WSO2ESB Parallel SOAP calls - wso2

Question

I have the following problem:
Develop a WSDL Based Proxy that calls several different SOAP Web services in parallel and returns the responses:
<inSequence>
<log level="full"/>
<iterate xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:agg="http://www.test.ro/aggregate"
preservePayload="true"
attachPath="//soapenv:Body"
expression="//agg:AggregateRequest/agg:messageRequest">
<target>
<sequence>
<property name="messageId"
expression="//soapenv:Body/agg:messageRequest/agg:messageId[node()]"/>
<property name="endpoint"
expression="//soapenv:Body/agg:messageRequest/agg:endpoint[node()]"/>
<xslt key="CleanPayload" source="/"/>
<send>
<endpoint key="MirrorEndpoint"/>
</send>
</sequence>
</target>
</iterate>
</inSequence>
<outSequence>
<property name="resp" scope="default">
<agg:AggregateResponse xmlns:agg="http://www.test.ro/aggregate"/>
</property>
<aggregate>
<completeCondition timeout="10">
<messageCount min="-1" max="-1"/>
</completeCondition>
<onComplete xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
expression="$body/*"
enclosingElementProperty="resp">
<log level="full"/>
<send/>
</onComplete>
</aggregate>
</outSequence>
My challenges are:
how do I pass the messageId from inSequence to outSequence so I can match the response to the request (similar to local environment from Message Broker)
how do I set the endpoint key with the text from agg:endpoint
I know this may be a newbie question but I'm having a hard time finding good tutorials on this topic.
Thank you

Answer 1

When you set a property (scope default) inside the In Sequence, you can find back it's value inside the Out Sequence.
Set this property inside your In Sequence :
<property name="IN_MESSAGE_ID" expression="get-property('MessageID')"/>
you can use get-property('IN_MESSAGE_ID') in your Out Sequence
If you want to send a message to a dynamic address, you can set "To" header and use send mediator :
<header name="To" expression="get-property('MY_DESTINATION')"/>
<send/>

Answer 2

Try setting the messageId as a HTTP header property,
<header name="MessageId" value="0001" scope="transport"/>
And retrieve this header in the outSequence
<property name="MessageId" expression="get-property('MessageId')"/>
I havnt tested this out, so give a feedback on whether it works