nil {
+			errMsg := fmt.Sprintf("Error creating two way merge patch for PV %s with error: %v", pvName, err)
+			log.Error(errMsg)
+			return err
+		}
+
+		_, err = c.k8sClient.CoreV1().PersistentVolumes().Patch(ctx, pv.Name, k8stypes.StrategicMergePatchType,
+			patchBytes, metav1.PatchOptions{})
 		if err != nil {
 			errMsg := fmt.Sprintf("error updating PV %s with labels %s/%s. Error: %v", pvName, key, value, err)
 			log.Error(errMsg)

pkg/kubernetes/kubernetes.go

@@ -19,6 +19,7 @@ package kubernetes
 import (
 	"context"
 	"embed"
+	"encoding/json"
 	"flag"
 	"fmt"
 	"net"
@@ -40,6 +41,8 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/runtime/serializer"
+	k8stypes "k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/util/strategicpatch"
 	"k8s.io/apimachinery/pkg/util/wait"
 	utilyaml "k8s.io/apimachinery/pkg/util/yaml"
 	clientset "k8s.io/client-go/kubernetes"
@@ -728,8 +731,28 @@ func RetainPersistentVolume(ctx context.Context, k8sClient clientset.Interface,
 		return err
 	}
 
-	pv.Spec.PersistentVolumeReclaimPolicy = v1.PersistentVolumeReclaimRetain
-	_, err = k8sClient.CoreV1().PersistentVolumes().Update(ctx, pv, metav1.UpdateOptions{})
+	oldData, err := json.Marshal(pv)
+	if err != nil {
+		log.Errorf("Failed to marshal PV: %v, Error: %v", pv, err)
+		return err
+	}
+
+	newPV := pv.DeepCopy()
+	newPV.Spec.PersistentVolumeReclaimPolicy = v1.PersistentVolumeReclaimRetain
+	newData, err := json.Marshal(newPV)
+	if err != nil {
+		log.Errorf("Failed to marshal updated PV with reclaim policy: %v, Error: %v", newPV, err)
+		return err
+	}
+
+	patchBytes, err := strategicpatch.CreateTwoWayMergePatch(oldData, newData, pv)
+	if err != nil {
+		log.Errorf("Error creating two way merge patch for PV %q with error: %v", pv.Name, err)
+		return err
+	}
+
+	_, err = k8sClient.CoreV1().PersistentVolumes().Patch(ctx, pv.Name, k8stypes.StrategicMergePatchType,
+		patchBytes, metav1.PatchOptions{})
 	if err != nil {
 		log.Errorf("Failed to set the reclaim policy to retain. Error: %s", err.Error())
 		return err