[SOLVED] Spring how to create POST request with empty body?

Spring how to create POST request with empty body?

I'm trying to create a shopping Cart using Spring which will have cartId, product name, price. This will be done using a specific endpoint /api/carts. For this I would use the POST method and the @RequestBody but the requirement of my homework is to create a POST method with empty body. What is the logic around that? How do I do that in Spring?

My understanding is that I am also supposed to send data in the body like cartId, product name, price. What am I missing?

My code would be something like this

@RestController
@RequestMapping ("/api")
public class Controller {

  @Autowired
  CartService service;

  @PostMapping("/carts")
  ResponseEntity<CartDTO> createCart (@RequestBody CartDTO dto){
  Cart cart = new Cart(dto);
  etc

but the above will not have an empty body. Can someone explain the difference in post method with empty body and with a body? Thank you

Solution

It is technically impossible to post an empty body(aka no body)! You will always have a valid body for all requests based on http(see https://www.ietf.org/rfc/rfc2616.html#section-5)! The task, written in this terminology, is nonsense.

But you can post a valid body size of 0 bytes. That is the most matching interpretation of an "empty body". You can signalize a empty body if you neither post a Content-Length nor a Transfer-Encoding header. But thats not a non-body term. You always send a body, even if its 0 bytes long.