Is it possible to change producer in server depending on client request parameter?

Problem statement

I'd like for my API to be able to be able to respond in both json and xml, for that I need to change producer depending on a query parameter contents. I can't find how to do it, is it possible? If so, could I ask for some guidance what should I look at? Producer is set by the WriteResponse function, but how do I pass a producer to this function (from handler scope)

Swagger specification

anything where

produces:
- application/json
- application/xml

Environment

swagger version: dev go version: 1.9.2 OS: n/a