add kustomizationVisitor type and use it when kustomization is enabled

staging/src/k8s.io/cli-runtime/pkg/genericclioptions/resource/BUILD

@@ -35,12 +35,16 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/yaml:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/watch:go_default_library",
+        "//staging/src/k8s.io/cli-runtime/pkg/kustomize/k8sdeps:go_default_library",
         "//staging/src/k8s.io/client-go/discovery:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes/scheme:go_default_library",
         "//staging/src/k8s.io/client-go/rest:go_default_library",
         "//staging/src/k8s.io/client-go/restmapper:go_default_library",
         "//vendor/golang.org/x/text/encoding/unicode:go_default_library",
         "//vendor/golang.org/x/text/transform:go_default_library",
+        "//vendor/sigs.k8s.io/kustomize/pkg/commands/build:go_default_library",
+        "//vendor/sigs.k8s.io/kustomize/pkg/constants:go_default_library",
+        "//vendor/sigs.k8s.io/kustomize/pkg/fs:go_default_library",
     ],
 )
 

staging/src/k8s.io/cli-runtime/pkg/genericclioptions/resource/builder.go

@@ -130,8 +130,9 @@ func IsUsageError(err error) bool {
 }
 
 type FilenameOptions struct {
-	Filenames []string
+	Filenames           []string
-	Recursive bool
+	Recursive           bool
+	EnableKustomization bool
 }
 
 type resourceTuple struct {
@@ -197,6 +198,7 @@ func (b *Builder) AddError(err error) *Builder {
 // recognized will be ignored (but logged at V(2)).
 func (b *Builder) FilenameParam(enforceNamespace bool, filenameOptions *FilenameOptions) *Builder {
 	recursive := filenameOptions.Recursive
+	enableKustomization := filenameOptions.EnableKustomization
 	paths := filenameOptions.Filenames
 	for _, s := range paths {
 		switch {
@@ -213,7 +215,7 @@ func (b *Builder) FilenameParam(enforceNamespace bool, filenameOptions *Filename
 			if !recursive {
 				b.singleItemImplied = true
 			}
-			b.Path(recursive, s)
+			b.Path(recursive, enableKustomization, s)
 		}
 	}
 
@@ -332,7 +334,7 @@ func (b *Builder) Stream(r io.Reader, name string) *Builder {
 // FileVisitor is streaming the content to a StreamVisitor. If ContinueOnError() is set
 // prior to this method being called, objects on the path that are unrecognized will be
 // ignored (but logged at V(2)).
-func (b *Builder) Path(recursive bool, paths ...string) *Builder {
+func (b *Builder) Path(recursive, enableKustomization bool, paths ...string) *Builder {
 	for _, p := range paths {
 		_, err := os.Stat(p)
 		if os.IsNotExist(err) {
@@ -344,7 +346,7 @@ func (b *Builder) Path(recursive bool, paths ...string) *Builder {
 			continue
 		}
 
-		visitors, err := ExpandPathsToFileVisitors(b.mapper, p, recursive, FileExtensions, b.schema)
+		visitors, err := ExpandPathsToFileVisitors(b.mapper, p, recursive, enableKustomization, FileExtensions, b.schema)
 		if err != nil {
 			b.errs = append(b.errs, fmt.Errorf("error reading %q: %v", p, err))
 		}

staging/src/k8s.io/cli-runtime/pkg/genericclioptions/resource/visitor.go

@@ -20,6 +20,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"net/http"
 	"net/url"
 	"os"
@@ -38,6 +39,10 @@ import (
 	utilerrors "k8s.io/apimachinery/pkg/util/errors"
 	"k8s.io/apimachinery/pkg/util/yaml"
 	"k8s.io/apimachinery/pkg/watch"
+	"k8s.io/cli-runtime/pkg/kustomize/k8sdeps"
+	"sigs.k8s.io/kustomize/pkg/commands/build"
+	"sigs.k8s.io/kustomize/pkg/constants"
+	"sigs.k8s.io/kustomize/pkg/fs"
 )
 
 const (
@@ -446,13 +451,16 @@ func FileVisitorForSTDIN(mapper *mapper, schema ContentValidator) Visitor {
 // ExpandPathsToFileVisitors will return a slice of FileVisitors that will handle files from the provided path.
 // After FileVisitors open the files, they will pass an io.Reader to a StreamVisitor to do the reading. (stdin
 // is also taken care of). Paths argument also accepts a single file, and will return a single visitor
-func ExpandPathsToFileVisitors(mapper *mapper, paths string, recursive bool, extensions []string, schema ContentValidator) ([]Visitor, error) {
+func ExpandPathsToFileVisitors(mapper *mapper, paths string, recursive bool, enableKustomize bool, extensions []string, schema ContentValidator) ([]Visitor, error) {
 	var visitors []Visitor
 	err := filepath.Walk(paths, func(path string, fi os.FileInfo, err error) error {
 		if err != nil {
 			return err
 		}
-
+		if enableKustomize && isKustomizationDir(path) {
+			visitors = append(visitors, NewKustomizationVisitor(mapper, path, schema))
+			return filepath.SkipDir
+		}
 		if fi.IsDir() {
 			if path != paths && !recursive {
 				return filepath.SkipDir
@@ -463,7 +471,10 @@ func ExpandPathsToFileVisitors(mapper *mapper, paths string, recursive bool, ext
 		if path != paths && ignoreFile(path, extensions) {
 			return nil
 		}
-
+		if enableKustomize && filepath.Base(path) == constants.KustomizationFileName {
+			visitors = append(visitors, NewKustomizationVisitor(mapper, filepath.Dir(path), schema))
+			return nil
+		}
 		visitor := &FileVisitor{
 			Path:          path,
 			StreamVisitor: NewStreamVisitor(nil, mapper, path, schema),
@@ -479,6 +490,13 @@ func ExpandPathsToFileVisitors(mapper *mapper, paths string, recursive bool, ext
 	return visitors, nil
 }
 
+func isKustomizationDir(path string) bool {
+	if _, err := os.Stat(filepath.Join(path, constants.KustomizationFileName)); err == nil {
+		return true
+	}
+	return false
+}
+
 // FileVisitor is wrapping around a StreamVisitor, to handle open/close files
 type FileVisitor struct {
 	Path string
@@ -507,6 +525,37 @@ func (v *FileVisitor) Visit(fn VisitorFunc) error {
 	return v.StreamVisitor.Visit(fn)
 }
 
+// KustomizationVisitor prorvides the output of kustomization build
+type KustomizationVisitor struct {
+	Path string
+	*StreamVisitor
+}
+
+// Visit in a KustomizationVisitor build the kustomization output
+func (v *KustomizationVisitor) Visit(fn VisitorFunc) error {
+	fSys := fs.MakeRealFS()
+	f := k8sdeps.NewFactory()
+	var out bytes.Buffer
+	cmd := build.NewCmdBuild(&out, fSys, f.ResmapF, f.TransformerF)
+	cmd.SetArgs([]string{v.Path})
+	// we want to silence usage, error output, and any future output from cobra
+	// we will get error output as a golang error from execute
+	cmd.SetOutput(ioutil.Discard)
+	_, err := cmd.ExecuteC()
+	if err != nil {
+		return err
+	}
+	v.StreamVisitor.Reader = bytes.NewReader(out.Bytes())
+	return v.StreamVisitor.Visit(fn)
+}
+
+func NewKustomizationVisitor(mapper *mapper, path string, schema ContentValidator) *KustomizationVisitor {
+	return &KustomizationVisitor{
+		Path:          path,
+		StreamVisitor: NewStreamVisitor(nil, mapper, path, schema),
+	}
+}
+
 // StreamVisitor reads objects from an io.Reader and walks them. A stream visitor can only be
 // visited once.
 // TODO: depends on objects being in JSON format before being passed to decode - need to implement