docker akka and scala, app start and stop just after without reason - scala

Question

I created a scala App using Akka.
When i run it with : scala /Statistics.jar ./server.conf it works perfectly.
but if I put it in a server or if I put it in a docker image, when i launch it the app start then stop directly after.
Here are my logs :
...
[DEBUG] [02/01/2017 10:26:13.198] [webserver-akka.actor.default-dispatcher-11] [EventStream(akka://version)] logger log1-Slf4jLogger started
[DEBUG] [02/01/2017 10:26:13.185] [subscription-akka.actor.default-dispatcher-4] [akka://subscription/system] now supervising Actor[akka://subscription/system/log1-Slf4jLogger#731298157]
[DEBUG] [02/01/2017 10:26:13.201] [subscription-akka.actor.default-dispatcher-4] [akka://subscription/system] now watched by Actor[akka://subscription/]
[DEBUG] [02/01/2017 10:26:13.202] [webserver-akka.actor.default-dispatcher-11] [EventStream(akka://version)] Default Loggers started
[DEBUG] [02/01/2017 10:26:13.193] [version-akka.actor.default-dispatcher-2] [akka://version/system] now supervising Actor[akka://version/system/log1-Slf4jLogger#1075717908]
[DEBUG] [02/01/2017 10:26:13.206] [session-akka.actor.default-dispatcher-3] [akka://session/system/UnhandledMessageForwarder] started (akka.event.LoggingBus$$anonfun$startDefaultLoggers$2$$anon$3#1b5d5357)
[DEBUG] [02/01/2017 10:26:13.205] [webserver-akka.actor.default-dispatcher-13] [EventStream(akka://session)] Default Loggers started
[DEBUG] [02/01/2017 10:26:13.205] [webserver-akka.actor.default-dispatcher-8] [EventStream(akka://subscription)] Default Loggers started
[DEBUG] [02/01/2017 10:26:13.206] [subscription-akka.actor.default-dispatcher-4] [akka://subscription/system/UnhandledMessageForwarder] started (akka.event.LoggingBus$$anonfun$startDefaultLoggers$2$$anon$3#51839748)
[DEBUG] [02/01/2017 10:26:13.211] [subscription-akka.actor.default-dispatcher-2] [akka://subscription/system] now supervising Actor[akka://subscription/system/UnhandledMessageForwarder#2056207919]
serv http launch
[DEBUG] [02/01/2017 10:26:15.906] [webserver-akka.actor.default-dispatcher-8] [EventStream] shutting down: StandardOutLogger started
[DEBUG] [02/01/2017 10:26:15.909] [webserver-akka.actor.default-dispatcher-8] [EventStream] all default loggers stopped
[DEBUG] [02/01/2017 10:26:15.909] [webserver-akka.actor.default-dispatcher-3] [akka://webserver/system/log1-Slf4jLogger] stopped
[DEBUG] [02/01/2017 10:26:15.910] [webserver-akka.actor.default-dispatcher-7] [akka://webserver/system/IO-TCP] stopping
[DEBUG] [02/01/2017 10:26:15.910] [webserver-akka.actor.default-dispatcher-12] [akka://webserver/system/UnhandledMessageForwarder] stopped
[DEBUG] [02/01/2017 10:26:15.910] [webserver-akka.actor.default-dispatcher-16] [akka://webserver/system/IO-TCP/selectors] stopping
[DEBUG] [02/01/2017 10:26:15.910] [webserver-akka.actor.default-dispatcher-8] [akka://webserver/system] stopping
[DEBUG] [02/01/2017 10:26:15.910] [webserver-akka.actor.default-dispatcher-3] [akka://webserver/system/deadLetterListener] stopped
[DEBUG] [02/01/2017 10:26:15.910] [webserver-akka.actor.default-dispatcher-18] [akka://webserver/system/IO-TCP/selectors/$a] no longer watched by Actor[akka://webserver/system/IO-TCP/selectors#1324110335]
[DEBUG] [02/01/2017 10:26:15.910] [webserver-akka.actor.default-dispatcher-13] [akka://webserver/system/eventStreamUnsubscriber-1] stopped
[DEBUG] [02/01/2017 10:26:15.911] [webserver-akka.actor.default-dispatcher-18] [akka://webserver/system/IO-TCP/selectors/$a] stopped
[DEBUG] [02/01/2017 10:26:15.911] [webserver-akka.actor.default-dispatcher-13] [akka://webserver/system/IO-TCP/selectors] stopped
[DEBUG] [02/01/2017 10:26:15.912] [webserver-akka.actor.default-dispatcher-8] [akka://webserver/system/IO-TCP] stopped
[DEBUG] [02/01/2017 10:26:15.912] [webserver-akka.actor.default-dispatcher-13] [akka://webserver/system] stopped
[DEBUG] [02/01/2017 10:26:15.912] [webserver-akka.actor.default-dispatcher-18] [akka://webserver/] received AutoReceiveMessage Envelope(Terminated(Actor[akka://webserver/system]),Actor[akka://webserver/system])
[DEBUG] [02/01/2017 10:26:15.913] [webserver-akka.actor.default-dispatcher-18] [akka://webserver/] stopped
It seems I can't launch my app in background.
How can i do for launching it in background?
here is my Main.scala:
object WebServer extends App {
implicit val system = ActorSystem("webserver")
implicit val materializer = ActorMaterializer()
// needed for the future flatMap/onComplete in the end
implicit val executionContext = system.dispatcher
val ipServer = InetAddress.getLocalHost().getHostAddress()
val configApplication = ConfigFactory.load("application")
val serverFile = new File(args(0))
val configServer = ConfigFactory.parseFile(serverFile)
val routes =
new AppActiveRoute(system.actorOf(AppActiveHandler.props(), "AppActiveHandler")).route
val bindingFuture = Http().bindAndHandle(
routes,
ipServer,
configApplication.getInt("http.port")
)
println("serv http launch")
StdIn.readLine()
bindingFuture
.flatMap(_.unbind()) // trigger unbinding from the port
.onComplete(_ => {
cluster.close()
system.terminate()
})
bindingFuture.onFailure {
case ex: Exception =>
println(ex, "Failed to bind to {}:{}!", ipServer, configApplication.getInt("http.port"))
}

Answer 1

If your application is supposed to be dockerized and run in a container, you probably don't need this part
StdIn.readLine()
bindingFuture
.flatMap(_.unbind()) // trigger unbinding from the port
.onComplete(_ => {
cluster.close()
system.terminate()
})
Try deleting it.
If you care to gracefully shutdown your actor system when the VM exits, you can use a shutdown hook, as specified in this answer.