模拟演员及其在单元测试中的反应

Question

我有一个在 actor 内部启动的 actor，我想模拟 actorB 这样消息演员B？ GetDataForProcessing(value) 未发送到 actorB，我可以测试 ActorExp 的单元功能。

我的演员是：

class ActorExp(a: ARepo) extends Actor{

  lazy val actorB = context.system.actorSelection("user/ActorB")

  def receive: Receive = {

    case m @ GetData(value) =>
          sender() ! getData(value)
  }

  def getData(value:String) = {
    val res = actorB ? GetDataForProcessing(value)
    res map {
           ...
    }
  }
}

class ActorB(repoB: BRepo) extends Actor{...}

我正在尝试编写的测试是：

class ActorExpSpecSpec
        extends TestKit(ActorSystem("ActorExpSpecSpec"))
        with WordSpecLike
        with Matchers
        with JsonSupport
        with MockitoSugar
        with BeforeAndAfterAll
        with ImplicitSender {
  override def afterAll: Unit = TestKit.shutdownActorSystem(system)

  implicit val futureDuration: FiniteDuration = 60.seconds
  implicit val timeout: Timeout               = 10.seconds
  val mockedRepoA                       = mock[ARepo]

  val actorA: ActorRef                  = TestActorRef(ActorExp.props(mockedRepoA))

  "ActorExpSpecSpec" should {
    "be able to data" in {

      val action = (actorA ? GetData("value")).mapTo[Seq[String]]
      val result = Await.result(action, 10.seconds)
      result should equal("yes")
    } 
  }
}

现在我收到询问超时异常，因为 actorB 未初始化，因为它需要某些参数，我不想测试 actorB。在上述场景中有什么方法可以模拟 actorB 及其消息 actorB ? GetDataForProcessing(value)?

Answer 1

向 ActorExp 添加额外的构造函数参数，定义演员选择路径 user/ActorB 并在您的测试表单中提供它 TestProbe().ref.path

这里有一些简化的例子：

  class ParentActor(actorPath: String) extends Actor {

    private val selected = context.system.actorSelection(actorPath)

    override def receive: Receive = {
      case msg: String =>
        val replyTo = sender()
        //some irrelevant logic to test
        (selected ? msg).mapTo[String].onComplete {
          case Success(v)  => replyTo ! v
          case Failure(ex) => throw ex
        }
    }
  }

现在，您可以在测试时像这样提供 TestProbe 进入您的 actor 的路径。

val testProbe = TestProbe()
val actor = system.actorOf(
  Props(new ParentActor(testProbe.ref.path.toStringWithoutAddress))
)
val reply = actor ? "Hello"
testProbe.expectMsg("Hello")
testProbe.reply("Hi")
reply.map { res =>
  assert(res == "Hi")
}

模拟演员及其在单元测试中的反应

Mock actor and its response in unit test

scala

mocking

akka

scalatest

akka-testkit