Initializing an actor before being able to handle some other messages

I have an actor which creates another one:

class MyActor1 extends Actor {
  val a2 = system actorOf Props(new MyActor(123))
}

The second actor must initialize (bootstrap) itself once it created and only after that it must be able to do other job.

class MyActor2(a: Int) extends Actor {
  //initialized (bootstrapped) itself, potentially a long operation 
  //how?
  val initValue = // get from a server

  //handle incoming messages
  def receive = {
    case "job1" => // do some job but after it's initialized (bootstrapped) itself
  }
}

So the very first thing MyActor2 must do is do some job of initializing itself. It might take some time because it's request to a server. Only after it finishes successfully, it must become able to handle incoming messages through receive. Before that - it must not do that.

Of course, a request to a server must be asynchronous (preferably, using Future, not async, await or other high level stuff like AsyncHttpClient). I know how to use Future, it's not a problem, though.

How do I ensure that?

p.s. My guess is that it must send a message to itself first.