Spark.getData() on a callback "REQUEST_HEADERS" field is empty. It should have the request data from the server calling the callback.

It doesn't have Request URL, Content-Type, Content-Length or any other request headers.

Would love this feature

Thanks

I want to verify what server is requesting the callback page.

So I can choose to allow or deny it.

The extra header info would be very useful in verifying it as well. 

Important data from xsolla is sent in the headers as well.

I'm running into this issue as well; is there any progress on this? I need to verify an OAuth token coming from an Authorization header, and I can't obtain it.