您可以创建基于 actor 的源并通过已建立的 websocket 连接发送新消息.

You can create an actor based source and send new messages over the established websocket connection.

    val req = WebSocketRequest(uri = "ws://127.0.0.1/ws")
    val webSocketFlow = Http().webSocketClientFlow(req)

    val messageSource: Source[Message, ActorRef] = 
         Source.actorRef[TextMessage.Strict](bufferSize = 10, OverflowStrategy.fail)

    val messageSink: Sink[Message, NotUsed] =
        Flow[Message]
            .map(message => println(s"Received text message: [$message]"))
            .to(Sink.ignore)

    val ((ws, upgradeResponse), closed) =
        messageSource
            .viaMat(webSocketFlow)(Keep.both)
            .toMat(messageSink)(Keep.both)
            .run()

    val connected = upgradeResponse.flatMap { upgrade =>
        if (upgrade.response.status == StatusCodes.SwitchingProtocols) {
            Future.successful(Done)
        } else {
            throw new RuntimeException(s"Connection failed: ${upgrade.response.status}")
        }
    }

    ws ! TextMessage.Strict("Hello World")
    ws ! TextMessage.Strict("Hi")
    ws ! TextMessage.Strict("Yay!")

`