Wildcard support for creation in ReplacementTransformer

api/filters/replacement/replacement.go

@@ -179,63 +179,38 @@ func rejectId(rejects []*types.Selector, id *resid.ResId) bool {
 
 func copyValueToTarget(target *yaml.RNode, value *yaml.RNode, selector *types.TargetSelector) error {
 	for _, fp := range selector.FieldPaths {
-		mutator := updateMatchingFields
+		createKind := yaml.Kind(0) // do not create
 		if selector.Options != nil && selector.Options.Create {
-			mutator = createOrUpdateOneField
+			createKind = value.YNode().Kind
 		}
-		if err := mutator(target, value, selector.Options, fp); err != nil {
-			return err
+		targetFieldList, err := target.Pipe(&yaml.PathMatcher{
+			Path:   kyaml_utils.SmarterPathSplitter(fp, "."),
+			Create: createKind})
+		if err != nil {
+			return errors.WrapPrefixf(err, fieldRetrievalError(fp, createKind != 0))
+		}
+		targetFields, err := targetFieldList.Elements()
+		if err != nil {
+			return errors.WrapPrefixf(err, fieldRetrievalError(fp, createKind != 0))
+		}
+		if len(targetFields) == 0 {
+			return errors.Errorf(fieldRetrievalError(fp, createKind != 0))
 		}
-	}
-	return nil
-}
-
-// updateMatchingFields updates all fields in target that match the given field path.
-// If the field path does not already exist in the target, an error is returned.
-func updateMatchingFields(target *yaml.RNode, value *yaml.RNode, opts *types.FieldOptions, fp string) error {
-	fieldPath := kyaml_utils.SmarterPathSplitter(fp, ".")
-	// may return multiple fields, always wrapped in a sequence node
-	foundFieldSequence, lookupErr := target.Pipe(&yaml.PathMatcher{Path: fieldPath})
-	if lookupErr != nil {
-		return fmt.Errorf("error finding field in replacement target: %w", lookupErr)
-	}
-	targetFields, err := foundFieldSequence.Elements()
-	if err != nil {
-		return fmt.Errorf("error fetching elements in replacement target: %w", err)
-	}
-	if len(targetFields) == 0 {
-		return errors.Errorf("unable to find field %s in replacement target", fp)
-	}
 
-	for _, t := range targetFields {
-		if err := setFieldValue(opts, t, value); err != nil {
-			return err
+		for _, t := range targetFields {
+			if err := setFieldValue(selector.Options, t, value); err != nil {
+				return err
+			}
 		}
 	}
 	return nil
 }
 
-// createOrUpdateOneField updates the field in the target that matches the given field path.
-// If the field path does not already exist in the target, it is created.
-// Wildcard matching is not supported, nor is creating intermediate list nodes.
-func createOrUpdateOneField(target *yaml.RNode, value *yaml.RNode, opts *types.FieldOptions, fp string) error {
-	fieldPath := kyaml_utils.SmarterPathSplitter(fp, ".")
-	for _, f := range fieldPath {
-		if f == "*" {
-			return fmt.Errorf("cannot support create option in a multi-value target")
-		}
+func fieldRetrievalError(fieldPath string, isCreate bool) string {
+	if isCreate {
+		return "unable to find or create field " + fieldPath + " in replacement target"
 	}
-	createdField, createErr := target.Pipe(yaml.LookupCreate(value.YNode().Kind, fieldPath...))
-	if createErr != nil {
-		return fmt.Errorf("error creating replacement node: %w", createErr)
-	}
-	if createdField == nil {
-		return errors.Errorf("unable to find or create field %s in replacement target", fp)
-	}
-	if err := setFieldValue(opts, createdField, value); err != nil {
-		return errors.WrapPrefixf(err, "unable to set field %s in replacement target", fp)
-	}
-	return nil
+	return "unable to find field " + fieldPath + " in replacement target"
 }
 
 func setFieldValue(options *types.FieldOptions, targetField *yaml.RNode, value *yaml.RNode) error {