Vertx, Scala Future example

mediumVertxScala.scala

  val vertx = Vertx.vertx()
  vertx.createHttpServer().requestHandler(req => {

    req.path() match {
      case p if p contains("/user") =>
        val f = for {
          f1 <- Future { req.getParam("id").get.toInt }
          f2 <- if (f1 < 100) Future.unit else Future.failed(CustomException())
          f3 <- Future { getUserFromDb(f1) }
        } yield f3
        f map (r => printout(req, r)) recover {case exception => printout(req, handleException(exception))}

      case _ => printout(req, "Default page")
    }

  })
  .listen(8080)

  def printout(req: HttpServerRequest, msg: String) = req.response().end(msg)

  def handleException(e: Throwable): String = {
    e match {
      case t: NoSuchElementException => "Missing parameter"
      case t: NumberFormatException => "Parameter not number"
      case t: CustomException => "Custom exception"
      case t: SQLException => "Database error" 
      case _ => "Unknown error"
    }
  }

  def getUserFromDb(id: Int) = "mock user name"

  case class CustomException() extends Exception("custom exception")