Executing Groovy in WSO2 Script Mediator, Part 2 (XML)

In my earlier post, I wrote how to filter Json payload using Groovy scripts in WSO2 ESB script mediator. This post is its XML counterpart.

If you did not read my earlier post, the Script Mediator of WSO2 ESB used to invoke the functions of a variety of scripting languages such as JavaScript, Groovy, or Ruby.

In this example, payload consists of xml payload with the details of  set of employees. We are going to filter out
old employees (age >30) from this list. However using Groovy I found it easier to remove young employees and keep the old employees
in payload.

Prerequisites:
Download Groovy all dependency jar (I used groovy-all-2.2.0-beta-1.jar) into $ESB_HOME/repository/lib and start WSO2 ESB

Here is the payload before the script mediator.

<employees>
<employee>
<age>25</age>
<firstName>John</firstName>
<lastName>Doe</lastName>
</employee>
<employee>
<age>45</age>
<firstName>Anna</firstName>
<lastName>Smith</lastName>
</employee>
<employee>
<age>35</age>
<firstName>Peter</firstName>
<lastName>Jones</lastName>
</employee>
</employees>

 

Now lets write the script mediator which filter out employees younger than 30 years.

<property name="messageType"; value="application/json" scope="axis2" />
<property name="payload" expression="json-eval($.)" />
<script language="groovy">
import groovy.util.XmlSlurper;
import groovy.xml.MarkupBuilder;
import groovy.xml.StreamingMarkupBuilder;

def payload = mc.getPayloadXML();
def rootNode = new XmlSlurper().parseText(payload);
rootNode.children().findAll{it.age.text().toInteger() &lt; 30 }.replaceNode {};

mc.setPayloadXML(groovy.xml.XmlUtil.serialize(rootNode));
</script>

 

First I fetches payload using getPayloadXML provided by Synapse. Then I parse the payload as XML using parseText() of XmlSlurper class.
Then I findAll employees who’s age is less than 30 by finding and remove them. Finally serialize the object and set to synapse message context as new payload.
So the new payload consists of old employees as below

<employees>
<employee>
<age>45</age>
<firstName>Anna</firstName>
<lastName>Smith</lastName>
</employee>
<employee>
<age>35</age>
<firstName>Peter</firstName>
<lastName>Jones</lastName>
</employee>
</employees>