response.mainpart is null

[styganesh]

I am trying to send the response back to requester using Return Template Response to Requestor Assertion and returning ${response.mainpart} but it is empty as shown in service debugger window as "mainpart = null" but in fact the backend is sending a response as shown in the postman(left side of the screenshot).

I am able to get the response when i directly use Route via HTTP Assertion without using Return Template Response to Requestor Assertion

 

Is this because of the Content-Type "application/vnd.kafka.binary.v1+json" ? Is there an extra configuration on Gateway which needs to be done to support this MIME Type ?

 

 

 

This is similar to Mysterious empty response message raised by Nicolas_Afonso , haunting me now even with correctly set Content-Type header

 

I have already tried setting io.httpDefaultContentType cluster wide property to application/vnd.kafka.binary.v1+json without any success in getting the backend response.

 

FYI Gateway version used is : 8.3

 

Regards,

Ganesh Reddy

[bloan03]

Since its a multipart message you need to use  ${response.parts[0]}

maybe .mainpart at the end. Let me know if this works for you. Been a while since I dealt with multipart messages in the gateway.

[styganesh]

Thanks bloan03

Indeed it solved by using ${response.parts[0]} but how do i differentiate for a normal response to a multipart?

[bloan03]

The answer is in the question. If the response is a MIME type then you use ${response.parts}. If the response is just a normal body message then you can just use ${response.mainpart}.

 

Message Layer Context Variables - CA API Gateway - 9.0 - CA Technologies Documentation

[Nicolas.Afonso]

Hi Ganesh,

 

My problem was different : the server did not send me Content-Type along its responses !

In such case, the gateway did not know how to handle them ...

 

If you're dealing with a kafka rest api, try to enforce application/json content type by adding a "Accept: application/json" header. Is it possible that Gateway does not support this MIME type.