🌱 Improve patch helper for no-op cases

util/patch/patch.go

@@ -19,6 +19,7 @@ package patch
 import (
 	"context"
 	"encoding/json"
+	"reflect"
 	"time"
 
 	"github.com/pkg/errors"
@@ -70,26 +71,9 @@ func NewHelper(obj client.Object, crClient client.Client) (*Helper, error) {
 		return nil, errors.New("failed to create patch helper: object is nil")
 	}
 
-	// Get the GroupVersionKind of the object,
-	// used to validate against later on.
-	gvk, err := apiutil.GVKForObject(obj, crClient.Scheme())
-	if err != nil {
-		return nil, errors.Wrapf(err, "failed to create patch helper for object %s", klog.KObj(obj))
-	}
-
-	// Identify location of the condition fields according to the canonical place defined by the proposal for
-	// improving status in Cluster API conditions.
-	metav1ConditionsFieldPath, clusterv1ConditionsFieldPath, err := identifyConditionsFieldsPath(obj)
-	if err != nil {
-		return nil, errors.Wrapf(err, "failed to identify condition fields for object %s", klog.KObj(obj))
-	}
-
 	return &Helper{
-		client:                       crClient,
-		gvk:                          gvk,
-		beforeObject:                 obj.DeepCopyObject().(client.Object),
-		metav1ConditionsFieldPath:    metav1ConditionsFieldPath,
-		clusterv1ConditionsFieldPath: clusterv1ConditionsFieldPath,
+		client:       crClient,
+		beforeObject: obj.DeepCopyObject().(client.Object),
 	}, nil
 }
 
@@ -100,13 +84,31 @@ func (h *Helper) Patch(ctx context.Context, obj client.Object, opts ...Option) e
 		return errors.Errorf("failed to patch %s %s: modified object is nil", h.gvk.Kind, klog.KObj(h.beforeObject))
 	}
 
+	if reflect.DeepEqual(obj, h.beforeObject) {
+		return nil
+	}
+
+	// Get the GroupVersionKind of the object,
+	// used to validate against later on.
+	beforeGvk, err := apiutil.GVKForObject(h.beforeObject, h.client.Scheme())
+	if err != nil {
+		return errors.Wrapf(err, "failed to create patch helper for object %s", klog.KObj(obj))
+	}
+
 	// Get the GroupVersionKind of the object that we want to patch.
-	gvk, err := apiutil.GVKForObject(obj, h.client.Scheme())
+	h.gvk, err = apiutil.GVKForObject(obj, h.client.Scheme())
 	if err != nil {
 		return errors.Wrapf(err, "failed to patch %s %s", h.gvk.Kind, klog.KObj(h.beforeObject))
 	}
-	if gvk != h.gvk {
-		return errors.Errorf("failed to patch %s %s: unmatched GroupVersionKind, expected %q got %q", h.gvk.Kind, klog.KObj(h.beforeObject), h.gvk, gvk)
+	if h.gvk != beforeGvk {
+		return errors.Errorf("failed to patch %s %s: unmatched GroupVersionKind, expected %q got %q", h.gvk.Kind, klog.KObj(h.beforeObject), h.gvk, beforeGvk)
+	}
+
+	// Identify location of the condition fields according to the canonical place defined by the proposal for
+	// improving status in Cluster API conditions.
+	h.metav1ConditionsFieldPath, h.clusterv1ConditionsFieldPath, err = identifyConditionsFieldsPath(obj)
+	if err != nil {
+		return errors.Wrapf(err, "failed to identify condition fields for object %s", klog.KObj(obj))
 	}
 
 	// Calculate the options.
@@ -132,15 +134,15 @@ func (h *Helper) Patch(ctx context.Context, obj client.Object, opts ...Option) e
 	}
 
 	// Convert the before object to unstructured.
-	h.before, err = toUnstructured(h.beforeObject, gvk)
+	h.before, err = toUnstructured(h.beforeObject, h.gvk)
 	if err != nil {
 		return errors.Wrapf(err, "failed to patch %s %s: failed to convert before object to Unstructured", h.gvk.Kind, klog.KObj(h.beforeObject))
 	}
 
 	// Convert the after object to unstructured.
-	h.after, err = toUnstructured(obj, gvk)
+	h.after, err = toUnstructured(obj, h.gvk)
 	if err != nil {
-		return errors.Wrapf(err, "failed to patch %s %s: failed to convert after object to Unstructured", h.gvk.Kind, klog.KObj(h.beforeObject))
+		return errors.Wrapf(err, "failed to patch %s %s: failed to convert after object to Unstructured", h.gvk.Kind, klog.KObj(obj))
 	}
 
 	// Include .status.observedGeneration if IncludeStatusObservedGeneration is set.