This commit enhances the UnstructAdapter

* Added support for arbitrary data types rather than just strings
* Added support for integer index-able arrays
* Improve code coverage for kunstruct
  - kunstruct around 90%
  - helper at 100%
* Update expansion.Expand method to preserve the original type of the variable
* Ensure the int field such .spec.replicas can be used
  as a source in a first Deployment or as destination of a variable (in the
  second Deployment variable).

pkg/transformers/mutatefield_test.go

@@ -79,7 +79,7 @@ func makeTestDeployment() ifc.Kunstructured {
 }
 
 func getFieldValue(t *testing.T, obj ifc.Kunstructured, fieldName string) string {
-	v, err := obj.GetFieldValue(fieldName)
+	v, err := obj.GetString(fieldName)
 	if err != nil {
 		t.Fatalf("unexpected field error: %v", err)
 	}

pkg/transformers/refvars.go

@@ -24,17 +24,17 @@ import (
 )
 
 type RefVarTransformer struct {
-	varMap            map[string]string
+	varMap            map[string]interface{}
 	replacementCounts map[string]int
 	fieldSpecs        []config.FieldSpec
-	mappingFunc       func(string) string
+	mappingFunc       func(string) interface{}
 }
 
 // NewRefVarTransformer returns a new RefVarTransformer
 // that replaces $(VAR) style variables with values.
 // The fieldSpecs are the places to look for occurrences of $(VAR).
 func NewRefVarTransformer(
-	varMap map[string]string, fs []config.FieldSpec) *RefVarTransformer {
+	varMap map[string]interface{}, fs []config.FieldSpec) *RefVarTransformer {
 	return &RefVarTransformer{
 		varMap:     varMap,
 		fieldSpecs: fs,
@@ -48,7 +48,7 @@ func NewRefVarTransformer(
 func (rv *RefVarTransformer) replaceVars(in interface{}) (interface{}, error) {
 	switch vt := in.(type) {
 	case []interface{}:
-		var xs []string
+		var xs []interface{}
 		for _, a := range in.([]interface{}) {
 			xs = append(xs, expansion.Expand(a.(string), rv.mappingFunc))
 		}
@@ -59,16 +59,26 @@ func (rv *RefVarTransformer) replaceVars(in interface{}) (interface{}, error) {
 		for k, v := range inMap {
 			s, ok := v.(string)
 			if !ok {
-				return nil, fmt.Errorf("%#v is expected to be %T", v, s)
+				// This field not contain a $(VAR) since it is not
+				// of string type. For instance .spec.replicas: 3 in
+				// a Deployment object
+				xs[k] = v
+			} else {
+				// This field can potentially contains a $(VAR) since it is
+				// of string type. For instance .spec.replicas: $(REPLICAS)
+				// in a Deployment object
+				xs[k] = expansion.Expand(s, rv.mappingFunc)
 			}
-			xs[k] = expansion.Expand(s, rv.mappingFunc)
 		}
 		return xs, nil
 	case interface{}:
 		s, ok := in.(string)
 		if !ok {
-			return nil, fmt.Errorf("%#v is expected to be %T", in, s)
+			// This field not contain a $(VAR) since it is not of string type.
+			return in, nil
 		}
+		// This field can potentially contain a $(VAR) since it is
+		// of string type.
 		return expansion.Expand(s, rv.mappingFunc), nil
 	case nil:
 		return nil, nil

pkg/transformers/refvars_test.go

@@ -15,7 +15,7 @@ import (
 
 func TestVarRef(t *testing.T) {
 	type given struct {
-		varMap map[string]string
+		varMap map[string]interface{}
 		fs     []config.FieldSpec
 		res    resmap.ResMap
 	}
@@ -31,9 +31,11 @@ func TestVarRef(t *testing.T) {
 		{
 			description: "var replacement in map[string]",
 			given: given{
-				varMap: map[string]string{
+				varMap: map[string]interface{}{
 					"FOO": "replacementForFoo",
 					"BAR": "replacementForBar",
+					"BAZ": int64(5),
+					"BOO": true,
 				},
 				fs: []config.FieldSpec{
 					{Gvk: gvk.Gvk{Version: "v1", Kind: "ConfigMap"}, Path: "data"},
@@ -48,6 +50,10 @@ func TestVarRef(t *testing.T) {
 						"data": map[string]interface{}{
 							"item1": "$(FOO)",
 							"item2": "bla",
+							"item3": "$(BAZ)",
+							"item4": "$(BAZ)+$(BAZ)",
+							"item5": "$(BOO)",
+							"item6": "if $(BOO)",
 						},
 					}).ResMap(),
 			},
@@ -62,6 +68,10 @@ func TestVarRef(t *testing.T) {
 						"data": map[string]interface{}{
 							"item1": "replacementForFoo",
 							"item2": "bla",
+							"item3": int64(5),
+							"item4": "5+5",
+							"item5": true,
+							"item6": "if true",
 						}}).ResMap(),
 				unused: []string{"BAR"},
 			},