wso2 api manager modify JSON payload sent to backend

Question

I have REST API URL defined as

https://hostname/[version]/[service]/[operation]

and I would like to transform JSON payload in WSO2 API Manager in order to put version and operation inside.

So the WSO2 will send it to backend in the following form:

POST https://backend/[service]
{
    “version”: [version],
    “operation”: [operation]
}

So I need to put version and operation from URL to JSON payload. How to do it?

Answer 1

As I understand you want to create a new payload and POST with values from the resource URI definition (not API context).

Lets assume:

• you don't want to change the method (the resource is having POST method).
• the original request posted is JSON as well

You may want to create a (synapse) mediation flow as for ESB building such a message.

Plugging in the mediation is described in the documentation Adding Mediation Extensions . This mediation will be executed for every request of the API

Having resource https://hostname/[version]/[service]/[operation]

In the mediation, you may build the JSON payload

<payloadFactory media-type="json">
  <format>{
      "version":"$1", 
      "service": "$2", 
      "some_original_data": "$3"
    }</format>
  <args>
    <arg  expression="get-property('uri.var.version')"/>
    <arg  expression="get-property('uri.var.service')"/>
    <arg  expression="$.person.name" evaluator="json" />
  </args>
</payloadFactory>