How to use is-xml-filter to validate SOAP request in Mule

Question

I have a main flow which is exposing a webservice :-

<flow name="ServiceFlow" doc:name="ServiceFlow">

<http:inbound-endpoint exchange-pattern="request-response" host="localhost" port="8082" path="mainData" doc:name="HTTP"/>

<cxf:jaxws-service  serviceClass="com.test.services.schema.maindata.v1.MainData"  doc:name="SOAP"/>

<component class="com.test.services.schema.maindata.v1.Impl.MainDataImpl" doc:name="JavaMain_ServiceImpl"/>

</flow>

Now I have another flow which is a proxy flow to this main flow :-

    <flow name="ProxyFlow" doc:name="ProxyFlow" processingStrategy="synchronous">

         <http:inbound-endpoint exchange-pattern="request-response"
                host="localhost" port="8086" path="proxy/mainData" doc:name="HTTP" />

        <!-- This is for SOAP Request validation -->
                  <message-filter  onUnaccepted="ValidationFailFlow" doc:name="filter to validate xml against xsd" throwOnUnaccepted="true" >
              <mulexml:is-xml-filter /> 
                </message-filter>
    <!-- ends -->

          <cxf:proxy-service  namespace="http://services.test.com/schema/MainData/V1" service="MainData"  payload="envelope" wsdlLocation="MainData.wsdl" doc:name="SOAP"/>

           <cxf:proxy-client payload="envelope" 
                doc:name="SOAP" />
            <http:outbound-endpoint exchange-pattern="request-response"
                host="localhost" port="8082" path="mainData" method="POST" doc:name="HTTP" />
        </flow>

<!-- This sub flow contains the message that need to be displayed in case of validation fails from validation filter -->   
<sub-flow name="ValidationFailFlow" doc:name="ValidationFailFlow">
        <logger message="SOAP Request is not valid!!" level="INFO" doc:name="Logger"/>
        <set-payload value="SOAP Request is not valid .... Message has been rejected by filter." doc:name="Set Payload"/>
    </sub-flow>
<!-- ends --> 

Now the issue is ... Since I have used a validation filter <mulexml:is-xml-filter /> in Proxy flow the webservice request is getting validated .. but in this case, a valid SOAP request is throwing exception... for example .. the following SOAP request is valid :-

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:v1="http://services.test.com/schema/MainData/V1">
   <soapenv:Header/>
   <soapenv:Body>
      <v1:insertDataRequest>
         <v1:Id>55</v1:Id>
         <v1:Name>ghghg</v1:Name>
         <v1:Age>666</v1:Age>
         <v1:Designation>hghghgh</v1:Designation>
      </v1:insertDataRequest>
   </soapenv:Body>
</soapenv:Envelope>

But it is throwing following exception :-

java.lang.RuntimeException: Couldn't parse stream.
    at org.apache.cxf.staxutils.StaxUtils.createXMLStreamReader(StaxUtils.java:1262)
    at org.apache.cxf.interceptor.StaxInInterceptor.handleMessage(StaxInInterceptor.java:105)
    at org.apache.cxf.phase.PhaseInterceptorChain.doIntercept(PhaseInterceptorChain.java:263)
    at org.apache.cxf.transport.ChainInitiationObserver.onMessage(ChainInitiationObserver.java:122)
    at org.mule.module.cxf.CxfInboundMessageProcessor.sendToDestination(CxfInboundMessageProcessor.java:338)
    at org.mule.module.cxf.CxfInboundMessageProcessor.process(CxfInboundMessageProcessor.java:144)
    at org.mule.module.cxf.config.FlowConfiguringMessageProcessor.process(FlowConfiguringMessageProcessor.java:48)
    at org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor.execute(ExceptionToMessagingExceptionExecutionInterceptor.java:24)
    at org.mule.execution.MessageProcessorNotificationExecutionInterceptor.execute(MessageProcessorNotificationExecutionInterceptor.java:58)
    at org.mule.execution.MessageProcessorExecutionTemplate.execute(MessageProcessorExecutionTemplate.java:44)

Caused by: com.ctc.wstx.exc.WstxIOException: Attempted read from closed stream.
    at com.ctc.wstx.stax.WstxInputFactory.doCreateSR(WstxInputFactory.java:536)
    at com.ctc.wstx.stax.WstxInputFactory.createSR(WstxInputFactory.java:585)
    at com.ctc.wstx.stax.WstxInputFactory.createSR(WstxInputFactory.java:610)
    at com.ctc.wstx.stax.WstxInputFactory.createXMLStreamReader(WstxInputFactory.java:316)
    at org.apache.cxf.staxutils.StaxUtils.createXMLStreamReader(StaxUtils.java:1260)
    ... 97 more
Caused by: java.io.IOException: Attempted read from closed stream.
    at org.apache.commons.httpclient.ContentLengthInputStream.read(ContentLengthInputStream.java:160)
    at com.ctc.wstx.io.BaseReader.readBytes(BaseReader.java:155)
    at com.ctc.wstx.io.UTF8Reader.loadMore(UTF8Reader.java:368)
    at com.ctc.wstx.io.UTF8Reader.read(UTF8Reader.java:111)
    at com.ctc.wstx.io.ReaderBootstrapper.initialLoad(ReaderBootstrapper.java:250)
    at com.ctc.wstx.io.ReaderBootstrapper.bootstrapInput(ReaderBootstrapper.java:133)
    at com.ctc.wstx.stax.WstxInputFactory.doCreateSR(WstxInputFactory.java:531)
    ... 101 more

And following SOAP response :-

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
   <soap:Body>
      <soap:Fault>
         <faultcode>soap:Server</faultcode>
         <faultstring>Couldn't parse stream.</faultstring>
      </soap:Fault>
   </soap:Body>
</soap:Envelope>

Please help ... How can I use <mulexml:is-xml-filter /> for validating SOAP request and what does the exception means for a valid SOAP request ???

Answer 1

The problem is that the filter consumes the stream thus the cxf proxy service do not have any data to work with.

Add a object to string transformer before the filter to load the request into memory. Then it can be reread by the cxf proxy service.

Something like this:

<http:inbound-endpoint exchange-pattern="request-response"
            host="localhost" port="8086" path="proxy/mainData" doc:name="HTTP" />

    <!-- Transform to String so we can reread the payload multiple times -->
    <object-to-string-transformer />
    <!-- This is for SOAP Request validation -->
    <message-filter  onUnaccepted="ValidationFailFlow" doc:name="filter to validate xml against xsd" throwOnUnaccepted="true" >
     <mulexml:is-xml-filter /> 
    </message-filter>
    <!-- ends -->