Akka/Scala example source code file (RemoteRouterConfig.scala)

This example Akka source code file (RemoteRouterConfig.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Akka and Scala source code examples by using tags.

All credit for the original source code belongs to akka.io; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Akka tags/keywords

actor, actorrefroutee, akka, deploy, iterable, iterator, pool, props, remote, remoterouterconfig, route, router, routeractor, routerconfig, routing, serialversionuid

The RemoteRouterConfig.scala Akka example source code

/**
 * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
 */
package akka.remote.routing

import akka.routing.Router
import akka.actor.Props
import akka.actor.ActorContext
import akka.routing.Routee
import java.util.concurrent.atomic.AtomicInteger
import akka.actor.Address
import akka.actor.ActorCell
import akka.actor.Deploy
import com.typesafe.config.ConfigFactory
import akka.routing.ActorRefRoutee
import akka.remote.RemoteScope
import akka.actor.Actor
import akka.actor.SupervisorStrategy
import akka.routing.Resizer
import akka.routing.RouterConfig
import akka.routing.Pool
import akka.actor.ActorSystem
import akka.routing.RouterActor
import akka.japi.Util.immutableSeq

/**
 * [[akka.routing.RouterConfig]] implementation for remote deployment on defined
 * target nodes. Delegates other duties to the local [[akka.routing.Pool]],
 * which makes it possible to mix this with the built-in routers such as
 * [[akka.routing.RoundRobinGroup]] or custom routers.
 */
@SerialVersionUID(1L)
final case class RemoteRouterConfig(local: Pool, nodes: Iterable[Address]) extends Pool {

  require(nodes.nonEmpty, "Must specify list of remote target.nodes")

  def this(local: Pool, nodes: java.lang.Iterable[Address]) = this(local, immutableSeq(nodes))
  def this(local: Pool, nodes: Array[Address]) = this(local, nodes: Iterable[Address])

  // need this iterator as instance variable since Resizer may call createRoutees several times
  @transient private val nodeAddressIter: Iterator[Address] = Stream.continually(nodes).flatten.iterator
  // need this counter as instance variable since Resizer may call createRoutees several times
  @transient private val childNameCounter = new AtomicInteger

  override def createRouter(system: ActorSystem): Router = local.createRouter(system)

  override def nrOfInstances: Int = local.nrOfInstances

  override def newRoutee(routeeProps: Props, context: ActorContext): Routee = {
    val name = "c" + childNameCounter.incrementAndGet
    val deploy = Deploy(config = ConfigFactory.empty(), routerConfig = routeeProps.routerConfig,
      scope = RemoteScope(nodeAddressIter.next))

    // attachChild means that the provider will treat this call as if possibly done out of the wrong
    // context and use RepointableActorRef instead of LocalActorRef. Seems like a slightly sub-optimal
    // choice in a corner case (and hence not worth fixing).
    val ref = context.asInstanceOf[ActorCell].attachChild(
      local.enrichWithPoolDispatcher(routeeProps, context).withDeploy(deploy), name, systemService = false)
    ActorRefRoutee(ref)
  }

  override def createRouterActor(): RouterActor = local.createRouterActor()

  override def supervisorStrategy: SupervisorStrategy = local.supervisorStrategy

  override def routerDispatcher: String = local.routerDispatcher

  override def resizer: Option[Resizer] = local.resizer

  override def withFallback(other: RouterConfig): RouterConfig = other match {
    case RemoteRouterConfig(local: RemoteRouterConfig, nodes) ⇒ throw new IllegalStateException(
      "RemoteRouterConfig is not allowed to wrap a RemoteRouterConfig")
    case RemoteRouterConfig(local: Pool, nodes) ⇒
      copy(local = this.local.withFallback(local).asInstanceOf[Pool])
    case _ ⇒ copy(local = this.local.withFallback(other).asInstanceOf[Pool])
  }

}