@PostMapping("/register-metadata")
    @ResponseBody
    public String registerMetadata(@RequestBody final MetaDataRegisterDTO metaDataRegisterDTO) {
        if (Objects.isNull(metaDataRegisterDTO.getNamespaceId())) {
            metaDataRegisterDTO.setNamespaceId(Constants.SYS_DEFAULT_NAMESPACE_ID);
        }
        publisher.publish(metaDataRegisterDTO);
        return ShenyuResultMessage.SUCCESS;
    }
Register metadata string.

@param metaDataRegisterDTO the meta data register dto
@return the string
shenyu-admin/src/main/java/org/apache/shenyu/admin/controller/ShenyuClientHttpRegistryController.java