WSO2 - ESB | FOREACH MEDIATOR

FOREACH MEDIATOR

In the previous note, we saw how we can use custom classes as Mediators.

Moving on to cover other important mediation techniques, I was going through online documentation for 'FOREACH MEDIATOR' using this link -

https://docs.wso2.com/display/ESB490/Sample+18%3A+Transforming+a+Message+Using+ForEach+Mediator

when I realized, the sample code provided can be made more illustrative and a bit easier.

So code buddies, here we go with our version to create a small demo, using foreach mediator.

1. Kicking off with a sequence generation -

Declaring 'main2' as our sequence to imbibe foreach mediator -

xml version -

<?xml version="1.0" encoding="UTF-8"?>

<sequence name="main2" trace="enable" xmlns="http://ws.apache.org/ns/synapse">

<in>

<foreach expression="//m0:getQuote/m0:request"

xmlns:m0="http://services.samples"

xmlns:ns="http://org.apache.synapse/xsd" xmlns:ns3="http://org.apache.synapse/xsd">

<sequence>

<payloadFactory media-type="xml">

<format>

<m0:checkPriceRequest>

<m0:code>$1</m0:code>

</m0:checkPriceRequest>

</format>

<args>

<arg evaluator="xml" expression="//m0:request/m0:symbol"/>

</args>

</payloadFactory>

</sequence>

</foreach>

<log level="full"/>

</in>

<out/>

</sequence>

2. Defining an API to use the above sequence -

Let's call it 'foreachAPI' -

XML version -

<api xmlns="http://ws.apache.org/ns/synapse" name="foreachAPI" context="/fe">

<resource methods="POST GET" inSequence="main2" outSequence="main2"/>

</api>

3. Let's also enable the debug logging, for the above API -

4. Time to hit the API.

Let's use the same XML provided in the tutorial i.e. stockQuoteReq.xml -

<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope"
xmlns:m0="http://services.samples"
xmlns:xsd="http://services.samples/xsd">
    <soap:Header/>
    <soap:Body>
        <m0:getQuote>
            <m0:request><m0:symbol>IBM</m0:symbol></m0:request>
            <m0:request><m0:symbol>WSO2</m0:symbol></m0:request>
            <m0:request><m0:symbol>MSFT</m0:symbol></m0:request>
        </m0:getQuote>
    </soap:Body>
</soap:Envelope>

Save it locally, and invade the directory where it is parked. Run the below curl command -

curl -d @stockQuoteReq.xml -H "Content-Type: application/soap+xml;charset=UTF-8" "http://172.16.2.34:8280/fe/foreachAPI"

5. Output obtained, all the things done using console, no need to deploy any code 😃

o/p xml -

<?xml version="1.0" encoding="UTF-8"?>

<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope" xmlns:m0="http://services.samples" xmlns:xsd="http://services.samples/xsd">

<soap:Body>

<m0:getQuote>

<m0:checkPriceRequest>

<m0:code>IBM</m0:code>

</m0:checkPriceRequest>

<m0:checkPriceRequest>

<m0:code>WSO2</m0:code>

</m0:checkPriceRequest>

<m0:checkPriceRequest>

<m0:code>MSFT</m0:code>

</m0:checkPriceRequest>

</m0:getQuote>

</soap:Body>

</soap:Envelope>

Keep experimenting buddies, share your thoughts!