I’m trying a GET request that uses hateoas RepresentationModelAssembler in Spring Boot project with this method:

    @GetMapping("/{postId}")
    public EntityModel<Post> one(@PathVariable Long postId) {
        Post post = postRepository.findById(postId)
                .orElseThrow(() -> new CustomExceptionHandling.ResourceNotFoundException("Post", "ID", postId));
        return assembler.toModel(post);
    }

and this is my assembler

    @Component
    public static class PostModelAssembler implements RepresentationModelAssembler<Post, EntityModel<Post>> {
        @Override
        public @NonNull EntityModel<Post> toModel(@NonNull Post post) {
            return EntityModel.of(post,
                    linkTo(methodOn(PostController.class).one(post.getId())).withSelfRel()
            );
        }
    }

this is Post.java:

@Entity(name = "post")
@Data
@AllArgsConstructor
@NoArgsConstructor
@Builder
public class Post {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(name = "created_at")
    @Builder.Default
    private LocalDateTime createdAt = LocalDateTime.now();
    private String caption;

    @ManyToOne
    @JoinColumn(name = "user_id")
    private User user;
}

Received Response:
{
“createdAt”: “2023-01-01T12:00:00”,
“caption”: “Caption 1”,
“_links”: {
“self”: {
“href”: “http://localhost:8080/posts/1”
}
}
}

Expected Response:
a similar one that includes user and id.

NOTE: I tried using @JsonInclude(JsonInclude.Include.ALWAYS and Include.NOT_NULL), @JsonProperty, @JsonIgnoreProperties({"hibernateLazyInitializer", "handler"}), removed lombok and added public getters and setters, made id fields public, but nothing worked
EXTRA NOTE: when I added @JsonIdentityInfo( generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
it produced the error: “Type definition error: [simple type, class com.example.demo.model.Post]” and somewhere below it: “Invalid Object Id definition for com.example.demo.model.Post: cannot find property with name ‘id’ (through reference chain: org.springframework.hateoas.EntityModel[“content”])”