如何在 Akka 类型中从 ActorSystem 传递自我引用

Question

I am trying to get replies from the AKKA actor but i am able to get response with the Help of Ask method

object mainTest {

  val TestTypedSystem: ActorSystem[FuncTest.TypedFuncTest] = ActorSystem(FuncTest(),"FuncTest")

  implicit val sc: Scheduler = TestTypedSystem.scheduler

  implicit val ex: ExecutionContext = TestTypedSystem.executionContext

  import scala.concurrent.duration._

  import scala.language.postfixOps
  implicit val timeout: Timeout = Timeout(3 seconds)

  import FuncTest._

  //passing actorContext to the immutable Case class directly

  val testList = List (
    AskSomeoneTyped("Jay", 32, 'c',ActorRef[FuncTest.TypedFuncTest]),
    AskSomeoneTyped("Jay1", 32, 'a',ActorRef[FuncTest.TypedFuncTest]),
    AskSomeoneTyped("Jay2", 32, 'b',ActorRef[FuncTest.TypedFuncTest])
  )

  testList.foreach {
    player => TestTypedSystem ! TestaddSomeone(player)
  }

def main(args: Array[String]): Unit = {

 //Ask pattern to get responses by passing self context

 val sendingResp = TestTypedSystem.ask{
    f: ActorRef[FuncTest.TypedFuncTest] => AskSomeoneTyped("Jay",32,'c',f)
 }


  sendingResp.onComplete{
    case Success(value) => TestTypedSystem.log.info(s"Successfully completed : $value")
    case Failure(exception) => TestTypedSystem.log.warn(s"Got an exception $exception")

    }
  }
}

above Ask pattern from main method helps me get results back by passing 1 arg at a time but when using list.foreach I am not able to pass context of ActorSystem to get responses for a List of Actors.

messages are going to DeadLetters

Any Suggestions?

Answer 1

Still a lot of the code is missing, so I can't verify my answer. However, an educated guess would be:

The fourth argument of the each of the three case class instances in the list

val testList = List (
    AskSomeoneTyped("Jay", 32, 'c',ActorRef[FuncTest.TypedFuncTest]),
    AskSomeoneTyped("Jay1", 32, 'a',ActorRef[FuncTest.TypedFuncTest]),
    AskSomeoneTyped("Jay2", 32, 'b',ActorRef[FuncTest.TypedFuncTest])
  )

reference the type of the actor reference, not the actual actor references. If the behavior of FuncTest.apply() (missing in the above) tries to send a reply to these 'references', none will arive.

The problem is that the maintest object is not an actor, thus has no actor reference. Akka is not able to send it messages. Hence the f in the ask pattern

val sendingResp = TestTypedSystem.ask{
    f: ActorRef[FuncTest.TypedFuncTest] => AskSomeoneTyped("Jay",32,'c',f)
 }

which provides this reference. See the docs .

You might want to try something more along these lines:

case class Someone( name: String, age: Int, grade: Char)

val people = List (
    Someone("Jay",  32, 'c'),
    Someone("Jay1", 32, 'a'),
    Someone("Jay2", 32, 'b')
)

people.map{
    case Someone( name, age, grade ) => TestTypedSystem.ask( actorRef => AskSomeoneTyped( name, age, grade, actorRef ))
}.foreach( _.onComplete
{
    case Success(value) => TestTypedSystem.log.info(s"Successfully completed : $value")
    case Failure(exception) => TestTypedSystem.log.warn(s"Got an exception $exception")
})

Hope this helps.