Post object in Angular2 to Spring RestContoller using @RequestBody

Question

The connection between client and server works fine and the correct function addEpic is called on the server. The problem is, that just a new instance of Epic is created on the server, but the attributes from the client are not used. @RequestBody seems to be the problem. Shouldn't convert @RequestBody automatically from the json data to the specified class? Is the fundamental problem that Epic is a @Entity class?

It could also be that body is wrongly generated at the client. console.log(body) shows:

{"epic":{"id":"f97d885a-410f-fa6d-7adc-291e63d35341", "name":"OurName"}}

But my swagger-ui shows for body model shema:

{"id":"string", "name":"string"}

Client

  addEpic(epic:Epic):Observable<any> {
    let body = JSON.stringify({epic});
    let headers = new Headers({'Content-Type': 'application/json'});
    let options = new RequestOptions({headers: headers});

    return this.http.post(url + "addEpic", body, options)
      .map(this.extractHeader)
      .catch(this.handleError);
  }

export class Epic {
  id: string;
  name: string;
}

Server

    @RequestMapping(value="/addEpic", method = RequestMethod.POST)
    public ResponseEntity<Void> addEpic(@RequestBody Epic epic) {

        // Here it seems that constructor of epic is called and a new instance is created
        epicRepository.saveAndFlush(epic);

        return new ResponseEntity<Void>(HttpStatus.CREATED);
    }

@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Entity
public class Epic implements Serializable {
    private static final long serialVersionUID = -670305953055479441L;

    @Column
    private String id;

    @Column
    private String name
}

Answer 1

Your entity Epic has two properties 'id' and 'name'. In JSON :

{"id":"string", "name":"string"}

This is exactly what Swagger showed you.

So your client is doing it wrong, you should create the JSON there like

let body = JSON.stringify(epic);

Just remove the superflous {} around 'epic'.