为什么我的路由器没有接收签入事件?

我开始探索新的Akka类型API。我正在试着运行随机路由器的更新版本 this blog post .

我的路由器基本上是一样的:

import java.util.concurrent.ThreadLocalRandom

import akka.actor.Address
import akka.actor.typed.{ActorRef, Behavior}
import akka.actor.typed.receptionist.{Receptionist, ServiceKey}
import akka.actor.typed.scaladsl.Behaviors
import akka.cluster.ClusterEvent.{ReachabilityEvent, ReachableMember, UnreachableMember}
import akka.cluster.typed.{Cluster, Subscribe}

object RandomRouter {
  private final case class WrappedReachabilityEvent(event: ReachabilityEvent)

  // subscribes to cluster reachability events and
  // avoids routees that are unreachable
  def clusterRouter[T](serviceKey: ServiceKey[T]): Behavior[T] =
    Behaviors.setup[Any] { ctx ⇒
      ctx.system.receptionist ! Receptionist.Subscribe(serviceKey, ctx.self)

      val cluster = Cluster(ctx.system)
      // typically you have to map such external messages into this
      // actor's protocol with a message adapter
      val reachabilityAdapter: ActorRef[ReachabilityEvent] = ctx.messageAdapter(WrappedReachabilityEvent.apply)

      cluster.subscriptions ! Subscribe(reachabilityAdapter, classOf[ReachabilityEvent])

      def routingBehavior(routees: Vector[ActorRef[T]], unreachable: Set[Address]): Behavior[Any] =
        Behaviors.receive { (ctx, msg) ⇒
          msg match {
            case serviceKey.Listing(services) ⇒
              if (services.isEmpty) {
                ctx.log.info("Found no services")
              } else {
                ctx.log.info(s"Found services: ${services.map(_.path.name).mkString(", ")}")
              }
              routingBehavior(services.toVector, unreachable)
            case WrappedReachabilityEvent(event) => event match {
              case UnreachableMember(m) =>
                ctx.log.warning(s"Member ${m.address} has become unreachable")
                routingBehavior(routees, unreachable + m.address)
              case ReachableMember(m) =>
                ctx.log.info(s"Member ${m.address} has become reachable again")
                routingBehavior(routees, unreachable - m.address)
            }

            case other: T @unchecked ⇒
              if (routees.isEmpty)
                Behaviors.unhandled
              else {
                val reachableRoutes =
                  if (unreachable.isEmpty) routees
                  else routees.filterNot { r => unreachable(r.path.address) }

                val i = ThreadLocalRandom.current.nextInt(reachableRoutes.size)
                reachableRoutes(i) ! other
                Behaviors.same
              }
          }
        }

      routingBehavior(Vector.empty, Set.empty)
    }.narrow[T]
}

我的集群由虚拟演员衍生:

object DummyActor {
  def behavior[T](serviceKey: ServiceKey[T]): Behavior[Any] = Behaviors.setup { ctx =>

    ctx.log.info("Woohoo, I'm alive!")
    Behaviors.empty
  }
}

以下是:

object MyCluster {

  val serviceKey: ServiceKey[String] = ServiceKey[String]("cluster")

  val behavior: Behavior[String] = Behaviors.setup { ctx =>

    (1 to 5).foreach { i =>
      ctx.log.info("I'm so sleepy...")
      Thread.sleep(500)
      ctx.log.info(s"Spawning actor #$i")
      ctx.spawnAnonymous(DummyActor.behavior(serviceKey))
      ctx.log.info("I'm tired again...")
      Thread.sleep(500)
    }

    val router = ctx.spawn(RandomRouter.clusterRouter(serviceKey), "router")

    Behaviors.stopped
  }
}

当我运行下面的main时,我总是在我的日志中看到“find no services”,这表明我认为没有一个虚拟参与者向集群接待员注册。

import akka.actor.typed.ActorSystem

object Main extends App {

  val system = ActorSystem(MyCluster.behavior, "cluster-system")

}

我错过了什么?我用的是Akka 2.5.12。