class HTTP::Client

def make_request_body(opts, headers)
  case
  when opts.body
    opts.body
  when opts.form
    form = make_form_data(opts.form)
    headers[Headers::CONTENT_TYPE] ||= form.content_type
    form
  when opts.json
    body = MimeType[:json].encode opts.json
    headers[Headers::CONTENT_TYPE] ||= "application/json; charset=#{body.encoding.name.downcase}"
    body
  end
end