Question

I am designing a Proxy Service sequence that includes an XQuery transformation. I have a problem with referencing the registry file containing the transformation.

Here is the sequence:

<sequence name="MySequence" xmlns="http://ws.apache.org/ns/synapse" >
  <xquery key="conf:/wsdl/xqueryRequest.xq"
          target="..."
          xmlns:ns="http://org.apache.synapse/xsd"  >
     <variable xmlns:ns2="http://..." name="var1" expression="..." type="ELEMENT" />
  </xquery>
  <send>
     <endpoint>...</endpoint>
  </send>
</sequence>

The file containing the XQuery transformation is uploaded in

/_system/config/wsdl/xqueryRequest.xq

And this is the exception I am getting:

WARN ERROR_DETAIL : org.apache.synapse.SynapseException: 
Unable to execute the query at 
org.apache.synapse.mediators.xquery.XQueryMediator.handleException(XQueryMediator.java:627) at
org.apache.synapse.mediators.xquery.XQueryMediator.mediate(XQueryMediator.java:130) at
org.apache.synapse.mediators.AbstractListMediator.mediate(AbstractListMediator.java:60) at
...
Caused by: java.lang.NullPointerException at
org.wso2.carbon.mediation.registry.WSO2Registry.lookup(WSO2Registry.java:177) at 
org.apache.synapse.registry.AbstractRegistry.getResource(AbstractRegistry.java:63) at
org.apache.synapse.config.SynapseConfiguration.getEntry(SynapseConfiguration.java:693) at
org.apache.synapse.core.axis2.Axis2MessageContext.getEntry(Axis2MessageContext.java:194) at
org.apache.synapse.mediators.xquery.XQueryMediator.performQuery(XQueryMediator.java:233) at 
org.apache.synapse.mediators.xquery.XQueryMediator.mediate(XQueryMediator.java:123) 
... 11 more 

The exception shows a NullPointer at WSO2Registry.lookup so I assume that the problem is in finding the XQuery file in the registry, this part:

key="conf:/wsdl/xqueryRequest.xq"

The documentation shows two code snippets(390 and 391) with XQuery transformation but non of them explains howto reference the XQuery file.

Question: What should be the correct value for the key parameter? Do I need to use the “Local Entry” feature? If yes, then should I define the value as “Inline XML Entry” or “Inline Text”?

UPDATE 03/23/12:

Question 2: Perhaps a simpler question: Where should I copy/upload the xqueryRequest.xq file when I set Xquery mediator’s key field to key=”xqueryRequest.xq”?

Answer 1

Can you try saving your xquery as a local entry and refer it from the XQuery mediator.
(Please have a look at local entry samples)