spring return 视图模型或空主体的 CRUD DELETE 操作

Question

我想编写一个 DELETE 操作，return 如果不存在 id 错误，则为无内容正文。如果 id 不存在，我想重定向到对应的 GET 视图。

控制器代码：

@RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.GET)
public String getDeleteTodo(Model model, @PathVariable("id") String id)
{
    Optional<Todo> todo = todoRepository.findById(Long.decode(id));

    if (todo.isEmpty()) {
        model.addAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
        model.addAttribute("requestedId", id);
    }
    else {
        model.addAttribute("todo", todo.get());
    }

    return "v-todo-delete";
}

@RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.DELETE)
public String deleteTodo(@PathVariable String id, RedirectAttributes redirAttrs)
{
    boolean exists = todoRepository.existsById(Long.decode(id));

    if (exists) {
        todoRepository.deleteById(Long.decode(id));
        return ""; //here I want to return a no-content body response
    }
    else {
        redirAttrs.addFlashAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
        redirAttrs.addFlashAttribute("requestedId", id);

        return "redirect:/todo/delete" + id;
    }
}

有关视图的更多信息：

GET视图只是一个显示id对应的todo实体的视图。删除是通过使用 ajax 的按钮调用 DELETE 方法进行的。然后响应是 return 作为 204，正文中没有内容，我用 javascript 将用户重定向到主页...如果 DELETE 方法中不存在 id，我想重定向到显示错误消息的 GET 方法。

如果有人有想法这样做。提前致谢。

Answer 1

尝试使用 return 类型作为 ResponseEntity 以及任何响应正文和响应状态。请参考以下代码更改：

@RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.DELETE)
public ResponseEntity deleteTodo(@PathVariable String id, RedirectAttributes redirAttrs)
{
   boolean exists = todoRepository.existsById(Long.decode(id));

   if (exists) {
       todoRepository.deleteById(Long.decode(id));
       return new ResponseEntity(HttpStatus.NO_CONTENT); //This will return No Content status
   }
   else {
       redirAttrs.addFlashAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
       redirAttrs.addFlashAttribute("requestedId", id);

       return new ResponseEntity( "redirect:/todo/delete" + id, HttpStatus.OK);
   }
}

Answer 2

我的最终答案：

@RequestMapping(value = "/todo/delete/{id}", method = RequestMethod.DELETE)
public ResponseEntity<?> deleteTodo(@PathVariable String id, RedirectAttributes redirAttrs)
{
   boolean exists = todoRepository.existsById(Long.decode(id));

   if (exists) {
       todoRepository.deleteById(Long.decode(id));
       return new ResponseEntity<>(HttpStatus.NO_CONTENT);
   }
   else {
       redirAttrs.addFlashAttribute("msginfo", "ctl-todo.delete.msginfo.id-not-exist");
       redirAttrs.addFlashAttribute("requestedId", id);
       /* I use CONFLICT here to explain that the entity was possibly deleted
          by another user between the moment the user give the view containing
          the DELETE ajax link and the moment he click on it. */
       return new ResponseEntity<String>( "redirect:/todo/delete" + id, HttpStatus.CONFLICT);
   }
}

感谢 Mandar Dharurkar 和 Jeethesh Kotian 的帮助 ;)

spring return 视图模型或空主体的 CRUD DELETE 操作

spring CRUD DELETE action that return viewmodel or empty body

spring

spring-boot

spring-boot-2