Identifier: New functions to create from string and know if empty

model/identifier.go

@@ -5,8 +5,18 @@ import (
 	"errors"
 )
 
+const IDENTIFIER_LEN = 48
+
 type Identifier []byte
 
+func NewIdentifierFromString(src string) (id Identifier, err error) {
+	return base64.RawURLEncoding.DecodeString(src)
+}
+
+func (i *Identifier) IsEmpty() bool {
+	return len(*i) == 0
+}
+
 func (i *Identifier) ToString() string {
 	return base64.RawURLEncoding.EncodeToString(*i)
 }