解析Spring Data JPA的Audit功能之审计数据库变更

<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
  <groupId>org.postgresql</groupId>
  <artifactId>postgresql</artifactId>
</dependency>
<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-security</artifactId>
</dependency>

spring.security.user.name=pkslow
spring.security.user.password=123456

@MappedSuperclass
@EntityListeners(AuditingEntityListener.class)
public class Auditable<U> {
    @CreatedBy
    @Column(name = "created_by")
    private U createdBy;

    @CreatedDate
    @Column(name = "created_date")
    private Date createdDate;

    @LastModifiedBy
    @Column(name = "last_modified_by")
    private U lastModifiedBy;

    @LastModifiedDate
    @Column(name = "last_modified_date")
    private Date lastModifiedDate;
  // getter
  //setter
}

@Entity
@Table(name = "pkslow_users")
public class User extends Auditable<String> {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long userId;
    private String name;
    private String email;
    private String country;
    private String website;
  //getter setter
}

@Configuration
@EnableJpaAuditing(auditorAwareRef = "auditorProvider")
public class JpaAuditingConfiguration {

    @Bean
    public AuditorAware<String> auditorProvider() {
        return () -> {
            String username = "system";
            SecurityContext context = SecurityContextHolder.getContext();
            if (context != null) {
                Authentication authentication = context.getAuthentication();
                if (authentication != null) {
                    username = authentication.getName();
                }
            }

            String result = username;
            return Optional.ofNullable(result);
        };
    }
}

@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    private UserRepository userRepository;
    @PostMapping
    public User save(@RequestBody User user) {
        return userRepository.save(user);
    }
}