An example of using a simple http server using a sprayer, how are related messages handled?

Question

In the example of an HTTP server with a sprayer, when I start the server, I do not see the message “Connected” in the log file:

https://github.com/spray/spray/tree/master/examples/spray-can/simple-http-server/src/main

However, if I try to create my own server and ignore the Bound message, I get them to the dead letters:

 $ sbt run [info] Set current project to pingpong (in build file:/D:/Projects/pingpong/) [info] Updating {file:/D:/Projects/pingpong/}pingpong... [info] Resolving jline#jline;2.12.1 ... [info] Done updating. [info] Running drozdyuk.pingpong.Main [INFO] [08/03/2015 20:05:47.246] [default-akka.actor.default-dispatcher-2] [akka ://default/user/IO-HTTP/listener-0] Bound to localhost/127.0.0.1:8081 [INFO] [08/03/2015 20:05:47.246] [default-akka.actor.default-dispatcher-2] [akka ://default/deadLetters] Message [akka.io.Tcp$Bound] from Actor[akka://default/us er/IO-HTTP/listener-0#-892116855] to Actor[akka://default/deadLetters] was not d elivered. [1] dead letters encountered. This logging can be turned off or adjust ed with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letter s-during-shutdown'. 

My question is mainly out of curiosity, how is the Bound message handled in the example? Is it some kind of magazine that swallows them or something else?

Code for my Main.scala :

 package drozdyuk.pingpong import akka.actor.{ActorSystem, Props} import akka.io.IO import spray.can.Http object Main extends App { implicit val system = ActorSystem() // the handler actor replies to incoming HttpRequests val handler = system.actorOf(Props[WebService], name = "handler") val PORT = 8081 val DOMAIN = "localhost" IO(Http) ! Http.Bind(handler, interface = DOMAIN, port = PORT) } 

and my WebService.scala :

 package drozdyuk.pingpong import akka.actor._ import spray.http.HttpMethods.{GET} import spray.can.Http import spray.http.{HttpRequest, HttpResponse, Uri} class WebService extends Actor with ActorLogging { def receive = { // New connection - register self as handler case _: Http.Connected => sender ! Http.Register(self) case HttpRequest(GET, Uri.Path("/ping"), _, _, _) => sender ! HttpResponse(entity = "pong") case HttpRequest(GET, Uri.Path("/pong"), _, _, _) => sender ! HttpResponse(entity = "ping") case _: HttpRequest => sender ! HttpResponse(status = 404, entity = "Unknown resource!") } } 

Answer 1

You can use a different version of tell in your Main :

 IO(Http).tell(Http.Bind(handler, interface = DOMAIN, port = PORT), sender = handler) 

And then process the Bound message in your WebService:

 class WebService extends Actor with ActorLogging { def receive = { case Http.Bound(address) => //all other cases... } } 

In your case you use

 def !(message: Any)(implicit sender: ActorRef = Actor.noSender): Unit 

and there is no implicit sender in the Main , so the default value of noSender will be used.

Answer 2

I tried this and it works great for me:

 import akka.actor._ import akka.io._ import spray.can.Http import spray.http.HttpResponse import spray.http.HttpRequest import spray.http.Uri import spray.http.HttpMethods.{GET} class WebService extends Actor with ActorLogging { def receive = { case _: Http.Connected => sender ! Http.Register(self) case _: HttpRequest => sender ! HttpResponse(status = 404, entity = "Unknown resource!") case HttpRequest(GET, Uri.Path("/ping"), _, _, _) => sender ! HttpResponse(entity = "pong") //all other cases... } } object TestSpray extends App { implicit val system = ActorSystem() val myListener: ActorRef = system.actorOf(Props[WebService], name = "handler") IO(Http) ! Http.Bind(myListener, interface = "localhost", port = 8080) }