How to handle lifecycle signal with Behavior.receiveMessage

Akka
1

Hi all

I have an actor, that is created as follows:

    Behaviors.setup { context =>
          val greeter = context.spawn(HelloWorld.greeter, "greeter")

          Behaviors.receiveMessage { message =>
            val replyTo = context.spawn(HelloWorldBot.bot(greetingCounter = 0, max = 3), message.name)
            greeter ! HelloWorld.Greet(message.name, replyTo)
            Behaviors.same
          }
        }

I would like to handle Signals messages(for example PostStop) within the Behaviors.receiveMessage and in the doc says:

Simplified version of Receive with only a single argument - the message to be handled. Useful for when the context is already accessible by other means, like being wrapped in an setup or similar. Construct an actor behavior that can react to both incoming messages and lifecycle signals. After spawning this actor from another actor (or as the guardian of an akka.actor.typed.ActorSystem) it will be executed within an ActorContext that allows access to the system, spawning and watching other actors, etc. Compared to using AbstractBehavior this factory is a more functional style of defining the Behavior. Processing the next message results in a new behavior that can potentially be different from this one. State is maintained by returning a new behavior that holds the new immutable state.

But how to implement the lifecycle Signals within the Behaviors.receiveMessage ?

Here is the link to the doc Akka 2.9.0 - akka.actor.typed.scaladsl.Behaviors

Thanks

2

You can chain the Behaviors.receiveMessage with .receiveSignal.

          Behaviors.receiveMessage[Greet] { message =>
            val replyTo = context.spawn(HelloWorldBot.bot(greetingCounter = 0, max = 3), message.name)
            greeter ! HelloWorld.Greet(message.name, replyTo)
            Behaviors.same
          }
          .receiveSignal {
            case (context, PostStop) =>
              context.log.info("stopped")
              Behaviors.same
        }

Due to the chained methods you might have to give the compiler an additional type hint in the Behaviors.receiveMessage[Greet] { message =>

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