retain necessary fields in Pod object

Signed-off-by: changzhen <changzhen5@huawei.com>

pkg/util/helper/unstructured.go

@@ -1,6 +1,9 @@
 package helper
 
 import (
+	appsv1 "k8s.io/api/apps/v1"
+	batchv1 "k8s.io/api/batch/v1"
+	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
 
@@ -37,3 +40,63 @@ func ConvertToResourceBinding(obj *unstructured.Unstructured) (*workv1alpha1.Res
 
 	return typedObj, nil
 }
+
+// ConvertToPod converts a Pod object from unstructured to typed.
+func ConvertToPod(obj *unstructured.Unstructured) (*corev1.Pod, error) {
+	typedObj := &corev1.Pod{}
+	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(obj.UnstructuredContent(), typedObj); err != nil {
+		return nil, err
+	}
+
+	return typedObj, nil
+}
+
+// ConvertToReplicaSet converts a ReplicaSet object from unstructured to typed.
+func ConvertToReplicaSet(obj *unstructured.Unstructured) (*appsv1.ReplicaSet, error) {
+	typedObj := &appsv1.ReplicaSet{}
+	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(obj.UnstructuredContent(), typedObj); err != nil {
+		return nil, err
+	}
+
+	return typedObj, nil
+}
+
+// ConvertToDeployment converts a Deployment object from unstructured to typed.
+func ConvertToDeployment(obj *unstructured.Unstructured) (*appsv1.Deployment, error) {
+	typedObj := &appsv1.Deployment{}
+	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(obj.UnstructuredContent(), typedObj); err != nil {
+		return nil, err
+	}
+
+	return typedObj, nil
+}
+
+// ConvertToDaemonSet converts a DaemonSet object from unstructured to typed.
+func ConvertToDaemonSet(obj *unstructured.Unstructured) (*appsv1.DaemonSet, error) {
+	typedObj := &appsv1.DaemonSet{}
+	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(obj.UnstructuredContent(), typedObj); err != nil {
+		return nil, err
+	}
+
+	return typedObj, nil
+}
+
+// ConvertToStatefulSet converts a StatefulSet object from unstructured to typed.
+func ConvertToStatefulSet(obj *unstructured.Unstructured) (*appsv1.StatefulSet, error) {
+	typedObj := &appsv1.StatefulSet{}
+	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(obj.UnstructuredContent(), typedObj); err != nil {
+		return nil, err
+	}
+
+	return typedObj, nil
+}
+
+// ConvertToJob converts a Job object from unstructured to typed.
+func ConvertToJob(obj *unstructured.Unstructured) (*batchv1.Job, error) {
+	typedObj := &batchv1.Job{}
+	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(obj.UnstructuredContent(), typedObj); err != nil {
+		return nil, err
+	}
+
+	return typedObj, nil
+}

pkg/util/objectwatcher/retain.go

@@ -4,8 +4,10 @@ import (
 	"fmt"
 
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime"
 
 	"github.com/karmada-io/karmada/pkg/util"
+	"github.com/karmada-io/karmada/pkg/util/helper"
 )
 
 /*
@@ -50,16 +52,35 @@ func RetainClusterFields(desiredObj, clusterObj *unstructured.Unstructured) erro
 }
 
 func retainPodFields(desiredObj, clusterObj *unstructured.Unstructured) error {
-	nodeName, ok, err := unstructured.NestedString(clusterObj.Object, "spec", "nodeName")
+	desiredPod, err := helper.ConvertToPod(desiredObj)
 	if err != nil {
-		return fmt.Errorf("error retrieving nodeName from cluster pod: %w", err)
+		return fmt.Errorf("failed to convert desiredPod from unstructured object: %v", err)
 	}
-	if ok && nodeName != "" {
+
-		err := unstructured.SetNestedField(desiredObj.Object, nodeName, "spec", "nodeName")
+	clusterPod, err := helper.ConvertToPod(clusterObj)
-		if err != nil {
+	if err != nil {
-			return fmt.Errorf("error setting nodeName for pod: %w", err)
+		return fmt.Errorf("failed to convert clusterPod from unstructured object: %v", err)
+	}
+
+	desiredPod.Spec.NodeName = clusterPod.Spec.NodeName
+	desiredPod.Spec.ServiceAccountName = clusterPod.Spec.ServiceAccountName
+	desiredPod.Spec.Volumes = clusterPod.Spec.Volumes
+	// retain volumeMounts in each container
+	for _, clusterContainer := range clusterPod.Spec.Containers {
+		for desiredIndex, desiredContainer := range desiredPod.Spec.Containers {
+			if desiredContainer.Name == clusterContainer.Name {
+				desiredPod.Spec.Containers[desiredIndex].VolumeMounts = clusterContainer.VolumeMounts
+				break
+			}
 		}
 	}
+
+	unCastObj, err := runtime.DefaultUnstructuredConverter.ToUnstructured(desiredPod)
+	if err != nil {
+		return fmt.Errorf("failed to transform Pod: %v", err)
+	}
+
+	desiredObj.Object = unCastObj
 	return nil
 }