Question: How to wait in a Main method of a console app till an actor is done with its job?

[o7g8]

Hello,

I'm coding a console application which process data from stdin with actors: I have a manager actor and workers spawned and coordinated by the manager.

Here is a snippet from my Main() method:

var actorSystem = ActorSystem.Create("mysys");
var manager = actorSystem.ActorOf(Props.Create<Manager>(), "manager");

var line = Console.In.ReadLine();
while(line != null) {
    manager.Tell(new ProcessLine(line));
    var line = Console.In.ReadLine();
}

// QUESTION: how do I wait here till the `manager` is done with its job before I terminate the program?

My question is how do I wait in the Main() method till manager actor is done with it's job?
And what is the proper way for the manager actor to signal the Main() method about the fact that the processing is done and the program can terminate?

Thank you in advance!

[o7g8]

I decided to use a Barrier to wait on the manager actor:

var allWorkDone = new Barrier(2);
var actorSystem = ActorSystem.Create("mysys");
var manager = actorSystem.ActorOf(Props.Create<Manager>(allWorkDone), "manager");

var line = Console.In.ReadLine();
while(line != null) {
    manager.Tell(new ProcessLine(line));
    var line = Console.In.ReadLine();
}

allWorkDone.SignalAndWait(); // wait till the `manager` actor calls allWorkDone.SignalAndWait() too
// termination procedures

When manager detect that all work is done, it calls allWorkDone.SignalAndWait() as well.

[coldwarrl]

You can use Ask instead of Tell to wait for a response (of crs your manager actor shall then send a reply back when the process is finished)

var task = manager.Ask(message);
task.Wait();

[to11mtm]

To mix these two together...

var actorSystem = ActorSystem.Create("mysys");
var manager = actorSystem.ActorOf(Props.Create<Manager>(), "manager");

var line = Console.In.ReadLine();
while(line != null) {
    manager.Tell(new ProcessLine(line));
    var line = Console.In.ReadLine();
}
// Have manager respond to DoneMarker with some message
// It will process after all previous tells were completed,
// So when this await finishes you know it processed
// Everything else.
await manager.Ask(new DoneMarker());

[Aaronontheweb]

@Arkatufus would the new Startup task in Akka.Hosting be a good fit for this?