akka-actors-cheatsheet.scala

// akka-actor cheatsheet
// extract from http://doc.akka.io/actors-scala

class MyActor extends Actor { // Logging is included in Actor
    // messages
    def receive = {
        case "foo" => 
            doBar
            
        case "logging" =>
            log.trace("trace msg")
            log.debug("debug msg")
            log.info("info msg")
            log.warn("warn msg")
            log.error("error msg")
            
        case "plz reply" =>
            self reply "success"
            
        case msg @ "plz forward me" =>
            otherActorRef forward msg
            
        case "plz start waiting" =>
            become(waitingForSomething)
            
        case msg =>
            log.warn("I dont know %s", msg)
            
    }
    
    // alternative receive
    def waitingForSomething: Receive = {
        case "go" => unbecome
    }
    
    // hooks
    
    override def preStart { } // when actor starting
    override def postStop { } // when invoking actor.stop
    override def preRestart(reason: Throwable) { } // when restarting by supervisor
    override def postRestart(reason: Throwable) { } // when restarting by supervisor
}

// Creating actors

val myActor = actorOf[MyActor].start
val myActor = actorOf(new MyActor("param")).start

// fire and forget, do not care about reply
myActor ! "msg"     


// Get response af future option
(myActor !! "msg") match {
    case Some(reply) => // handle reply
    case None        => // handle timeout
}


// Send and receive (see trait Future for docs)
myActor !!! "msg" 


// akka actor registry

// shutdown all
registry.shutdownAll

// find actors
registrt.actors: Array[ActorRef]
registry.actorFor[MyActor]: Option[ActorRef]
registry.actorsFor[MyActor]: Array[ActorRef]

registry.filter(p: (ActorRef) => Boolean): Array[ActorRef]
registry.find[T](f: PartialFunction[ActorRef, T]): Option[T]