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

This example Akka source code file (AskSpec.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, actorref, akka, akkaspec, asktimeout, asktimeoutexception, concurrent, failure, identify, left, test, testing, the, time, timeout, utilities

The AskSpec.scala Akka example source code

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

import language.postfixOps

import akka.actor._
import akka.testkit.AkkaSpec
import akka.util.Timeout
import scala.concurrent.Await
import scala.concurrent.duration._
import scala.util.Failure

class AskSpec extends AkkaSpec {

  "The “ask” pattern" must {

    "return broken promises on DeadLetters" in {
      implicit val timeout = Timeout(5 seconds)
      val dead = system.actorFor("/system/deadLetters")
      val f = dead.ask(42)(1 second)
      f.isCompleted should be(true)
      f.value.get match {
        case Failure(_: AskTimeoutException) ⇒
        case v                               ⇒ fail(v + " was not Left(AskTimeoutException)")
      }
    }

    "return broken promises on EmptyLocalActorRefs" in {
      implicit val timeout = Timeout(5 seconds)
      val empty = system.actorFor("unknown")
      val f = empty ? 3.14
      f.isCompleted should be(true)
      f.value.get match {
        case Failure(_: AskTimeoutException) ⇒
        case v                               ⇒ fail(v + " was not Left(AskTimeoutException)")
      }
    }

    "return broken promises on unsupported ActorRefs" in {
      implicit val timeout = Timeout(5 seconds)
      val f = ask(null: ActorRef, 3.14)
      f.isCompleted should be(true)
      intercept[IllegalArgumentException] {
        Await.result(f, timeout.duration)
      }.getMessage should be("Unsupported recipient ActorRef type, question not sent to [null]")
    }

    "return broken promises on 0 timeout" in {
      implicit val timeout = Timeout(0 seconds)
      val echo = system.actorOf(Props(new Actor { def receive = { case x ⇒ sender() ! x } }))
      val f = echo ? "foo"
      val expectedMsg = "Timeout length must not be negative, question not sent to [%s]" format echo
      intercept[IllegalArgumentException] {
        Await.result(f, timeout.duration)
      }.getMessage should be(expectedMsg)
    }

    "return broken promises on < 0 timeout" in {
      implicit val timeout = Timeout(-1000 seconds)
      val echo = system.actorOf(Props(new Actor { def receive = { case x ⇒ sender() ! x } }))
      val f = echo ? "foo"
      val expectedMsg = "Timeout length must not be negative, question not sent to [%s]" format echo
      intercept[IllegalArgumentException] {
        Await.result(f, timeout.duration)
      }.getMessage should be(expectedMsg)
    }

    "include target information in AskTimeout" in {
      implicit val timeout = Timeout(0.5 seconds)
      val silentOne = system.actorOf(Props.empty, "silent")
      val f = silentOne ? "noreply"
      intercept[AskTimeoutException] {
        Await.result(f, 1 second)
      }.getMessage.contains("/user/silent") should be(true)
    }

    "include timeout information in AskTimeout" in {
      implicit val timeout = Timeout(0.5 seconds)
      val f = system.actorOf(Props.empty) ? "noreply"
      intercept[AskTimeoutException] {
        Await.result(f, 1 second)
      }.getMessage should include(timeout.duration.toMillis.toString)
    }

    "work for ActorSelection" in {
      implicit val timeout = Timeout(5 seconds)
      import system.dispatcher
      val echo = system.actorOf(Props(new Actor { def receive = { case x ⇒ sender() ! x } }), "select-echo")
      val identityFuture = (system.actorSelection("/user/select-echo") ? Identify(None))
        .mapTo[ActorIdentity].map(_.ref.get)

      Await.result(identityFuture, 5 seconds) should be(echo)
    }

  }

}