Run kustomize build with kustomize localize and add a no-verify flag.

kustomize/commands/localize/localize.go

@@ -4,10 +4,14 @@
 package localize
 
 import (
+	"bytes"
 	"log"
+	"path/filepath"
 
 	"github.com/spf13/cobra"
 	lclzr "sigs.k8s.io/kustomize/api/krusty/localizer"
+	"sigs.k8s.io/kustomize/kustomize/v5/commands/build"
+	"sigs.k8s.io/kustomize/kyaml/copyutil"
 	"sigs.k8s.io/kustomize/kyaml/errors"
 	"sigs.k8s.io/kustomize/kyaml/filesys"
 )
@@ -20,23 +24,26 @@ type arguments struct {
 }
 
 type flags struct {
-	scope string
+	scope    string
+	noVerify bool
 }
 
 // NewCmdLocalize returns a new localize command.
 func NewCmdLocalize(fs filesys.FileSystem) *cobra.Command {
 	var f flags
+	var buildBuffer bytes.Buffer
+	buildCmd := build.NewCmdBuild(fs, &build.Help{}, &buildBuffer)
 	cmd := &cobra.Command{
 		Use:   "localize [target [destination]]",
 		Short: "[Alpha] Creates localized copy of target kustomization root at destination",
-		Long: `[Alpha] Creates copy of target kustomization directory or 
-versioned URL at destination, where remote references in the original 
+		Long: `[Alpha] Creates copy of target kustomization directory or
+versioned URL at destination, where remote references in the original
 are replaced by local references to the downloaded remote content.
 
-If target is not specified, the current working directory will be used. 
-Destination is a path to a new directory in an existing directory. If 
-destination is not specified, a new directory will be created in the current 
-working directory. 
+If target is not specified, the current working directory will be used.
+Destination is a path to a new directory in an existing directory. If
+destination is not specified, a new directory will be created in the current
+working directory.
 
 For details, see: https://kubectl.docs.kubernetes.io/references/kustomize/cmd/
 
@@ -46,7 +53,7 @@ alphabetizes kustomization fields in the localized copy.
 `,
 		Example: `
 # Localize the current working directory, with default scope and destination
-kustomize localize 
+kustomize localize
 
 # Localize some local directory, with scope and default destination
 kustomize localize /home/path/scope/target --scope /home/path/scope
@@ -62,6 +69,30 @@ kustomize localize https://github.com/kubernetes-sigs/kustomize//api/krusty/test
 			if err != nil {
 				return errors.Wrap(err)
 			}
+
+			if !f.noVerify {
+				originalBuild, err := runBuildCmd(buildBuffer, buildCmd, args.target)
+				if err != nil {
+					return errors.Wrap(err)
+				}
+
+				buildDst := dst
+				if f.scope != "" && f.scope != args.target {
+					buildDst = filepath.Join(dst, filepath.Base(args.target))
+				}
+
+				localizedBuild, err := runBuildCmd(buildBuffer, buildCmd, buildDst)
+				if err != nil {
+					return errors.Wrap(err)
+				}
+
+				if localizedBuild != originalBuild {
+					copyutil.PrettyFileDiff(originalBuild, localizedBuild)
+					log.Fatalf("VERIFICATION FAILED: `kustomize build` for %s and %s are different after localization.\n", args.target, dst)
+				}
+				log.Printf("VERIFICATION SUCCESS: `kustomize build` for %s and %s are the same after localization.\n", args.target, dst)
+			}
+
 			log.Printf("SUCCESS: localized %q to directory %s\n", args.target, dst)
 			return nil
 		},
@@ -74,6 +105,12 @@ kustomize localize https://github.com/kubernetes-sigs/kustomize//api/krusty/test
 Cannot specify for remote targets, as scope is by default the containing repo.
 If not specified for local target, scope defaults to target.
 `)
+	cmd.Flags().BoolVar(&f.noVerify,
+		"no-verify",
+		false,
+		`Does not verify that the outputs of kustomize build for target and newDir are the same after localization.
+		If not specified, this flag defaults to false and will run kustomize build.
+	`)
 	return cmd
 }
 
@@ -92,3 +129,16 @@ func matchArgs(rawArgs []string) arguments {
 	}
 	return args
 }
+
+func runBuildCmd(buffer bytes.Buffer, cmd *cobra.Command, folder string) (buildOutput string, err error) {
+	buffer.Reset()
+	buildErr := cmd.RunE(cmd, []string{folder})
+	if buildErr != nil {
+		log.Printf("If your target directory requires flags to build: \n"+
+			"1. Add executable permissions for the downloaded exec binaries in '%s'. \n"+
+			"2. Run kustomize build with the necessary flags and self-verify the outputs.", folder)
+		return "", errors.Wrap(buildErr)
+	}
+
+	return buffer.String(), nil
+}

kustomize/commands/localize/localize_test.go

@@ -39,6 +39,24 @@ spec:
         - containerPort: 80
 `
 
+const helmKustomization = `apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+helmCharts:
+- name: external-dns
+  repo: oci://registry-1.docker.io/bitnamicharts
+  version: 6.19.2
+  releaseName: test
+  valuesInline:
+    crd:
+      create: false
+    rbac:
+      create: false
+    serviceAccount:
+      create: false
+    service:
+      enabled: false
+`
+
 func TestScopeFlag(t *testing.T) {
 	kustomizations := map[string]string{
 		filepath.Join("target", "kustomization.yaml"): fmt.Sprintf(`resources:
@@ -66,6 +84,60 @@ func TestScopeFlag(t *testing.T) {
 	loctest.CheckFs(t, testDir.String(), expected, actual)
 }
 
+func TestNoVerifyFlag(t *testing.T) {
+	kustomization := map[string]string{
+		"kustomization.yaml": `resources:
+- deployment.yaml
+`,
+		"deployment.yaml": deployment,
+	}
+	expected, actual, target := loctest.PrepareFs(t, nil, kustomization)
+
+	buffy := new(bytes.Buffer)
+	log.SetOutput(buffy)
+	defer func() {
+		log.SetOutput(os.Stderr)
+	}()
+	cmd := localize.NewCmdLocalize(actual)
+	require.NoError(t, cmd.Flags().Set("no-verify", "true"))
+	err := cmd.RunE(cmd, []string{
+		target.String(),
+		target.Join("dst"),
+	})
+	require.NoError(t, err)
+
+	loctest.SetupDir(t, expected, target.Join("dst"), kustomization)
+	loctest.CheckFs(t, target.String(), expected, actual)
+
+	successMsg := fmt.Sprintf(`SUCCESS: localized "%s" to directory %s
+`, target.String(), target.Join("dst"))
+	verifyMsg := "VERIFICATION"
+	require.NotContains(t, buffy.String(), verifyMsg)
+	require.Contains(t, buffy.String(), successMsg)
+}
+
+func TestFailingBuildCmd(t *testing.T) {
+	kustomization := map[string]string{
+		"kustomization.yaml": helmKustomization,
+	}
+	_, actual, target := loctest.PrepareFs(t, nil, kustomization)
+
+	buffy := new(bytes.Buffer)
+	log.SetOutput(buffy)
+	defer func() {
+		log.SetOutput(os.Stderr)
+	}()
+	cmd := localize.NewCmdLocalize(actual)
+	err := cmd.RunE(cmd, []string{
+		target.String(),
+		target.Join("dst"),
+	})
+	require.Error(t, err)
+
+	verifyMsg := "If your target directory requires flags to build"
+	require.Contains(t, buffy.String(), verifyMsg)
+}
+
 func TestOptionalArgs(t *testing.T) {
 	for name, args := range map[string][]string{
 		"no_target": {},
@@ -99,6 +171,8 @@ func TestOptionalArgs(t *testing.T) {
 			loctest.SetupDir(t, expected, dst, kust)
 			loctest.CheckFs(t, testDir.String(), expected, actual)
 
+			verifyMsg := "VERIFICATION SUCCESS"
+			require.Contains(t, buffy.String(), verifyMsg)
 			successMsg := fmt.Sprintf(`SUCCESS: localized "." to directory %s
 `, dst)
 			require.Contains(t, buffy.String(), successMsg)
@@ -128,6 +202,8 @@ func TestOutput(t *testing.T) {
 	loctest.SetupDir(t, expected, target.Join("dst"), kustomization)
 	loctest.CheckFs(t, target.String(), expected, actual)
 
+	verifyMsg := "VERIFICATION SUCCESS"
+	require.Contains(t, buffy.String(), verifyMsg)
 	successMsg := fmt.Sprintf(`SUCCESS: localized "%s" to directory %s
 `, target.String(), target.Join("dst"))
 	require.Contains(t, buffy.String(), successMsg)