protected function _handleLoginAction(ServerRequest $request, Response $response)
    {
        $request->allowMethod($this->getConfig('requestMethod'));

        $providerName = $request->getParam('provider');
        $provider = $this->_getService($request)->getProvider($providerName);
        $authUrl = $provider->makeAuthUrl();

        $this->_setRedirectUrl($request);

        return $response->withLocation($authUrl);
    }