How to make an additional http call inside api and process response? - wso2

Question

I'm trying to create Message Mediation Policies, with which I can make an additional http call, process the response and enrich the current message. How can i do this? I use call Mediator, but I don’t understand how to handle the response.
<?xml version="1.0" encoding="UTF-8"?> <sequence name="call_out_handler" trace="disable" xmlns="http://ws.apache.org/ns/synapse">
<call blocking="true">
<endpoint>
<http method="get" uri-template="http://192.168.99.100:8888/stubFORAPIMan/ServletWithTimeout"/>
</endpoint>
</call> </sequence>

Answer 1

You can use the PayloadFactory Mediator [1] to handle/format the response you received by calling an endpoint inside the Call mediator.
An example would be like this. Say you want to provide a json object by populating the values from the response you received; you can define the json object format in the "format" section and populate the values by providing the arguments in the "args" section in the PayloadFactory mediator as below.
<payloadFactory media-type="json">
<format>
{
"Data": {
"PaymentSubmissionId": "$1",
"PaymentId": "$2",
"Status": "$3",
"CreationDateTime": "$4"
}
}
</format>
<args>
<arg evaluator="xml" expression="$body//PaymentSubId"/>
<arg evaluator="xml" expression="$body//PaymentId"/>
<arg evaluator="xml" value="AcceptedSettlementInProcess"/>
<arg value="2019-06-05T15:15:22+00:00"/>
</args>
</payloadFactory>
<property name="messageType" value="application/json" scope="axis2" type="STRING"/>
[1] https://docs.wso2.com/display/EI640/PayloadFactory+Mediator