正确的RESTfull Web服务响应

Question

What should I return (JSON format) after GET, POST, PUT, DELETE requests?

I saw several variants. For example: 1) GET:

@RequestMapping(value = "/user/{id}", method = RequestMethod.GET,
        headers = "Accept=application/json")
public Shop getShopById(@PathVariable long id) {
    return mainService.getShopById(id);
}

2) GET:

@RequestMapping(value = "/user/{id}", method = RequestMethod.GET,
        headers = "Accept=application/json")
public ResponseEntity<Shop> getShopById(@PathVariable long id) {
    Shop shop = mainService.getShopById(id);

    if (shop == null) {
        return new ResponseEntity<Shop>(HttpStatus.NOT_FOUND);
    }
    return new ResponseEntity<Shop>(shop, HttpStatus.OK);
}

1) POST:

@RequestMapping(value="/users", method = RequestMethod.POST)
public User addShop(@RequestBody User user) {
    mainService.addShop(user);
    return user;enter code here
}

2) POST:

@RequestMapping(value="/users", method = RequestMethod.POST)
public User addShop(@RequestBody User user) {
    mainService.addShop(user);

    HttpHeaders headers = new HttpHeaders(); headers.setLocation(ucBuilder.path("/users").buildAndExpand(user.getId()).toUri());
    return new ResponseEntity<Void>(headers, HttpStatus.CREATED);
}

So what is the correct way to return the response? Should it be just an object as User or ResponseEntity ? The same question about PUT and DELETE methods.

Answer 1

您可能想看看HATEOAS 。

Answer 2

As far as I know, it depends on what HttpStatus (response code) you want to return. I always return ResponseEntity≤?> because it allows to specify HttpStatus, what is important for REST.

(you also should specify @ResponseBody and produces = MediaType.APPLICATION_JSON_VALUE)