Angular 5 + Spring Boot post method doesn't work

Question

I use Angular 5 + Spring Boot. The problem is that I can not send information to my rest controller by post method. I do not get any error either from the client side or from the server side. Below the code you will see that I make get method which works correctly. Let me apologize for my Еnglish.

Spring Entity { Dish }

@Entity
@Table(name = "DISHES")
@Data
public class Dish implements Serializable {

    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "ID")
    private Long id;

    @Column(name = "NAME", unique = true)
    @NotNull(message = "Ястието трябва да има име.")
    @Size(min = 3, max = 30, message = "Името на ястието трябва да е между 3 и 30 символа.")
    private String name;

    @Column(name = "DESCRIPTION")
    @NotNull(message = "Описанието на ястието не може да е празно.")
    @Size(min = 3, max = 300, message = "Описанието на ястието трябва да е между 3 и 30 символа.")
    private String description;

    @JsonIgnore
    @OneToMany(cascade = CascadeType.ALL ,mappedBy = "dish")
    @JsonBackReference
    private List<DishCounter> dishCounters;
}

Angular Entity {Dish}

export class Dish {

    constructor(public id?: number, public name?: string, public description?: string) {

    }
}

Spring Rest Controller {Dish}

@CrossOrigin(origins = "http://localhost:4200")
@RestController
@RequestMapping("/dish")
public class DishRestController {

    private static final Logger logger = LoggerFactory.getLogger(DishRestController.class);

    private final DishService dishService;

    @Autowired
    public DishRestController(final DishService dishService) {
        this.dishService = dishService;
    }

    @GetMapping("/all")
    public ResponseEntity<List<Dish>> getAllDishes() {
        logger.info("Rest controller find all dishes");
        List<Dish> dishes = dishService.getAllDishes();

        return ResponseEntity.status(HttpStatus.OK).body(dishes);
    }

    @PostMapping("/save")
    public ResponseEntity<Void> saveDish(@RequestBody Dish dish) {
        dishService.saveDish(dish);
        return new ResponseEntity<>(HttpStatus.OK);
    }
}

And Angular post Method

 save(dish: Dish): Observable<Dish> {
        let result: Observable<Dish>;

        result = this.http.post(this.saveDishUrl, dish)
            .map((resp => {
                console.log(resp);
                return resp;
            }))
            .catch(e => {
                console.log(e);
                return Observable.throw(e);
            });

        console.log(result);

        return result;
    }

Answer 1

Where are you calling subscribe on the post function? I don't see it here. As http post returns an observable, you must subscribe to it to make the call.

http.post(....).subscribe(response => <DO SOMETHING WITH IT>);

Answer 2

This might not be all of the errors on your code but this is something I noticed.

Your Java @PostMapping doesn't specify what it should be expected to receive and what it should produce in return.

@PostMapping(value = "save", consumes = MediaType.APPLICATION_JSON_VALUE, 
    produces = MediaType.APPLICATION_JSON_VALUE)

For Angular 5, you're using Angular 4 service Syntax, I thought they changed that on 5.