support different filenames for kustomization file

pkg/commands/build/build.go

@@ -67,7 +67,7 @@ func NewCmdBuild(
 
 	cmd := &cobra.Command{
 		Use:          "build [path]",
-		Short:        "Print current configuration per contents of " + constants.KustomizationFileName,
+		Short:        "Print current configuration per contents of " + constants.KustomizationFileNames[0],
 		Example:      examples,
 		SilenceUsage: true,
 		RunE: func(cmd *cobra.Command, args []string) error {
@@ -88,7 +88,7 @@ func NewCmdBuild(
 // Validate validates build command.
 func (o *BuildOptions) Validate(args []string) error {
 	if len(args) > 1 {
-		return errors.New("specify one path to " + constants.KustomizationFileName)
+		return errors.New("specify one path to " + constants.KustomizationFileNames[0])
 	}
 	if len(args) == 0 {
 		o.kustomizationPath = "./"

pkg/commands/build/build_test.go

@@ -33,7 +33,7 @@ func TestBuildValidate(t *testing.T) {
 		{"file", []string{"beans"}, "beans", ""},
 		{"path", []string{"a/b/c"}, "a/b/c", ""},
 		{"path", []string{"too", "many"},
-			"", "specify one path to " + constants.KustomizationFileName},
+			"", "specify one path to " + constants.KustomizationFileNames[0]},
 	}
 	for _, mycase := range cases {
 		opts := BuildOptions{}

pkg/commands/edit/add/addmetadata.go

@@ -59,7 +59,7 @@ func newCmdAddAnnotation(fSys fs.FileSystem, v func(map[string]string) error) *c
 	o.mapValidator = v
 	cmd := &cobra.Command{
 		Use:   "annotation",
-		Short: "Adds one or more commonAnnotations to " + constants.KustomizationFileName,
+		Short: "Adds one or more commonAnnotations to " + constants.KustomizationFileNames[0],
 		Example: `
 		add annotation {annotationKey1:annotationValue1},{annotationKey2:annotationValue2}`,
 		RunE: func(cmd *cobra.Command, args []string) error {
@@ -76,7 +76,7 @@ func newCmdAddLabel(fSys fs.FileSystem, v func(map[string]string) error) *cobra.
 	o.mapValidator = v
 	cmd := &cobra.Command{
 		Use:   "label",
-		Short: "Adds one or more commonLabels to " + constants.KustomizationFileName,
+		Short: "Adds one or more commonLabels to " + constants.KustomizationFileNames[0],
 		Example: `
 		add label {labelKey1:labelValue1},{labelKey2:labelValue2}`,
 		RunE: func(cmd *cobra.Command, args []string) error {

pkg/commands/kustfile/kustomizationfile.go

@@ -129,12 +129,22 @@ func NewKustomizationFile(fSys fs.FileSystem) (*kustomizationFile, error) { // n
 }
 
 func (mf *kustomizationFile) validate() error {
-	if mf.fSys.Exists(constants.KustomizationFileName) {
-		mf.path = constants.KustomizationFileName
-	} else if mf.fSys.Exists(constants.SecondaryKustomizationFileName) {
-		mf.path = constants.SecondaryKustomizationFileName
-	} else {
-		return fmt.Errorf("Missing kustomization file '%s'.\n", constants.KustomizationFileName)
+	match := 0
+	var path []string
+	for _, kfilename := range constants.KustomizationFileNames {
+		if mf.fSys.Exists(kfilename) {
+			match += 1
+			path = append(path, kfilename)
+		}
+	}
+
+	switch match {
+	case 0:
+		return fmt.Errorf("Missing kustomization file '%s'.\n", constants.KustomizationFileNames[0])
+	case 1:
+		mf.path = path[0]
+	default:
+		return fmt.Errorf("Found multiple kustomization file: %v\n", path)
 	}
 
 	if mf.fSys.IsDir(mf.path) {

pkg/commands/kustfile/kustomizationfile_test.go

@@ -159,12 +159,12 @@ configMapGenerator:
   name: my-configmap
 `
 	fakeFS := fs.MakeFakeFS()
-	fakeFS.WriteFile(constants.SecondaryKustomizationFileName, []byte(kcontent))
+	fakeFS.WriteFile(constants.KustomizationFileNames[1], []byte(kcontent))
 	k, err := NewKustomizationFile(fakeFS)
 	if err != nil {
 		t.Fatalf("Unexpected Error: %v", err)
 	}
-	if k.path != constants.SecondaryKustomizationFileName {
+	if k.path != constants.KustomizationFileNames[1] {
 		t.Fatalf("Load incorrect file path %s", k.path)
 	}
 }

pkg/constants/constants.go

@@ -17,15 +17,12 @@ limitations under the License.
 // Package constants holds global constants for the kustomize tool.
 package constants
 
-// KustomizationFileSuffix is expected suffix for KustomizationFileName.
-const KustomizationFileSuffix = ".yaml"
-
-// SecondaryKustomizationFileSuffix is the second expected suffix when KustomizationFileSuffix is not found
-const SecondaryKustomizationFileSuffix = ".yml"
-
-// KustomizationFileName is the Well-Known File Name for a kustomize configuration file.
-const KustomizationFileName = "kustomization" + KustomizationFileSuffix
-
-// SecondaryKustomizationFileName is the secondary File Name for a kustomize configuration file when
-// KustomizationFileName is not found
-const SecondaryKustomizationFileName = "kustomization" + SecondaryKustomizationFileSuffix
+// KustomizationFileNames is a list of filenames that can be recognized and consumbed
+// by Kustomize.
+// In each directory, Kustomize searches for file with the name in this list.
+// Only one match is allowed.
+var KustomizationFileNames = [3]string{
+	"kustomization.yaml",
+	"kustomization.yml",
+	"Kustomization",
+}

pkg/fs/fakefs.go

@@ -151,7 +151,7 @@ func (fs *fakeFs) ReadFile(name string) ([]byte, error) {
 }
 
 func (fs *fakeFs) ReadTestKustomization() ([]byte, error) {
-	return fs.ReadFile(constants.KustomizationFileName)
+	return fs.ReadFile(constants.KustomizationFileNames[0])
 }
 
 // WriteFile always succeeds and does nothing.
@@ -169,7 +169,7 @@ func (fs *fakeFs) WriteTestKustomization() {
 
 // WriteTestKustomizationWith writes a standard test file.
 func (fs *fakeFs) WriteTestKustomizationWith(bytes []byte) {
-	fs.WriteFile(constants.KustomizationFileName, bytes)
+	fs.WriteFile(constants.KustomizationFileNames[0], bytes)
 }
 
 func (fs *fakeFs) pathMatch(path, pattern string) bool {

pkg/loader/gitcloner_test.go

@@ -162,7 +162,7 @@ func TestGitLoader(t *testing.T) {
 	fSys.MkdirAll(coRoot)
 	fSys.MkdirAll(coRoot + "/" + pathInRepo)
 	fSys.WriteFile(
-		coRoot+"/"+pathInRepo+"/"+constants.KustomizationFileName,
+		coRoot+"/"+pathInRepo+"/"+constants.KustomizationFileNames[0],
 		[]byte(`
 whatever
 `))

pkg/target/kusttarget.go

@@ -82,18 +82,23 @@ func NewKustTarget(
 }
 
 func loadKustFile(ldr ifc.Loader) ([]byte, error) {
-	for _, kf := range []string{
-		constants.KustomizationFileName,
-		constants.SecondaryKustomizationFileName} {
-		content, err := ldr.Load(kf)
+	var content []byte
+	match := 0
+	for _, kf := range constants.KustomizationFileNames {
+		c, err := ldr.Load(kf)
 		if err == nil {
-			return content, nil
-		}
-		if !strings.Contains(err.Error(), "no such file or directory") {
-			return nil, err
+			match += 1
+			content = c
 		}
 	}
-	return nil, fmt.Errorf("no kustomization.yaml file under %s", ldr.Root())
+	switch match {
+	case 0:
+		return nil, fmt.Errorf("no kustomization.yaml file under %s", ldr.Root())
+	case 1:
+		return content, nil
+	default:
+		return nil, fmt.Errorf("Found multiple kustomization file under: %s\n", ldr.Root())
+	}
 }
 
 func unmarshal(y []byte, o interface{}) error {

pkg/target/utils_for_test.go

@@ -74,7 +74,7 @@ func (th *KustTestHarness) writeF(dir string, content string) {
 }
 
 func (th *KustTestHarness) writeK(dir string, content string) {
-	th.writeF(filepath.Join(dir, constants.KustomizationFileName), `
+	th.writeF(filepath.Join(dir, constants.KustomizationFileNames[0]), `
 apiVersion: v1beta1
 kind: Kustomization
 `+content)