docs: public static void start(FsSettings settings, ElasticsearchClient esClient) {
          // We create the service only one
          if (httpServer == null) {
              // create a resource config that scans for JAX-RS resources and providers
              // in fr.pilato.elasticsearch.crawler.fs.rest package
              final ResourceConfig rc = new ResourceConfig()
                      .registerInstances(
                              new ServerStatusApi(esClient, settings),
                              new UploadApi(settings, esClient))
                      .register(MultiPartFeature.class)
                      .register(RestJsonProvider.class)
                      .register(JacksonFeature.class)
                      .register(new CORSFilter(settings.getRest()))
                      .packages("fr.pilato.elasticsearch.crawler.fs.rest");
  
              // create and start a new instance of grizzly http server
              // exposing the Jersey application at BASE_URI
              httpServer = GrizzlyHttpServerFactory.createHttpServer(URI.create(settings.getRest().getUrl()), rc);
              logger.info("FS crawler Rest service started on [{}]", settings.getRest().getUrl());
          }
      }