feat: support replace strategy for CRD (argoproj#252)

Signed-off-by: Alexander Matyushentsev <[email protected]>

Author: Alexander Matyushentsev

pkg/sync/sync_context.go

@@ -819,10 +819,21 @@ func (sc *syncContext) applyObject(t *syncTask, dryRun bool, force bool, validat
 	var err error
 	var message string
 	shouldReplace := sc.replace || resourceutil.HasAnnotationOption(t.targetObj, common.AnnotationSyncOptions, common.SyncOptionReplace)
-	// always use 'kubectl apply' for CRDs since 'replace' might recreate resource and so delete all CRD instances
-	if shouldReplace && !kube.IsCRD(t.targetObj) {
+	if shouldReplace {
 		if t.liveObj != nil {
-			message, err = sc.kubectl.ReplaceResource(context.TODO(), sc.rawConfig, t.targetObj, t.targetObj.GetNamespace(), dryRunStrategy, force)
+			// Avoid using `kubectl replace` for CRDs since 'replace' might recreate resource and so delete all CRD instances
+			if kube.IsCRD(t.targetObj) {
+				update := t.targetObj.DeepCopy()
+				update.SetResourceVersion(t.liveObj.GetResourceVersion())
+				_, err = sc.kubectl.UpdateResource(context.TODO(), sc.rawConfig, update, t.targetObj.GetNamespace(), dryRunStrategy)
+				if err == nil {
+					message = fmt.Sprintf("%s/%s updated", t.targetObj.GetKind(), t.targetObj.GetName())
+				} else {
+					message = fmt.Sprintf("error when updating: %v", err.Error())
+				}
+			} else {
+				message, err = sc.kubectl.ReplaceResource(context.TODO(), sc.rawConfig, t.targetObj, t.targetObj.GetNamespace(), dryRunStrategy, force)
+			}
 		} else {
 			_, err = sc.kubectl.CreateResource(context.TODO(), sc.rawConfig, t.targetObj, t.targetObj.GetNamespace(), dryRunStrategy)
 			if err == nil {

pkg/utils/kube/ctl.go

@@ -42,6 +42,7 @@ type Kubectl interface {
 	ApplyResource(ctx context.Context, config *rest.Config, obj *unstructured.Unstructured, namespace string, dryRunStrategy cmdutil.DryRunStrategy, force, validate bool) (string, error)
 	ReplaceResource(ctx context.Context, config *rest.Config, obj *unstructured.Unstructured, namespace string, dryRunStrategy cmdutil.DryRunStrategy, force bool) (string, error)
 	CreateResource(ctx context.Context, config *rest.Config, obj *unstructured.Unstructured, namespace string, dryRunStrategy cmdutil.DryRunStrategy) (*unstructured.Unstructured, error)
+	UpdateResource(ctx context.Context, config *rest.Config, obj *unstructured.Unstructured, namespace string, dryRunStrategy cmdutil.DryRunStrategy) (*unstructured.Unstructured, error)
 	ConvertToVersion(obj *unstructured.Unstructured, group, version string) (*unstructured.Unstructured, error)
 	DeleteResource(ctx context.Context, config *rest.Config, gvk schema.GroupVersionKind, name string, namespace string, deleteOptions metav1.DeleteOptions) error
 	GetResource(ctx context.Context, config *rest.Config, gvk schema.GroupVersionKind, name string, namespace string) (*unstructured.Unstructured, error)
@@ -368,6 +369,35 @@ func (k *KubectlCmd) CreateResource(ctx context.Context, config *rest.Config, ob
 	return resourceIf.Create(ctx, obj, createOptions)
 }
 
+func (k *KubectlCmd) UpdateResource(ctx context.Context, config *rest.Config, obj *unstructured.Unstructured, namespace string, dryRunStrategy cmdutil.DryRunStrategy) (*unstructured.Unstructured, error) {
+	gvk := obj.GroupVersionKind()
+	span := k.Tracer.StartSpan("UpdateResource")
+	span.SetBaggageItem("kind", gvk.Kind)
+	span.SetBaggageItem("name", obj.GetName())
+	defer span.Finish()
+	dynamicIf, err := dynamic.NewForConfig(config)
+	if err != nil {
+		return nil, err
+	}
+	disco, err := discovery.NewDiscoveryClientForConfig(config)
+	if err != nil {
+		return nil, err
+	}
+	apiResource, err := ServerResourceForGroupVersionKind(disco, gvk)
+	if err != nil {
+		return nil, err
+	}
+	resource := gvk.GroupVersion().WithResource(apiResource.Name)
+	resourceIf := ToResourceInterface(dynamicIf, apiResource, resource, namespace)
+
+	updateOptions := metav1.UpdateOptions{}
+	switch dryRunStrategy {
+	case cmdutil.DryRunClient, cmdutil.DryRunServer:
+		updateOptions.DryRun = []string{metav1.DryRunAll}
+	}
+	return resourceIf.Update(ctx, obj, updateOptions)
+}
+
 // ApplyResource performs an apply of a unstructured resource
 func (k *KubectlCmd) ApplyResource(ctx context.Context, config *rest.Config, obj *unstructured.Unstructured, namespace string, dryRunStrategy cmdutil.DryRunStrategy, force, validate bool) (string, error) {
 	span := k.Tracer.StartSpan("ApplyResource")

pkg/utils/kube/kubetest/mock.go

@@ -98,6 +98,15 @@ func (k *MockKubectlCmd) CreateResource(ctx context.Context, config *rest.Config
 	return obj, command.Err
 }
 
+func (k *MockKubectlCmd) UpdateResource(ctx context.Context, config *rest.Config, obj *unstructured.Unstructured, namespace string, dryRunStrategy cmdutil.DryRunStrategy) (*unstructured.Unstructured, error) {
+	k.SetLastResourceCommand(kube.GetResourceKey(obj), "update")
+	command, ok := k.Commands[obj.GetName()]
+	if !ok {
+		return obj, nil
+	}
+	return obj, command.Err
+}
+
 func (k *MockKubectlCmd) ApplyResource(ctx context.Context, config *rest.Config, obj *unstructured.Unstructured, namespace string, dryRunStrategy cmdutil.DryRunStrategy, force, validate bool) (string, error) {
 	k.SetLastValidate(validate)
 	k.SetLastResourceCommand(kube.GetResourceKey(obj), "apply")