Check for config merge conflicts and duplication.

pkg/transformers/config/transformerconfig.go

@@ -44,43 +44,70 @@ func (t *TransformerConfig) sortFields() {
 }
 
 // AddPrefixFieldSpec adds a FieldSpec to NamePrefix
-func (t *TransformerConfig) AddPrefixFieldSpec(fs FieldSpec) {
-	t.NamePrefix = append(t.NamePrefix, fs)
+func (t *TransformerConfig) AddPrefixFieldSpec(fs FieldSpec) (err error) {
+	t.NamePrefix, err = t.NamePrefix.mergeOne(fs)
+	return err
 }
 
 // AddSuffixFieldSpec adds a FieldSpec to NameSuffix
-func (t *TransformerConfig) AddSuffixFieldSpec(fs FieldSpec) {
-	t.NameSuffix = append([]FieldSpec{fs}, t.NameSuffix...)
+func (t *TransformerConfig) AddSuffixFieldSpec(fs FieldSpec) (err error) {
+	t.NameSuffix, err = t.NameSuffix.mergeOne(fs)
+	return err
 }
 
 // AddLabelFieldSpec adds a FieldSpec to CommonLabels
-func (t *TransformerConfig) AddLabelFieldSpec(fs FieldSpec) {
-	t.CommonLabels = append(t.CommonLabels, fs)
+func (t *TransformerConfig) AddLabelFieldSpec(fs FieldSpec) (err error) {
+	t.CommonLabels, err = t.CommonLabels.mergeOne(fs)
+	return err
 }
 
 // AddAnnotationFieldSpec adds a FieldSpec to CommonAnnotations
-func (t *TransformerConfig) AddAnnotationFieldSpec(fs FieldSpec) {
-	t.CommonAnnotations = append(t.CommonAnnotations, fs)
+func (t *TransformerConfig) AddAnnotationFieldSpec(fs FieldSpec) (err error) {
+	t.CommonAnnotations, err = t.CommonAnnotations.mergeOne(fs)
+	return err
 }
 
 // AddNamereferenceFieldSpec adds a NameBackReferences to NameReference
-func (t *TransformerConfig) AddNamereferenceFieldSpec(nbrs NameBackReferences) {
-	t.NameReference = t.NameReference.mergeOne(nbrs)
+func (t *TransformerConfig) AddNamereferenceFieldSpec(nbrs NameBackReferences) (err error) {
+	t.NameReference, err = t.NameReference.mergeOne(nbrs)
+	return err
 }
 
 // Merge merges two TransformerConfigs objects into a new TransformerConfig object
-func (t *TransformerConfig) Merge(input *TransformerConfig) *TransformerConfig {
+func (t *TransformerConfig) Merge(input *TransformerConfig) (
+	merged *TransformerConfig, err error) {
 	if input == nil {
-		return t
+		return t, nil
+	}
+	merged = &TransformerConfig{}
+	merged.NamePrefix, err = t.NamePrefix.mergeAll(input.NamePrefix)
+	if err != nil {
+		return nil, err
+	}
+	merged.NameSuffix, err = t.NameSuffix.mergeAll(input.NameSuffix)
+	if err != nil {
+		return nil, err
+	}
+	merged.NameSpace, err = t.NameSpace.mergeAll(input.NameSpace)
+	if err != nil {
+		return nil, err
+	}
+	merged.CommonAnnotations, err = t.CommonAnnotations.mergeAll(input.CommonAnnotations)
+	if err != nil {
+		return nil, err
+	}
+	merged.CommonLabels, err = t.CommonLabels.mergeAll(input.CommonLabels)
+	if err != nil {
+		return nil, err
+	}
+	merged.VarReference, err = t.VarReference.mergeAll(input.VarReference)
+	if err != nil {
+		return nil, err
+	}
+	merged.NameReference, err = t.NameReference.mergeAll(input.NameReference)
+	if err != nil {
+		return nil, err
 	}
-	merged := &TransformerConfig{}
-	merged.NamePrefix = append(t.NamePrefix, input.NamePrefix...)
-	merged.NameSuffix = append(input.NameSuffix, t.NameSuffix...)
-	merged.NameSpace = append(t.NameSpace, input.NameSpace...)
-	merged.CommonAnnotations = append(t.CommonAnnotations, input.CommonAnnotations...)
-	merged.CommonLabels = append(t.CommonLabels, input.CommonLabels...)
-	merged.VarReference = append(t.VarReference, input.VarReference...)
-	merged.NameReference = t.NameReference.mergeAll(input.NameReference)
 	merged.sortFields()
-	return merged
+	return merged, nil
 }