diff --git a/src/main/scala/util/Validations.scala b/src/main/scala/util/Validations.scala
index 3b71280..0a1e9ef 100644
--- a/src/main/scala/util/Validations.scala
+++ b/src/main/scala/util/Validations.scala
@@ -9,7 +9,7 @@
    */
   def identifier: Constraint = new Constraint(){
     override def validate(name: String, value: String): Option[String] =
-      if(!value.matches("^[a-zA-Z0-9\\-_]+$")){
+      if(!value.matches("^[a-zA-Z0-9\\\\-_.]+$")){
         Some(s"${name} contains invalid character.")
       } else if(value.startsWith("_") || value.startsWith("-")){
         Some(s"${name} starts with invalid character.")