conn() :: %Plug.Conn{
  adapter: term(),
  assigns: term(),
  before_send: term(),
  body_params: term(),
  cookies: term(),
  halted: term(),
  host: term(),
  method: term(),
  owner: term(),
  params: term(),
  path_info: term(),
  path_params: term(),
  port: term(),
  private: term(),
  query_params: term(),
  query_string: term(),
  remote_ip: term(),
  req_cookies: term(),
  req_headers: term(),
  request_path: term(),
  resp_body: term(),
  resp_cookies: term(),
  resp_headers: term(),
  scheme: term(),
  script_name: term(),
  secret_key_base: term(),
  state: term(),
  status: term()
}

reason() :: :permission_denied | :invalid_auth_header | any()