如何在Camel-Scala中构建从文件到websocket客户端的路由？

Question

我需要读取/files目录下的文件，然后在websocket客户端上显示该文件的内容。这就是我在MyRouteBuilder.scala中所做的工作：

import org.apache.camel.component.websocket.WebsocketComponent
import org.apache.camel.{LoggingLevel, CamelContext, Exchange}
import org.apache.camel.scala.dsl.builder.ScalaRouteBuilder

/**
 * A Camel Router using the Scala DSL
 */
class MyRouteBuilder(override val context : CamelContext) extends ScalaRouteBuilder(context) {

  // an example of a Processor method
  val myProcessorMethod = (exchange: Exchange) => {
    exchange.getIn.setBody("block test")
  }

  val ws = context.getComponent("websocket", classOf[WebsocketComponent]);
  ws.setPort(8444);
  ws.setHost("127.0.0.1")
  // we can serve static resources from the classpath: or file: system
  ws.setStaticResources("classpath:.");

  "file://files?noop=true" ==> {
    setBody(convertBodyTo(classOf[String]))
    to("websocket://127.0.0.1:8444/")
  }
}

但是，当我运行它时，会给出以下stacktrace：

RouteId ProcessorId处理器运行时间(ms)[route1][route1][File://Files？noop=true][2][route1][convertBodyTo1][ConvertBodyTo[java.lang.String]][1][route1][SetBody[{org.apache.camel.scala.ScalaExpression@F736069}]][0][route1][to1][WebSocket://127.0.0.1:8444/][1]

Exchange[Id ID-vaisakh-ubuntu-45785-1455531433908-1-12 ExchangePattern InOnly标头{breadcrumbid=id-vaisakh-ubuntu-45785-1455531433908-1-11,CamelFileAbsolute=false,CamelFileAbsolutePath=/Home/Sagar/IDeaProjects/SampleIntegrationService/Files/paudies.json,CamelFileContentType=text/plain,CamelFileLastModified=1455526488000,

Answer 1

通过从标头设置connection key属性解决了此问题。

 from(websocketUrl) ==> {

     setProperty("wsConnKey", header("websocket.connectionkey"))
     to("file://files?noop=true")
 }

 "file://files?noop=true" ==> {

     setBody(convertBodyTo(classOf[String]))
     to(WEBSOCKET_RESPONSE_ENDPOINT)
 }

 from(WEBSOCKET_REPONSE_ENDPOINT) ==> {

     process(new Processor() {
         void process(Exchange exchange) {
             Object connectionKey = exchange.getproperty("wsConnKey");
             Object exchangeBody = exchange.getIn().getBody();
             exchange.getOut().setHeader("wsConnKey", connectionKey);
             exchange.getOut().setBody(exchangeBody);
         }
     })
    to(websocketUrl)
 }