Use mergepatch for PDB (#584)

Signed-off-by: Tamal Saha <[email protected]>

policy/v1/pdb.go

@@ -19,12 +19,12 @@ package v1
 import (
 	"context"
 
+	jsonpatch "github.com/evanphx/json-patch"
 	"github.com/pkg/errors"
 	policy "k8s.io/api/policy/v1"
 	kerr "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
-	"k8s.io/apimachinery/pkg/util/strategicpatch"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/klog/v2"
@@ -67,15 +67,15 @@ func PatchPodDisruptionBudgetObject(ctx context.Context, c kubernetes.Interface,
 		return nil, kutil.VerbUnchanged, err
 	}
 
-	patch, err := strategicpatch.CreateTwoWayMergePatch(curJson, modJson, policy.PodDisruptionBudget{})
+	patch, err := jsonpatch.CreateMergePatch(curJson, modJson)
 	if err != nil {
 		return nil, kutil.VerbUnchanged, err
 	}
 	if len(patch) == 0 || string(patch) == "{}" {
 		return cur, kutil.VerbUnchanged, nil
 	}
 	klog.V(3).Infof("Patching PodDisruptionBudget %s with %s.", cur.Name, string(patch))
-	out, err := c.PolicyV1().PodDisruptionBudgets(cur.Namespace).Patch(ctx, cur.Name, types.StrategicMergePatchType, patch, opts)
+	out, err := c.PolicyV1().PodDisruptionBudgets(cur.Namespace).Patch(ctx, cur.Name, types.MergePatchType, patch, opts)
 	return out, kutil.VerbPatched, err
 }