exposed Get/Set/Delete Internal methods

these are to be used to store side-channel information
along with the index

index.go

@@ -62,6 +62,10 @@ type Index interface {
 	Mapping() *IndexMapping
 
 	Stats() *IndexStat
+
+	GetInternal(key []byte) ([]byte, error)
+	SetInternal(key, val []byte) error
+	DeleteInternal(key []byte) error
 }
 
 // A Classifier is an interface describing any object

index_impl.go

@@ -533,3 +533,27 @@ func (i *indexImpl) Close() {
 func (i *indexImpl) Stats() *IndexStat {
 	return i.stats
 }
+
+func (i *indexImpl) GetInternal(key []byte) ([]byte, error) {
+	i.mutex.RLock()
+	defer i.mutex.RUnlock()
+
+	reader := i.i.Reader()
+	defer reader.Close()
+
+	return reader.GetInternal(key)
+}
+
+func (i *indexImpl) SetInternal(key, val []byte) error {
+	i.mutex.RLock()
+	defer i.mutex.RUnlock()
+
+	return i.i.SetInternal(key, val)
+}
+
+func (i *indexImpl) DeleteInternal(key []byte) error {
+	i.mutex.RLock()
+	defer i.mutex.RUnlock()
+
+	return i.i.DeleteInternal(key)
+}