@GetMapping("/parentTagId/{parentTagId}")
    public ShenyuAdminResult queryListByParentTagId(@PathVariable("parentTagId") @Valid final String parentTagId) {
        List<TagVO> tagVOList = Optional.ofNullable(tagService.findByParentTagId(parentTagId)).orElse(Lists.newArrayList());
        return ShenyuAdminResult.success(ShenyuResultMessage.DETAIL_SUCCESS, tagVOList);
    }
querylist by parentTagId.

@param parentTagId  parentTagId.
@return {@linkplain ShenyuAdminResult}
shenyu-admin/src/main/java/org/apache/shenyu/admin/controller/TagController.java