如何在camel-scala中建立从文件到websocket客户端的路由？

Question

我需要读取/files目录下的一个文件，然后在websocket客户端上显示该文件的内容。这就是我在MyRouteBuilder.scala中做的事情：

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/")
  }
}

然而，当我运行它时，它给出了以下堆栈跟踪：

堆栈跟踪

java.lang.IllegalArgumentException:无法向单个连接发送消息；未设置连接键。在org.apache.camel.component.websocket.WebsocketProducer.process(WebsocketProducer.java:57)在org.apache.camel.util.AsyncProcessorConverterHelper$ProcessorToAsyncProcessorBridge.process(AsyncProcessorConverterHelper.java:61)在org.apache.camel.processor.SendProcessor.process(SendProcessor.java:141)在org.apache.camel.management.InstrumentationProcessor.process(InstrumentationProcessor.java:77)在org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:460)在org.apache.camel.processor.CamelInternalProcessor.process(在org.apache.camel.processor.Pipeline.process(Pipeline.java:121) at org.apache.camel.processor.Pipeline.process(Pipeline.java:83) at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:190) at org.apache.camel.component.file.GenericFileConsumer.processExchange(GenericFileConsumer.java:442) at org.apache.camel.component.file.GenericFileConsumer.processBatch(GenericFileConsumer.java:214) at org)的CamelInternalProcessor.java:190)。apache.camel.component.file.GenericFileConsumer.poll(GenericFileConsumer.java:178) at org.apache.camel.impl.ScheduledPollConsumer.doRun(ScheduledPollConsumer.java:174) at org.apache.camel.impl.ScheduledPollConsumer.run(ScheduledPollConsumer.java:101) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180) atjava.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) el-2)线程#0 - file://files GenericFileOnCompletion WARN回滚文件策略: org.apache.camel.component.file.strategy.GenericFileRenameProcessStrategy@72611f35 java.lang.Thread.run Thread.java:745: GenericFileaudience.json DefaultErrorHandler发送失败错误(ExchangeId上的MessageId: ID-vaisakh-ubuntu-45785-1455531433908-1-11 : ID-vaisakh-ubuntu-45785-1455531433908-1-12)。尝试传递后耗尽:1捕获: java.lang.IllegalArgumentException:无法向单个连接发送消息；未设置连接键。

消息历史记录

file://files?noop=true route1 convertBodyTo[java.lang.String]中的RouteId ProcessorId Processor Elapsed (ms) route1 route1 convertBodyTo[java.lang.String]setBody[{org.apache.camel.scala.ScalaExpression@f736069}] route1 route1 websocket://127.0.0.1:8444/

交换

{breadcrumbId=ID-vaisakh-ubuntu-45785-1455531433908-1-11，，CamelFileAbsolutePath=/home/sagar/IdeaProjects/SampleIntegrationService/files/audience.json，CamelFileContentType= ExchangePattern / InOnly，CamelFileLastModified=1455526488000，CamelFileLength=150，CamelFileName=audience.json，CamelFileNameConsumed=audience.json，CamelFileNameOnly=audience.json，CamelFileParent=files，CamelFilePath= CamelFileAbsolute=false /InOnly，CamelFileRelativePath=audience.json，CamelRedelivered=false，com.mediaiqdigital.sampleIntegrationService.MyRouteBuilder@67a27caa)，CamelRedeliveryCounter=0} BodyType org.apache.camel.scala.dsl.SRouteDefinition Body SRouteDefinition(Route(route1)[[Fromfile://files?noop=true] BodyType[BodyType，com.mediaiqdigital.sampleIntegrationService.MyRouteBuilder@67a27caa)CamelRedeliveryCounter=0://127.0.0.1:8444/]]，BodyType org.apache.camel.scala.dsl.SRouteDefinition Body BodyType -> [ConvertBodyTojava.lang.String，87.0.0.1:8444/]]

Answer 1

已通过设置标头中的连接密钥属性解决此问题。

 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)
 }