Spring Boot - 管理事务和多个数据源

使用多个数据源管理事务是许多企业级应用程序中常见的需求。Spring Boot提供了一种简便的方式来实现这一目标。本文将介绍如何使用Spring Boot来管理事务并处理多个数据源的情况，并提供相关的案例代码。

xml
    org.springframework.boot
    spring-boot-starter-data-jpa
    org.springframework.boot
    spring-boot-starter-jdbc
    org.springframework.boot
    spring-boot-starter-web
    org.springframework.boot
    spring-boot-starter-transaction

properties
# 第一个数据源
spring.datasource.url=jdbc:mysql://localhost:3306/db1
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
# 第二个数据源
spring.datasource.second.url=jdbc:mysql://localhost:3306/db2
spring.datasource.second.username=root
spring.datasource.second.password=123456
spring.datasource.second.driver-class-name=com.mysql.jdbc.Driver

java
@Entity
@Table(name = "users")
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    // 省略其他属性和方法
}
public interface UserRepository extends JpaRepository {
}
@Entity
@Table(name = "products")
public class Product {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    // 省略其他属性和方法
}
public interface ProductRepository extends JpaRepository {
}

java
@Service
public class UserService {
    @Autowired
    private UserRepository userRepository;
    @Transactional(transactionManager = "transactionManager")
    public void saveUser(User user) {
        userRepository.save(user);
    }
}
@Service
public class ProductService {
    @Autowired
    private ProductRepository productRepository;
    @Transactional(transactionManager = "secondTransactionManager")
    public void saveProduct(Product product) {
        productRepository.save(product);
    }
}

java
@Configuration
@EnableTransactionManagement
public class TransactionConfig {
    @Autowired
    private EntityManagerFactory entityManagerFactory;
    @Autowired
    private DataSource dataSource;
    @Bean(name = "transactionManager")
    public PlatformTransactionManager transactionManager() {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(entityManagerFactory);
        transactionManager.setDataSource(dataSource);
        return transactionManager;
    }
    @Bean(name = "secondTransactionManager")
    public PlatformTransactionManager secondTransactionManager() {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(entityManagerFactory);
        transactionManager.setDataSource(dataSource2);
        return transactionManager;
    }
}

java
@RestController
public class UserController {
    @Autowired
    private UserService userService;
    @PostMapping("/users")
    public ResponseEntity createUser(@RequestBody User user) {
        userService.saveUser(user);
        return ResponseEntity.ok("User created successfully");
    }
}
@RestController
public class ProductController {
    @Autowired
    private ProductService productService;
    @PostMapping("/products")
    public ResponseEntity createProduct(@RequestBody Product product) {
        productService.saveProduct(product);
        return ResponseEntity.ok("Product created successfully");
    }
}