There is no default timeout. A specific timeout value must be supplied to ask either by manually passing it in or by using an implicit val. In the second case, the implicit val may not necessarily appear in the same file where the ask is used, depending on what other namespaces the ask can see when it is being called.
I copied some code from Akka Cookbook that looks like follows
import akka.actor.{Actor, Props, ActorSystem}
import akka.pattern.ask
import akka.util.Timeout
import scala.concurrent.Await
import scala.concurrent.duration._
class FibonacciActor extends Actor {
override def receive: Receive = {
case num : Int =>
val fibonacciNumber = fib(num)
sender ! fibonacciNumber
}
def fib (n : Int) : Int = n match {
case 0 | 1 => n
case _ => fib(n-1) + fib(n-2)
}
}
object FibonacciActorApp extends App {
implicit val timeout = Timeout(3.seconds)
val actorSystem = ActorSystem("HelloAkka")
val actor = actorSystem.actorOf(Props[FibonacciActor])
val future = (actor ? 10).mapTo[Int]
val fibonacciNumber = Await.result(future, 10 seconds)
}
The code will not compile without a supplied Timeout value.
What is happening is that I am at work looking at some code that does not appear to supply a timeout in the same file where the ask is being called. The timeout appears as an implicit val in the larger namespace where my file is being called. So a timeout has to be supplied, but depending on the codebase, that timeout may not be in the same file where the ask is called. I found the place where the timeout appears by searching my codebase for all uses of the akka.util.Timeout class.
