<properties>
    <java.version>11</java.version>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <spring-boot.version>2.6.13</spring-boot.version>
</properties>
<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jdbc</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-aop</artifactId>
    </dependency>
    <dependency>
        <groupId>com.mysql</groupId>
        <artifactId>mysql-connector-j</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid-spring-boot-starter</artifactId>
        <version>1.2.16</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>
<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-dependencies</artifactId>
            <version>${spring-boot.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

DROP TABLE IF EXISTS `tb_user`;
CREATE TABLE `tb_user` (
  `id` bigint NOT NULL AUTO_INCREMENT,
  `username` varchar(50) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
BEGIN;
INSERT INTO `tb_user` (`id`, `username`) VALUES (1, '張三');
INSERT INTO `tb_user` (`id`, `username`) VALUES (2, '李四');
INSERT INTO `tb_user` (`id`, `username`) VALUES (3, '王五');
COMMIT;
SET FOREIGN_KEY_CHECKS = 1;

DROP TABLE IF EXISTS `tb_user`;
CREATE TABLE `tb_user` (
  `id` int NOT NULL AUTO_INCREMENT,
  `username` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
BEGIN;
INSERT INTO `tb_user` (`id`, `username`) VALUES (1, 'Vker');
INSERT INTO `tb_user` (`id`, `username`) VALUES (2, 'Jack');
INSERT INTO `tb_user` (`id`, `username`) VALUES (3, 'Lucy');
COMMIT;
SET FOREIGN_KEY_CHECKS = 1;

spring:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    druid:
      master:
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://127.0.0.1:3306/db_dynamic1?serverTimezone=UTC&useUnicode=true&characterEncoding=UTF8&useSSL=false
        username: root
        password: root_root
      slave:
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://127.0.0.1:3306/db_dynamic2?serverTimezone=UTC&useUnicode=true&characterEncoding=UTF8&useSSL=false
        username: root
        password: root_root
      initial-size: 1
      min-idle: 1
      max-active: 20
      test-on-borrow: true

@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface DataSources {
    String value() default "master";
}

@Component
@Primary
public class DynamicDataSources extends AbstractRoutingDataSource {
    public static ThreadLocal<String> name = new ThreadLocal<>();
    @Resource
    DataSource master;
    @Resource
    DataSource slave;
    @Override
    protected Object determineCurrentLookupKey() {
        return name.get();
    }
    @Override
    public void afterPropertiesSet() {
        Map<Object, Object> ds = new HashMap<>();
        ds.put("master", master);
        ds.put("slave", slave);
        super.setTargetDataSources(ds);
        super.setDefaultTargetDataSource(master);
        super.afterPropertiesSet();
    }
}

@Component
@Aspect
public class DynamicDataSourcesAspect {
    Logger logger = LoggerFactory.getLogger(DynamicDataSourcesAspect.class);
    @Before("@annotation(dataSources)")
    public void before(DataSources dataSources) {
        String value = dataSources.value();
        DynamicDataSources.name.set(value);
        logger.info("進(jìn)入AOP代理: {}", value);
    }
}

@Configuration
public class DynamicDataSourcesConfig {
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.druid.master")
    public DataSource master() {
        return DruidDataSourceBuilder.create().build();
    }
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.druid.slave")
    public DataSource slave() {
        return DruidDataSourceBuilder.create().build();
    }
    @Bean
    public DataSourceTransactionManager dataSourceTransactionManager1(@Qualifier("master") DataSource master) {
        DataSourceTransactionManager dataSourceTransactionManager =
                new DataSourceTransactionManager();
        dataSourceTransactionManager.setDataSource(master);
        return dataSourceTransactionManager;
    }
    @Bean
    public DataSourceTransactionManager dataSourceTransactionManager2(@Qualifier("slave") DataSource slave) {
        DataSourceTransactionManager dataSourceTransactionManager =
                new DataSourceTransactionManager();
        dataSourceTransactionManager.setDataSource(slave);
        return dataSourceTransactionManager;
    }
}

public class User {
    private Long id;
    private String username;
   // 省略了 getter setter
}

public interface UserMapper {
    List<User> selectAllUser();
}

@Repository
public class UserMapperImpl implements UserMapper {
    @Resource
    private JdbcTemplate jdbcTemplate;
    @Override
    public List<User> selectAllUser() {
        String sql = "select * from tb_user";
        return jdbcTemplate.query(sql,
                new BeanPropertyRowMapper<>(User.class));
    }
}

public interface UserService {
    List<User> list();
}

@Service
public class UserServiceImpl implements UserService {
    @Resource
    private UserMapper userMapper;
    @Override
    public List<User> list() {
        return userMapper.selectAllUser();
    }
}

@RestController
public class UserController {
    @Resource
    private UserService userService;
    @GetMapping("list1")
    public List<User> list1() {
        return userService.list();
    }
    @GetMapping("list2")
    @DataSources("slave")
    public List<User> lis2t() {
        return userService.list();
    }
}

@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class})
public class DynamicDatasourceDemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(DynamicDatasourceDemoApplication.class, args);
    }
}