WSO2 ESB 4.9 - 发送调解器导致错误

Question

过去几天我一直在处理一个资源（我对 WSO2 还很陌生，所以我还是很慢），当我通过 SoapUI 向它提交请求时，它会记录所有应该达到的内容<send/> 调解器，然后转储以下错误：

ERROR -  Failed to submit the response {org.apache.synapse.transport.passthru.PassThroughHttpSender}
java.lang.NullPointerException
	at org.apache.synapse.transport.passthru.util.SourceResponseFactory.create(SourceResponseFactory.java:64)
	at org.apache.synapse.transport.passthru.PassThroughHttpSender.submitResponse(PassThroughHttpSender.java:462)
	at org.apache.synapse.transport.passthru.PassThroughHttpSender.invoke(PassThroughHttpSender.java:267)
	at org.apache.axis2.engine.AxisEngine.send(AxisEngine.java:442)
	at org.apache.synapse.core.axis2.Axis2Sender.sendBack(Axis2Sender.java:212)
	at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.send(Axis2SynapseEnvironment.java:444)
	at org.apache.synapse.mediators.builtin.SendMediator.mediate(SendMediator.java:102)
	at org.apache.synapse.mediators.AbstractListMediator.mediate(AbstractListMediator.java:81)
	at org.apache.synapse.mediators.base.SequenceMediator.mediate(SequenceMediator.java:277)
	at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.mediateFromContinuationStateStack(Axis2SynapseEnvironment.java:679)
	at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.injectMessage(Axis2SynapseEnvironment.java:244)
	at org.apache.synapse.core.axis2.SynapseCallbackReceiver.handleMessage(SynapseCallbackReceiver.java:529)
	at org.apache.synapse.core.axis2.SynapseCallbackReceiver.receive(SynapseCallbackReceiver.java:172)
	at org.apache.axis2.engine.AxisEngine.receive(AxisEngine.java:180)
	at org.apache.synapse.transport.passthru.ClientWorker.run(ClientWorker.java:247)
	at org.apache.axis2.transport.base.threads.NativeWorkerPool$1.run(NativeWorkerPool.java:172)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)

[2015-12-10 13:11:00,508] ERROR -  Access-Control-Allow-Credentials:true,Cache-Control:no-cache,Content-Type:application/json,Etag:W/"2-mZFLkyvTelC5g8XnyQrpOw",Expires:-1,Pragma:no-cache,Vary:Origin, X-HTTP-Method-Override,Via:1.1 vegur,X-Content-Type-Options:nosniff,X-Powered-By:Express,<?xml version='1.0' encoding='utf-8'?><soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"><soapenv:Body><jsonObject><TYPE></TYPE><NODE></NODE><STATUS>200 [OK]</STATUS></jsonObject></soapenv:Body></soapenv:Envelope> Unexpected error sending message back {org.apache.synapse.core.axis2.Axis2Sender}
org.apache.axis2.AxisFault: Failed to submit the response
	at org.apache.synapse.transport.passthru.PassThroughHttpSender.handleException(PassThroughHttpSender.java:610)
	at org.apache.synapse.transport.passthru.PassThroughHttpSender.invoke(PassThroughHttpSender.java:269)
	at org.apache.axis2.engine.AxisEngine.send(AxisEngine.java:442)
	at org.apache.synapse.core.axis2.Axis2Sender.sendBack(Axis2Sender.java:212)
	at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.send(Axis2SynapseEnvironment.java:444)
	at org.apache.synapse.mediators.builtin.SendMediator.mediate(SendMediator.java:102)
	at org.apache.synapse.mediators.AbstractListMediator.mediate(AbstractListMediator.java:81)
	at org.apache.synapse.mediators.base.SequenceMediator.mediate(SequenceMediator.java:277)
	at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.mediateFromContinuationStateStack(Axis2SynapseEnvironment.java:679)
	at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.injectMessage(Axis2SynapseEnvironment.java:244)
	at org.apache.synapse.core.axis2.SynapseCallbackReceiver.handleMessage(SynapseCallbackReceiver.java:529)
	at org.apache.synapse.core.axis2.SynapseCallbackReceiver.receive(SynapseCallbackReceiver.java:172)
	at org.apache.axis2.engine.AxisEngine.receive(AxisEngine.java:180)
	at org.apache.synapse.transport.passthru.ClientWorker.run(ClientWorker.java:247)
	at org.apache.axis2.transport.base.threads.NativeWorkerPool$1.run(NativeWorkerPool.java:172)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
	at org.apache.synapse.transport.passthru.util.SourceResponseFactory.create(SourceResponseFactory.java:64)
	at org.apache.synapse.transport.passthru.PassThroughHttpSender.submitResponse(PassThroughHttpSender.java:462)
	at org.apache.synapse.transport.passthru.PassThroughHttpSender.invoke(PassThroughHttpSender.java:267)
	... 16 more

资源接受来自 SoapUI 的 JSON 提交，如下所示：

{"tests":[{"type":"DSS","node":"2"}]}

从该提交中，它得出要测试的系统类型 (DSS) 以及该系统上要测试的节点 (2)。在这种情况下，它运行以下序列，以便在我们正在运行的 DSS 上测试节点 2：

<sequence name="dss_node_2_seq" trace="disable" xmlns="http://ws.apache.org/ns/synapse">
  <log level="custom">
    <property name="[[ SQNC ]]" value="STARTING DSS2 SEQUENCE"/>
  </log>
  <call>
    <endpoint key="dss_node_2"/>
  </call>
</sequence>

这个序列显然会调用 dss_node_2 端点，该端点此时指向一个带有一些模板化有效 JSON 的典型代码页面：

<endpoint name="dss_node_2" xmlns="http://ws.apache.org/ns/synapse">
  <http method="post" trace="disable" uri-template="http://jsonplaceholder.typicode.com/posts/1"/>
</endpoint>

我已将资源放入Kobra.io page，以便您查看并进行必要的更改。我目前仅在 DSS 上对其进行测试，但有几种类型是可能的，每种类型都有一定数量的节点。

如果有人能建议为什么它会向我抛出这些错误以及如何解决它，那将非常有帮助并且非常感谢，因为我已经坚持了几个小时并且变得非常沮丧！

Answer 1

尝试使用 send Mediator 而不是 call mediator ，它会等待整个流程完成，send 可以帮助您立即发送响应。

 <send>
<endpoint key="dss_node_2"/>
</send>  

Answer 2

尝试在发送中介之前移动这部分（在您的 API 中用于向调用者发送响应）（它不能在调用中介之前定义）：

<property name="messageType" scope="axis2" type="STRING" value="application/json"/>
      <header action="remove" name="To" scope="default"/>
      <property name="RESPONSE" scope="default" type="STRING" value="true"/>
      <property action="remove" name="NO_ENTITY_BODY" scope="axis2"/>

Answer 3

尝试使用响应中介， 代替

此外，验证有效负载以包含在发送之前写入的正确标头。您可以使用