Steal Play2.0

both.scala

    val stealUserName = Intercept(
        r => Cache.getAs[String]("username").toSuccess(NonEmptyList("No username")), 
        (err, v:Failure[NonEmptyList[String], String]) => BadRequest(v.e.list.mkString("\n"))
    )
    val stealUserId = Intercept(
        r => Cache.getAs[String]("userid").map(_.toInt).toSuccess(NonEmptyList("No userid")), 
        (err, v:Failure[NonEmptyList[String], Int]) => BadRequest(v.e.list.mkString("\n"))
    )
    val stealUserNameAndId = Intercept(
        r => for {
            s1 <- stealUserName.steal(r);
            s2 <- stealUserId.steal(r)
        } yield (s1, s2), 
        (err, v:Failure[NonEmptyList[String], (String, Int)]) => BadRequest(v.e.list.mkString("\n"))
    )

bothAction.scala

    def both = stealUserNameAndId {case ((username, id)) => 
        Action {
            Ok(username + " " + id)
        }
    }

dummyMonoidComposition.scala

    val stealDummyString = Intercept(
        r => "dummy".success[NonEmptyList[String]], 
        (err, v:Failure[NonEmptyList[String], String]) => BadRequest(v.e.list.mkString("\n"))
    )


    def dummy = (stealUserName compose stealDummyString) {case usernameDummy => 
        Action {
            Ok(usernameDummy)
        }
    }

intercept.scala

case class Intercept[B] (
      steal: RequestHeader => ValidationNEL[String, B], 
      err: (RequestHeader, Failure[NonEmptyList[String], B]) => Result) extends Interceptor[B] {

}

interceptor.scala

trait Interceptor[B] {
  
  def steal: RequestHeader => ValidationNEL[String, B]
  def err: (RequestHeader, Failure[NonEmptyList[String], B]) => Result

  def apply[A](a: B => Action[A]): Action[(Action[A], A)] = {
     //[...]
  }
}