java - ManyToOne 双向关系中 POST 请求上的 org.hibernate.exception.ConstraintViolationException

Question

我尝试在 /addNewUser 端点上使用以下 POST 请求创建新用户:-

发布请求

{
    "username"   : "abc",
    "password"   : "123",
    "enabled"    : "true",
    "authorities": [{ 
                        "authority" : "ROLE_USER" 
                    }]
}

UserController 类:-

@PostMapping("/addNewUser")
    public UserModel addNewUser(@RequestBody UserModel user) {
        return userService.addNewUser(user);
    }

UserService 类:-

public UserModel addNewUser(UserModel user) {
        return userRepository.saveAndFlush(user);
    }

UserRepository接口(interface)

public interface UserRepository extends JpaRepository<UserModel, String> {

}

但我遇到以下异常:-

2020-04-30 21:14:00.441 ERROR 23653 --- [nio-8080-exec-7] o.h.engine.jdbc.spi.SqlExceptionHelper   : ERROR: null value in column "authority" violates not-null constraint
  Detail: Failing row contains (null, null).
2020-04-30 21:14:00.450 ERROR 23653 --- [nio-8080-exec-7] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.dao.DataIntegrityViolationException: could not execute statement; SQL [n/a]; constraint [authority]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement] with root cause

org.postgresql.util.PSQLException: ERROR: null value in column "authority" violates not-null constraint
  Detail: Failing row contains (null, null).

UserModel 类

@Entity
@Table(name = "users")
public class UserModel {
    @Id
    @Column(name = "username", unique = true, nullable = false)
    private String username;

    @Column(name = "password")
    private String password;

    @Column(name = "enabled")
    private boolean enabled;

    @OneToMany(mappedBy = "user", cascade = CascadeType.ALL)
    @JsonManagedReference
    private List<AuthoritiesModel> authorities;

    //getters and setters
}

AuthoritiesModel 类:-

@Entity
@Table(name = "authorities")
public class AuthoritiesModel implements Serializable {
    private static final long serialVersionUID = 1L;

    @Id
    @JsonBackReference
    @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinColumn(name="username", unique = false, nullable=false)
    private UserModel user;

    @Id
    @Column(name = "authority") 
    private String authority;

    //getters and setters
}

最初，我认为我的发布请求或 Jackson API 的反序列化存在一些问题，因此我打印了 Controller 方法中 UserModel 字段的值，并且所有值都已正确设置，包括 AuthoritiesModel。但是当我尝试保留 UserModel 对象时，它会抛出异常。

更新1:

如果我在没有权限的情况下发布请求，它不会抛出任何异常，但我得到的权限为 null 作为响应。

发布请求

{
    "username"   : "abc",
    "password"   : "123",
    "enabled"    : "true"
}

发布回复

{
    "username": "abc",
    "password": "123",
    "enabled": true,
    "authorities": null
}

Answer 1

反序列化请求正文时，AuthoritiesModel 上没有设置 UserModel。

你可以尝试这样的事情:

public UserModel addNewUser(UserModel user) {
    List<AuthorityModel> authorities = user.getAuthorities();
    authorities.stream().forEach(authority -> authority.setUser(user);
    return userRepository.saveAndFlush(user);
}