Backup metadata fields before compare

Generated object won't have them, thus the compare will always be false
but that doesn't mean that semantically they are different.

pkg/apply/apply.go

@@ -2,16 +2,17 @@ package apply
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"log"
 
 	"github.com/pkg/errors"
 
 	"k8s.io/apimachinery/pkg/api/equality"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	uns "k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/types"
+	// diff "k8s.io/apimachinery/pkg/util/diff"
 	k8sclient "sigs.k8s.io/controller-runtime/pkg/client"
 )
 
@@ -50,15 +51,24 @@ func ApplyObject(ctx context.Context, client k8sclient.Client, obj *uns.Unstruct
 		return errors.Wrapf(err, "could not retrieve existing %s", objDesc)
 	}
 
-	// Merge the desired object with what actually exists
-	if err := MergeObjectForUpdate(existing, obj); err != nil {
-		return errors.Wrapf(err, "could not merge object %s with existing", objDesc)
-	}
-	if !equality.Semantic.DeepEqual(existing, obj) {
-		marshaled_existing, _ := json.MarshalIndent(existing, "", "    ")
-		log.Printf(string(marshaled_existing))
-		marshaled_merged, _ := json.MarshalIndent(obj, "", "    ")
-		log.Printf(string(marshaled_merged))
+	creationTimeStamp := existing.GetCreationTimestamp()
+	existing.SetCreationTimestamp(metav1.Time{})
+	selfLink := existing.GetSelfLink()
+	existing.SetSelfLink("")
+	uid := existing.GetUID()
+	existing.SetUID(types.UID(""))
+	resourceVersion := existing.GetResourceVersion()
+	existing.SetResourceVersion("")
+
+	if !equality.Semantic.DeepDerivative(existing, obj) {
+		// Merge the desired object with what actually exists
+		existing.SetCreationTimestamp(creationTimeStamp)
+		existing.SetSelfLink(selfLink)
+		existing.SetUID(uid)
+		existing.SetResourceVersion(resourceVersion)
+		if err := MergeObjectForUpdate(existing, obj); err != nil {
+			return errors.Wrapf(err, "could not merge object %s with existing", objDesc)
+		}
 		if err := client.Update(ctx, obj); err != nil {
 			return errors.Wrapf(err, "could not update object %s", objDesc)
 		} else {