code: public static function getAdldapProvider() {
          if(static::getExtensionOptions('adldap-providername') != '__USE_DEFAULT_PROVIDER__') {
              $provider = Yii::$app->ad->getProvider(static::getExtensionOptions('adldap-providername'));
          } else {
              $provider = Yii::$app->ad->getDefaultProvider();
          }
  
          return $provider;        
      }
docs: Get the Adldap2 provider name from the extension options.
  See constant variable EXTENSION_OPTIONS_DEFAULT at the top of the class