Camel Apache: xpath to extract some value out of received XML

Question

during my Camel routes, I query a server (a HTTP GET) and as a result, I receive a 200 OK with a XML body looking similar like this:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<userProfiles xmlns="http://www.mycompany.com/AEContext/xmldata">
  <userProfile name="guest">
    <userProfileAttributes>
      <userProfileAttribute name="parameter1" value="data1" nameVisibility="ALL"/>  
      <userProfileAttribute name="parameter2" value="data2" nameVisibility="ALL"/>
      <userProfileAttribute name="parameter3" value="data3" nameVisibility="ALL"/>
    </userProfileAttributes>
  </userProfile>
</userProfiles>

Any idea how I would be able to get the value of "parameter2" in the XML part (in my example 'data2') and store that value in an exchange property ? I guess by using an xpath expression ? Or ... Thanks for your help.

Answer 1

An easy way to retrieve the value would be to use the XPath Language. It will allow you to extract the data you want and set it somewhere (header, body , ...). Here is how to set a parameter2 header with the value:

<setHeader headerName="parameter2">
  <xpath resultType="java.lang.String">
    /userProfiles/userProfile/userProfileAttributes/userProfileAttribute[2]/@value
  </xpath>
</setHeader>

Using Java DSL

An example using the Java DSL and setting the message body:

final Namespaces ns = new Namespaces("c", "http://www.mycompany.com/AEContext/xmldata");

// existing code
from(...)
  .setBody(
    ns.xpath(
      "/c:userProfiles/userProfile/userProfileAttributes/userProfileAttribute[2]/@value",   
      String.class)
   )
   .to(...);