docker akka和scala，应用程序无故启动和停止

Question

我使用 Akka 创建了一个 scala 应用程序。

当我使用 scala /Statistics.jar ./server.conf 运行它时，它运行良好。 但是如果我把它放在服务器中或者如果我把它放在一个 docker 映像中，当我启动它时，应用程序会启动然后直接停止。

这是我的日志：

    ...
    [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

我似乎无法在后台启动我的应用程序。 如何在后台启动它？

这是我的 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

如果您的应用程序应该被 docker 化并在容器中运行，您可能不需要这部分

    StdIn.readLine()
    bindingFuture
        .flatMap(_.unbind()) // trigger unbinding from the port
        .onComplete(_ => {
        cluster.close()
        system.terminate()
    })

尝试删除它。

如果您希望在 VM 退出时正常关闭您的 Actor 系统，您可以使用关闭挂钩，如 this answer 中指定的那样。