Add --reorder flag.

plugin/builtin/legacyordertransformer/LegacyOrderTransformer.go

@@ -0,0 +1,41 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+//go:generate go run sigs.k8s.io/kustomize/plugin/pluginator
+package main
+
+import (
+	"sigs.k8s.io/kustomize/pkg/ifc"
+	"sigs.k8s.io/kustomize/pkg/resmap"
+	"sigs.k8s.io/kustomize/pkg/resource"
+	"sort"
+)
+
+// Sort the resources using an ordering defined in the Gvk class.
+// This puts cluster-wide basic resources with no
+// dependencies (like Namespace, StorageClass, etc.)
+// first, and resources with a high number of dependencies
+// (like ValidatingWebhookConfiguration) last.
+type plugin struct{}
+
+var KustomizePlugin plugin
+
+// Nothing needed for configuration.
+func (p *plugin) Config(
+	ldr ifc.Loader, rf *resmap.Factory, c []byte) (err error) {
+	return nil
+}
+
+func (p *plugin) Transform(m resmap.ResMap) error {
+	resources := make([]*resource.Resource, m.Size())
+	ids := m.AllIds()
+	sort.Sort(resmap.IdSlice(ids))
+	for i, id := range ids {
+		resources[i] = m.GetById(id)
+	}
+	m.Clear()
+	for i, id := range ids {
+		m.AppendWithId(id, resources[i])
+	}
+	return nil
+}