private void fetchResources() {
        getResourceFetcher()
            .exceptionHandler(exceptionHandler)
            .fetch(data -> {
                rawData = data;
                processData();
                if (apiResultHandler != null)
                    apiResultHandler.handle(apis);
                if (clientResultHandler != null)
                    clientResultHandler.handle(clients);
            });
    }
Excepute the fetcher and load the resources.
gateway/engine/vertx-polling/src/main/java/io/apiman/gateway/engine/vertx/polling/PolicyConfigLoader.java