public GetResponse getRange(final String key, final GetOption getOption) {
        try {
            return this.client.getKVClient().get(bytesOf(key), getOption).get();
        } catch (ExecutionException | InterruptedException e) {
            LOG.error("etcd getRange key {} error", key, e);
            throw new ShenyuException(e);
        }
    }
get keyResponse.
@param key watch key.
@param getOption get option.
@return key response.
shenyu-registry/shenyu-registry-etcd/src/main/java/org/apache/shenyu/registry/etcd/EtcdClient.java