Spring：无法持久化用@JsonIgnore注释的实体

Question

我是Spring靴的初学者，不能解决问题。我有一个实体类（Customer）和一个REST存储库（CustomerRepository）。类包含一些我不想被REST存储库公开的敏感字段。因此，我使用@jsonIgnore注释对这些字段进行了注释，如下所示：

package br.univali.sapi.entities;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.InheritanceType;

import com.fasterxml.jackson.annotation.JsonIgnore;

@Entity
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
public class Customer
{
    @Id
    @GeneratedValue
    private Long id = null;

    private String login;

    private String name;

    @JsonIgnore
    private String password;

    @JsonIgnore
    private String email;

    public Customer()
    {

    }

    public Long getId()
    {
            return id;
    }

    public void setId(Long id)
    {
            this.id = id;
    }

    public String getLogin()
    {
            return login;
    }

    public void setLogin(String login)
    {
            this.login = login;
    }

    public String getName()
    {
            return name;
    }

    public void setName(String name)
    {
            this.name = name;
    }

    public String getPassword()
    {
            return password;
    }

    public void setPassword(String password)
    {
            this.password = password;
    }

    public String getEmail()
    {
            return email;
    }

    public void setEmail(String email)
    {
            this.email = email;
    }
}

一切正常，我的REST API返回了所需的结果。但是，当我向API发出POST请求以插入新实体时，我会收到数据库错误:“Column password Can't be Null”、“Column email Can't be Null”。

在POST请求中，密码和电子邮件与其他参数一起发送到服务器，但似乎被忽略了。如果删除@JSONIGNORE注释，实体将正常持久化。

我知道我可以用投影来隐藏这些区域。但投影是URL中的可选参数。这样，经验丰富的用户就可以从请求URL中删除参数，并查看这些字段。

如果我可以隐式地强制一个投影，那就解决了问题，但这似乎仅仅使用Spring框架是不可能做到的。我可以使用Apache URL重写来实现这一点，但维护会很糟糕。

有没有人知道我该怎么解决这个问题？谢谢！

public interface CustomerViewDTO
{
    public Long getId();
    public String getLogin();
    public String getName();
}

public class CustomerUpdateDTO
{
   private String login;
   private String name;
   private String password;
   private String email;

   // Getters and Setters ommited for breviety
}

@Transactional(readOnly = true)
public interface CustomerRepository extends JPARepository<Customer, Long>
{
   // Using derived query
   public CustomerViewDTO findByIdAsDTO(Long id);

   // Using @Query annotation
   @Query("SELECT C FROM Customer C WHERE C.id = :customerId")
   public CustomerViewDTO findByIdAsDTO(@Param("customerId") Long id);
}   

@RestController
public class CustomerController
{
    @Autowired
    private CustomerService customerService;

    @RequestMapping(method = "PATCH", path = "/customers/{customerId}")
    public ResponseEntity<?> updateCustomer(@PathVariable Long customerId, @RequestBody CustomerUpdateDTO customerDTO)
    {
        CustomerViewDTO updatedCustomer = customerService.updateCustomer(customerId, customerDTO);

        return ResponseEntity.ok(updatedCustomer);
    }

    @RequestMapping(method = GET, path = "/customers/{customerId}")
    public ResponseEntity<?> findCustomerById(@PathVariable Long customerId)
    {
        return ResponseEntity.ok(customerService.findByIdAsDTO(Long));
    }
}

@Service
public class CustomerService
{
    @Autowired
    private CustomerRepository customerRepository;

    // Follow this tutorial:
    // https://www.baeldung.com/entity-to-and-from-dto-for-a-java-spring-application
    @Autowired
    private ModelMapper modelMapper; 

    @Transactional(readOnly = false)
    public CustomerViewDTO updateCustomer(Long customerId, CustomerUpdateDTO customerDTO)
    {
         Customer customerEntity = customerRepository.findById(customerId);

         // This copies all values from the DTO to the entity
         modelMapper.map(customerDTO, customerEntity); 

         // Now we have two aproaches: 
         // 1. save the entity and convert back to DTO manually using the model mapper
         // 2. save the entity and call the repository method which will convert to the DTO automatically
         // The second approach is the one I use for several reasons that
         // I won't explain here

         // Here we use save and flush to force JPA to execute the update query. This way, when we do the select the entity will come with the fields updated
         customerEntity = customerRepository.saveAndFlush(customerEntity);

         // First aproach
         return modelMapper.map(customerEntity, CustomerViewDTO.class);

         // Second approach
         return customerRepository.findByIdAsDTO(customerId);
    }

    @Transactional(readOnly = true)
    public CustomerViewDTO findByIdAsDTO(Long customerId)
    {
         return customerRepository.findByIdAsDTO(customerId);
    }
}

Answer 1

我想您在db级别上没有null约束。基本上，当您在字段上执行@jsonignore时，您只是没有传递它，数据库就不能插入该值，这是非常清楚的。

所以我在这里看到的解决方案是这样的：

1）删除@jsonIgnore注释，以便能够执行POST请求。