小编wer*_*erb的帖子

我试图在scala中使用spray-json来识别转换为Json和返回时Ec2Provider和OpenstackProvider之间的选择.我希望能够在"提供者"中做出选择,如果这些选择不符合可用的选择,那么它就不应该验证.

我在这方面的尝试可以在以下代码中看到:

import spray.json._
import DefaultJsonProtocol._ 

case class Credentials(username: String, password: String)
abstract class Provider
case class Ec2Provider(endpoint: String,credentials: Credentials) extends Provider
case class OpenstackProvider(credentials: Credentials) extends Provider
case class Infrastructure(name: String, provider: Provider, availableInstanceTypes: List[String])
case class InfrastructuresList(infrastructures: List[Infrastructure])

object Infrastructures extends App with DefaultJsonProtocol {
   implicit val credFormat = jsonFormat2(Credentials)
   implicit val ec2Provider = jsonFormat2(Ec2Provider)
   implicit val novaProvider = jsonFormat1(OpenstackProvider)
   implicit val infraFormat = jsonFormat3(Infrastructure)
   implicit val infrasFormat = jsonFormat1(InfrastructuresList)

  println(
    InfrastructuresList(
      List(
        Infrastructure("test", Ec2Provider("nova", Credentials("user","pass")), List("1", "2")) …