@GetMapping("/{id}")
    public ShenyuAdminResult detailApi(@PathVariable("id")
                                       @Existed(message = "api is not existed",
                                               provider = ApiMapper.class) final String id) {
        ApiVO apiVO = apiService.findById(id);
        return ShenyuAdminResult.success(ShenyuResultMessage.DETAIL_SUCCESS, apiVO);
    }
detail plugin.

@param id plugin id.
@return {@linkplain ShenyuAdminResult}
shenyu-admin/src/main/java/org/apache/shenyu/admin/controller/ApiController.java