class Bullet::Rack

def set_header(headers, header_name, header_array)
  # Many proxy applications such as Nginx and AWS ELB limit
  # the size a header to 8KB, so truncate the list of reports to
  # be under that limit
  header_array.pop while header_array.to_json.length > 8 * 1024
  headers[header_name] = header_array.to_json
end