class Google::Auth::WebUserAuthorizer

def handle_auth_callback user_id, request
  callback_state, redirect_uri = WebUserAuthorizer.extract_callback_state(
    request
  )
  WebUserAuthorizer.validate_callback_state callback_state, request
  credentials = get_and_store_credentials_from_code(
    user_id:  user_id,
    code:     callback_state[AUTH_CODE_KEY],
    scope:    callback_state[SCOPE_KEY],
    base_url: request.url
  )
  [credentials, redirect_uri]
end