Clojurians Log v2

I'm trying to write a POST route with Compojure. I'm not sure how to get the body of what it sends to my functions --- I'm getting nulls that I don't expect. It's probably something fairly obvious: https://github.com/mathpunk/certainty-derivative/blob/rest-server/src/certainty_derivative/server.clj#L55

I figured, this would just give me what the content was back.... instead I get {:status 200, :headers {"Content-Type" "application/json; charset=utf-8"}, :body "{\"description\":\"Success! Probably!\",\"record\":null}"}

Hi, I want to provide a link for xls downloading. how to provide a stream that represent a file for download in ring response?