@Override
    protected String getServiceConfig(final String key, final Consumer<String> updateHandler, final Consumer<String> deleteHandler) {
        try {
            if (watchCache.containsKey(key)) {
                return null;
            }
            final Listener listener = new Listener() {
                @Override
                public Executor getExecutor() {
                    return null;
                }

                @Override
                public void receiveConfigInfo(final String configInfo) {
                    try {
                        if (StringUtils.isBlank(configInfo) && Objects.nonNull(deleteHandler)) {
                            deleteHandler.accept(key);
                        } else {
                            updateHandler.accept(configInfo);
                        }
                    } catch (Exception e) {
                        LOG.error("nacos sync listener receiveConfigInfo error", e);
                    }
                }
            };
            final String serviceConfig = configService.getConfigAndSignListener(key, NacosPathConstants.GROUP, 3000, listener);
            watchCache.put(key, listener);
            return serviceConfig;
        } catch (Exception e) {
            throw new ShenyuException(e);
        }
    }
Instantiates a new Nacos sync data service.

@param configService         the config service
@param pluginDataSubscriber the plugin data subscriber
@param metaDataSubscribers   the meta data subscribers
@param authDataSubscribers   the auth data subscribers
@param proxySelectorDataSubscribers the proxy selector data subscribers
@param discoveryUpstreamDataSubscribers the discovery upstream data subscribers
@param shenyuConfig          the shenyu config
shenyu-sync-data-center/shenyu-sync-data-nacos/src/main/java/org/apache/shenyu/sync/data/nacos/NacosSyncDataService.java