Play Framework -手动升级到Web socket

Question

升级到web socket是在play frame中抽象出来的。如何手动实现？

我使用play框架创建了一个web socket应用程序。我可以在web socket客户端和服务器(我创建的)之间建立连接，但是升级到web socket已经被play-framework抽象出来了。

def chatSystem(): WebSocket = WebSocket.acceptOrResult[String, String] { request =>
    Future.successful{
      AuthenticationService.doBasicAuthentication(request.headers) match {
        case Results.Ok => Right(ActorFlow.actorRef { out => ChatServiceActor.props(out) })
        case _ => Left(Unauthorized)
      }
    }
  }

URL : ws://localhost:9000/chatSystem/test123

在建立连接之前，我需要做以下事情：

如果WebSocket服务器不能识别URL路径中的userId，它应该发送一个状态为404的超文本传输协议响应并中止WebSocket连接

如果WebSocket服务器不同意使用客户端提供的某个子协议，它必须使用不带Sec-WebSocket-Protocol报头的响应完成WebSocket握手，然后立即关闭WebSocket连接。

我不确定如何手动实现逻辑，以便向客户端发送升级响应，然后建立web套接字连接。

Answer 1

可悲的是，我认为这是不可能的，我能够检测到WebSocket是一个Handler，而play期望实现路由的方法返回一个Handler，所以，从理论上讲，如果你可以构建一个返回Handler的方法，该方法是一个将RequestHeader转换为另一个Handler (如trait CustomHandler extends (RequestHeader => Handler) with Handler)的函数，那么，你就可以创建一个实例来检查是否应该建立web套接字连接。

但是，如果你这样做，你会在触发请求时得到一个异常，希望有一个我遗漏的关键细节，我建议在他们的github上打开一个工单：

我的堆栈跟踪是：

akka.http.impl.util.One2OneBidiFlow$OutputTruncationException: Inner flow was completed without producing result elements for 1 outstanding elements
    at akka.http.impl.util.One2OneBidiFlow$OutputTruncationException$.apply(One2OneBidiFlow.scala:22)
    at akka.http.impl.util.One2OneBidiFlow$OutputTruncationException$.apply(One2OneBidiFlow.scala:22)
    at akka.http.impl.util.One2OneBidiFlow$One2OneBidi$$anon$1$$anon$4.onUpstreamFinish(One2OneBidiFlow.scala:97)
    at akka.stream.impl.fusing.GraphInterpreter.processEvent(GraphInterpreter.scala:504)
    at akka.stream.impl.fusing.GraphInterpreter.execute(GraphInterpreter.scala:378)
    at akka.stream.impl.fusing.GraphInterpreterShell.runBatch(ActorGraphInterpreter.scala:588)
    at akka.stream.impl.fusing.GraphInterpreterShell$AsyncInput.execute(ActorGraphInterpreter.scala:472)
    at akka.stream.impl.fusing.GraphInterpreterShell.processEvent(ActorGraphInterpreter.scala:563)
    at akka.stream.impl.fusing.ActorGraphInterpreter.akka$stream$impl$fusing$ActorGraphInterpreter$$processEvent(ActorGraphInterpreter.scala:745)
    at akka.stream.impl.fusing.ActorGraphInterpreter$$anonfun$receive$1.applyOrElse(ActorGraphInterpreter.scala:760)
    at akka.actor.Actor.aroundReceive(Actor.scala:517)
    at akka.actor.Actor.aroundReceive$(Actor.scala:515)
    at akka.stream.impl.fusing.ActorGraphInterpreter.aroundReceive(ActorGraphInterpreter.scala:670)
    at akka.actor.ActorCell.receiveMessage(ActorCell.scala:588)
    at akka.actor.ActorCell.invoke(ActorCell.scala:557)
    at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:258)
    at akka.dispatch.Mailbox.run(Mailbox.scala:225)
    at akka.dispatch.Mailbox.exec(Mailbox.scala:235)
    at akka.dispatch.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
    at akka.dispatch.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
    at akka.dispatch.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
    at akka.dispatch.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
akka.http.impl.util.One2OneBidiFlow$OutputTruncationException: Inner flow was completed without producing result elements for 1 outstanding elements
    at akka.http.impl.util.One2OneBidiFlow$OutputTruncationException$.apply(One2OneBidiFlow.scala:22)
    at akka.http.impl.util.One2OneBidiFlow$OutputTruncationException$.apply(One2OneBidiFlow.scala:22)
    at akka.http.impl.util.One2OneBidiFlow$One2OneBidi$$anon$1$$anon$4.onUpstreamFinish(One2OneBidiFlow.scala:97)
    at akka.stream.impl.fusing.GraphInterpreter.processEvent(GraphInterpreter.scala:504)
    at akka.stream.impl.fusing.GraphInterpreter.execute(GraphInterpreter.scala:378)
    at akka.stream.impl.fusing.GraphInterpreterShell.runBatch(ActorGraphInterpreter.scala:588)
    at akka.stream.impl.fusing.GraphInterpreterShell$AsyncInput.execute(ActorGraphInterpreter.scala:472)
    at akka.stream.impl.fusing.GraphInterpreterShell.processEvent(ActorGraphInterpreter.scala:563)
    at akka.stream.impl.fusing.ActorGraphInterpreter.akka$stream$impl$fusing$ActorGraphInterpreter$$processEvent(ActorGraphInterpreter.scala:745)
    at akka.stream.impl.fusing.ActorGraphInterpreter$$anonfun$receive$1.applyOrElse(ActorGraphInterpreter.scala:760)