Testkit support (or examples) for Akka Typed

[chbatey]

RouteTest has a field system that has an untyped ActorSystem and ActorTestKit has a field system that is a typed ActorSystem so they can't be used together.

Perhaps just a docs addition to show that you don't need to use the ActorTestKit from Akka Typed and can just use TestProbes e.g. https://gist.github.com/chbatey/964b80adc2cd124fa4bf4624927b5be0

[jlprat]

I think it makes sense to add this one to the docs

[babloo80]

Here is what I did (perhaps naive)...

import akka.actor.{ActorSystem, Scheduler}
import akka.actor.testkit.typed.scaladsl.{ActorTestKit, ActorTestKitBase}
import akka.http.scaladsl.testkit.ScalatestRouteTest
import org.scalatest.Suite
import akka.util.Timeout

trait ScalatestTypedActorHttpRoute extends ScalatestRouteTest { this: Suite =>
  import akka.actor.typed.scaladsl.adapter._

  var typedTestKit:ActorTestKit = _ //val init causes createActorSystem() to cause NPE when typedTestKit.system is called in createActorSystem().
  implicit def timeout: Timeout = typedTestKit.timeout
  implicit def scheduler: Scheduler = typedTestKit.scheduler

  protected override def createActorSystem(): ActorSystem = {
    typedTestKit = ActorTestKit(ActorTestKitBase.testNameFromCallStack())
    typedTestKit.system.toUntyped
  }

  override def cleanUp(): Unit = {
    super.cleanUp()
    typedTestKit.shutdownTestKit()
  }
}

In the test itself...

class TokenLookupServiceWSSpec extends FlatSpec with Matchers with ScalatestTypedActorHttpRoute {
  implicit val mat: ActorMaterializer = ActorMaterializer()
  val wsClient = WSProbe()
  val typedActorRef = typedTestKit.spawn(SomeUsefulTypedActor())
 
  "test with WS" should "be handled correctly" in {
    WS("/ws", wsClient.flow) ~> myroute(typedActorRef) ~>
    check {
      wsClient.sendMessage(newTokenCreationRequest)
       toJSON(wsClient.expectMessage()) shouldBe(someThingUseful())
    }
  } 
}

[raboof]

Added examples in #3496. It might still be nice to improve the API support for this, but let's track that in a separate ticket.