JsonIdentityReference 规范化 JPA 实体的 OpenApi 模式答案

【问题标题】：OpenApi schema for JsonIdentityReference-normalized JPA EntitiesJsonIdentityReference 规范化 JPA 实体的 OpenApi 模式
【发布时间】：2021-12-06 02:06:51
【问题描述】：

使用@RestController、CrudRepository 和胶水@Services，我提供了对一些基于JPA 的对象的访问。

User 类引用List<Order>，而Order 引用User。

为了打破杰克逊无限递归循环，我通过@JsonIdentityReference(alwaysAsId=true) 替换嵌套对象。但是，springdoc 似乎忽略了它，并且仍然生成指向 Order 而不是例如的 OpenApi Spec Long（id 类）。

如何告诉 springdoc 将 User.orders 映射到 List<Long> 或（甚至更好）映射到 List<OrderId>？


@RestController
public class UsersController {

    @ApiResponses(value = {
        @ApiResponse(responseCode = "200", description = "successful operation", content = @Content(array = @ArraySchema(schema = @Schema(implementation = User.class))))
    })
    @GetMapping("/")
    public ResponseEntity<Iterable<User>> listUsers() {
        return ResponseEntity.ok(users.findAll());
    }

    // getters and setters omitted

}

@Entity
@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
public class User {

    @Schema(description = "The id of the user", required = true)
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @OneToMany(mappedBy = "order")
    @JsonIdentityReference(alwaysAsId=true)
    private List<Order> orders = Collections.emptyList();

    // getters and setters omitted
}


@Entity
@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
public class Order {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id", nullable = false)
    @Schema(required = true)
    private Long id;

    @ManyToOne
    @JoinColumn(name = "user_id")
    @JsonIdentityReference(alwaysAsId=true)
    private User user;

    @OneToMany(mappedBy = "order")
    @JsonIdentityReference(alwaysAsId=true)
    private List<Product> products = Collections.emptyList();

    // getters and setters omitted

}

【问题讨论】：

标签： spring-boot spring-data-jpa jackson openapi springdoc

【解决方案1】：

简单的解决方案（破坏语义）：将@ArraySchema 添加到这样的定义中：

    @OneToMany(mappedBy = "order")
    @JsonIdentityReference(alwaysAsId=true)
    @ArraySchema(schema = @Schema(implementation = Long.class))
    private List<Order> orders = Collections.emptyList();

【讨论】：