akka.io echo service test via fsharp

akkaio-fsharp-echotest.fs

open System
open System.Net
open Akka.Actor
open Akka.IO
open Akka.FSharp

let handle (message:obj) = 
  match message with
    | :? Tcp.Bound as bound -> 
      printfn "Listening on %A" bound.LocalAddress
    | :? Tcp.Connected as connected -> 
      printfn "New connection on %A" connected.LocalAddress
    | _ -> ()

// this will create a service whos Bound goes to deadletters and is not handled
// a connection can still be made to it though
let createEchoService1 (system:ActorSystem) =
  let echoService = spawn system "echo-service1" (actorOf handle)
  // rogeralsing:
  // in the first case, you are not inside the context of an actor, and thus, there is no Sender given to the <! operator
  // tell takes two arguments, message and sender. the last argument is optional and if you are inside an actor, Akka.NET will figure out who the current actor is and use that as sender
  //system.Tcp() <! Tcp.Bind(echoService, IPEndPoint(IPAddress.Any, 8001))
  system.Tcp().Tell(Tcp.Bind(echoService, IPEndPoint(IPAddress.Any, 8001)), echoService)
  echoService

// this seems fine
let createEchoService2 system =
  spawn system "echo-service2"
  <| fun mailbox ->
      mailbox.Context.System.Tcp() <! Tcp.Bind(mailbox.Self, IPEndPoint(IPAddress.Any, 8002))

      let rec loop() = actor {
        let! message = mailbox.Receive()
        handle message
        return! loop()
      }
      loop()

// this also seems fine
type EchoService() as self =
  inherit ReceiveActor()
  do 
    EchoService.Context.System.Tcp() <! Tcp.Bind(self.Self, IPEndPoint(IPAddress.Any, 8003))
    self.Receive<Tcp.Event>(handle)  

let createEchoService3 (system:ActorSystem) =
  system.ActorOf<EchoService>(name="echo-service3")


[<EntryPoint>]
let main argv = 
    use system = System.create "akkaio-test" <| Configuration.defaultConfig()
    let host1 = createEchoService1 system
    let host2 = createEchoService2 system
    let host3 = createEchoService3 system
    
    printfn "Press enter to exit"
    Console.ReadLine() |> ignore

    0