inexplicable/akka-send-receive-with-context.scala

## akka-send-receive-with-context.scala
package com.example

import akka.actor.{ActorRef, Actor}
import spray.routing._
import spray.http._
import MediaTypes._

// we don't implement our route structure directly in the service actor because
// we want to be able to test it independently, without having to spin up an actor
class MyServiceActor extends MyService {

  // the HttpService trait defines only one abstract member, which
  // connects the services environment to the enclosing actor or test
  def actorRefFactory = context

  // this actor only runs our route, but you could add
  // other things here, like request stream processing
  // or timeout handling
  def receive = contextAwareReceive(runRoute(myRoute) orElse {
    case _ =>
      sender !! null
  })
}


// this trait defines our service behavior independently from the service actor
trait MyService extends HttpService with Actor {

  val myRoute =
    path("") {
      get {
        respondWithMediaType(`text/html`) { // XML is marshalled to `text/xml` by default, so we simply override here
          complete {
            <html>
              <body>
                <h1>Say hello to <i>spray-routing</i> on <i>spray-can</i>!</h1>
              </body>
            </html>
          }
        }
      }
    }

  implicit class ActorRefWithContext(actorRef:ActorRef) {

    def !! (msg:Any) = {
      actorRef ! msg
    }
  }

  type Context

  def contextAwareReceive(r: Actor.Receive):Actor.Receive = {

    case (ctx:Context, msg:Any) =>

      r(msg)
  }
}