code: public function createService(ServiceLocatorInterface $serviceLocator)
      {
          $options = $serviceLocator->get('HtSettingsModule\Options\ModuleOptions');
          $settingsService = new SettingsService(
              $options,
              $serviceLocator->get('HtSettingsModule_SettingsMapper'),
              $serviceLocator->get('HtSettingsModule\Service\NamespaceHydratorProvider')
          );
          if ($options->getCacheOptions()->isEnabled()) {
              $settingsService->setCacheManager($serviceLocator->get('HtSettingsModule\Service\CacheManager'));
          }
  
          return $settingsService;
      }
docs: Gets settings service
  
  @param  ServiceLocatorInterface $serviceLocator
  @return SettingsService