Gather and use some of the kyaml constants.

kyaml/yaml/const.go

@@ -0,0 +1,29 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package yaml
+
+const (
+	// NodeTagNull is the tag set for a yaml.Document that contains no data;
+	// e.g. it isn't a Map, Slice, Document, etc
+	NodeTagNull   = "!!null"
+	NodeTagFloat  = "!!float"
+	NodeTagString = "!!str"
+	NodeTagBool   = "!!bool"
+	NodeTagInt    = "!!int"
+	NodeTagMap    = "!!map"
+	NodeTagSeq    = "!!seq"
+	NodeTagEmpty  = ""
+)
+
+// Field names
+const (
+	AnnotationsField = "annotations"
+	APIVersionField  = "apiVersion"
+	KindField        = "kind"
+	MetadataField    = "metadata"
+	DataField        = "data"
+	NameField        = "name"
+	NamespaceField   = "namespace"
+	LabelsField      = "labels"
+)

kyaml/yaml/kfns.go

@@ -17,7 +17,7 @@ type AnnotationClearer struct {
 
 func (c AnnotationClearer) Filter(rn *RNode) (*RNode, error) {
 	return rn.Pipe(
-		PathGetter{Path: []string{"metadata", "annotations"}},
+		PathGetter{Path: []string{MetadataField, AnnotationsField}},
 		FieldClearer{Name: c.Key})
 }
 
@@ -28,12 +28,12 @@ func ClearAnnotation(key string) AnnotationClearer {
 // ClearEmptyAnnotations clears the keys, annotations
 // and metadata if they are empty/null
 func ClearEmptyAnnotations(rn *RNode) error {
-	_, err := rn.Pipe(Lookup("metadata"), FieldClearer{
+	_, err := rn.Pipe(Lookup(MetadataField), FieldClearer{
-		Name: "annotations", IfEmpty: true})
+		Name: AnnotationsField, IfEmpty: true})
 	if err != nil {
 		return errors.Wrap(err)
 	}
-	_, err = rn.Pipe(FieldClearer{Name: "metadata", IfEmpty: true})
+	_, err = rn.Pipe(FieldClearer{Name: MetadataField, IfEmpty: true})
 	if err != nil {
 		return errors.Wrap(err)
 	}
@@ -59,7 +59,9 @@ func (s AnnotationSetter) Filter(rn *RNode) (*RNode, error) {
 	}
 
 	return rn.Pipe(
-		PathGetter{Path: []string{"metadata", "annotations"}, Create: yaml.MappingNode},
+		PathGetter{
+			Path: []string{MetadataField, AnnotationsField},
+			Create: yaml.MappingNode},
 		FieldSetter{Name: s.Key, Value: v})
 }
 
@@ -78,7 +80,8 @@ type AnnotationGetter struct {
 // AnnotationGetter returns the annotation value.
 // Returns "", nil if the annotation does not exist.
 func (g AnnotationGetter) Filter(rn *RNode) (*RNode, error) {
-	v, err := rn.Pipe(PathGetter{Path: []string{"metadata", "annotations", g.Key}})
+	v, err := rn.Pipe(
+		PathGetter{Path: []string{MetadataField, AnnotationsField, g.Key}})
 	if v == nil || err != nil {
 		return v, err
 	}
@@ -106,7 +109,8 @@ func (s LabelSetter) Filter(rn *RNode) (*RNode, error) {
 	v.YNode().Tag = NodeTagString
 	v.YNode().Style = yaml.SingleQuotedStyle
 	return rn.Pipe(
-		PathGetter{Path: []string{"metadata", "labels"}, Create: yaml.MappingNode},
+		PathGetter{
+			Path: []string{MetadataField, LabelsField}, Create: yaml.MappingNode},
 		FieldSetter{Name: s.Key, Value: v})
 }
 

kyaml/yaml/kfns_test.go

@@ -16,7 +16,7 @@ data:
   enableRisky: "false"
 `
 
-func TestSetLabel(t *testing.T) {
+func TestSetLabel1(t *testing.T) {
 	rn := MustParse(input)
 	_, err := rn.Pipe(SetLabel("foo", "bar"))
 	if err != nil {
@@ -39,6 +39,31 @@ data:
 	}
 }
 
+func TestSetLabel2(t *testing.T) {
+	rn := MustParse(`apiVersion: v1
+kind: ConfigMap
+data:
+  altGreeting: "Good Morning!"
+`)
+	_, err := rn.Pipe(SetLabel("foo", "bar"))
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	output := rn.MustString()
+
+	expected := `apiVersion: v1
+kind: ConfigMap
+data:
+  altGreeting: "Good Morning!"
+metadata:
+  labels:
+    foo: 'bar'
+`
+	if output != expected {
+		t.Fatalf("expected \n%s\nbut got \n%s\n", expected, output)
+	}
+}
+
 func TestAnnotation(t *testing.T) {
 	rn := MustParse(input)
 	_, err := rn.Pipe(SetAnnotation("foo", "bar"))

kyaml/yaml/rnode.go

@@ -14,18 +14,6 @@ import (
 	"sigs.k8s.io/kustomize/kyaml/errors"
 )
 
-const (
-	// NodeTagNull is the tag set for a yaml.Document that contains no data;
-	// e.g. it isn't a Map, Slice, Document, etc
-	NodeTagNull   = "!!null"
-	NodeTagFloat  = "!!float"
-	NodeTagString = "!!str"
-	NodeTagBool   = "!!bool"
-	NodeTagInt    = "!!int"
-	NodeTagMap    = "!!map"
-	NodeTagSeq    = "!!seq"
-	NodeTagEmpty  = ""
-)
 
 // MakeNullNode returns an RNode that represents an empty document.
 func MakeNullNode() *RNode {
@@ -184,17 +172,6 @@ func (rn *RNode) Copy() *RNode {
 
 var ErrMissingMetadata = fmt.Errorf("missing Resource metadata")
 
-// Field names
-const (
-	AnnotationsField = "annotations"
-	APIVersionField  = "apiVersion"
-	KindField        = "kind"
-	MetadataField    = "metadata"
-	NameField        = "name"
-	NamespaceField   = "namespace"
-	LabelsField      = "labels"
-)
-
 // IsNil is true if the node is nil, or its underlying YNode is nil.
 func (rn *RNode) IsNil() bool {
 	return rn == nil || rn.YNode() == nil