class ActionDispatch::ActionableExceptions

def redirect_to(location)
  uri = URI.parse location
  if uri.relative? || uri.scheme == "http" || uri.scheme == "https"
    body = ""
  else
    return [400, { Rack::CONTENT_TYPE => "text/plain; charset=utf-8" }, ["Invalid redirection URI"]]
  end
  [302, {
    Rack::CONTENT_TYPE => "text/html; charset=#{Response.default_charset}",
    Rack::CONTENT_LENGTH => body.bytesize.to_s,
    ActionDispatch::Constants::LOCATION => location,
  }, [body]]
end