@Transactional跟@DS动态数据源注解冲突的解决

目录

• @Transactional跟@DS动态数据源注解冲突
• 背景
• @Transactional执行流程
• 解决方法
• 动态数据源切换失败
• 由事务@Transactional注解导致动态数据源切换失效的问题

spring:
  datasource:
    dynamic:
      primary: A 
      datasource:
        A:
          url:..
          driver-class-name: com.mysql.jdbc.Driver
          username: root
          password:
        B:
          url: ..
          driver-class-name: com.mysql.jdbc.Driver
          username: root
          password:
        C:
          url: ..
          driver-class-name: com.mysql.jdbc.Driver
          username: root
          password:

@Mapper
@DS("A")
public interface AMapper{
      @Insert("insert into a ...")
      void save();
}

@Mapper
@DS("B")
public interface BMapper{
      @Insert("insert into b ...")
      void save();
}

@Mapper
@DS("C")
public interface CMapper{
      @Insert("insert into c ...")
      void save();
}

public class aService{ 
@Autowired
private aMapper、bMapper、cMapper
 
    @Transactional
    public void save(){
    aMapper.save();
    bMapper.save(); #报错
    cMapper.save();
    }    
}

public class DataSourceKey {
    /**
     * 用户数据源
     */
    public final static String USER = "userDataSource";
    /**
     * 报表数据源
     */
    public final static String REPORT = "reportDataSource";
    /**
     * 所有数据源的集合
     */
    final static List SOURCES = ImmutableList.of(USER, REPORT);
    /**
     * 根据包名找到数据源, 多数据源的前缀不能存在相同的。 例： user -> userDataSource
     *
     * @param pack 包名
     * @return 数据源名
     */
    public static String getDataSourceKey(String pack) {
        return SOURCES.stream().filter(s -> s.startsWith(pack)).findFirst().orElse(USER);
    }
}

@Component
@Aspect
@Order(-1)
@Slf4j
public class DynamicDataSourceAspect {
    @Pointcut("execution(* com.in.g.data.mapper..*.*(..))")
    public void dataSourcePointcut() {
    }
    @Before("dataSourcePointcut()")
    public void doBefore(JoinPoint point) throws Throwable {
        log.debug("切换数据源开始。。。。。。。。。。。。");
        Package pack = point.getSignature().getDeclaringType().getPackage();
        String str = StringUtils.substringAfterLast(pack.getName(), ".");
        String dataSourceKey = DataSourceKey.getDataSourceKey(str);
        DynamicDataSourceHolder.set(dataSourceKey);
        log.debug("切换数据源成功，当前数据源：{}", dataSourceKey);
    }
    @After("dataSourcePointcut()")
    public void doAfterReturning() throws Throwable {
        DynamicDataSourceHolder.clear();
    }
}

/**
 * 动态数据源持有者
 */
public class DynamicDataSourceHolder {
    public static ThreadLocal keyHolder = new ThreadLocal<>();
    public static void clear() {
        keyHolder.remove();
    }
    public static void set(String key) {
        keyHolder.set(key);
    }
    public static String get() {
        return keyHolder.get();
    }
}

/**
 * 动态数据源配置
 */
public class DynamicRoutingDataSource extends AbstractRoutingDataSource {
    @Override
    protected Object determineCurrentLookupKey() {
        return DynamicDataSourceHolder.get();
    }
}

//正确的代码   --这里偷懒了，直接controller调用dao层
@GetMapping("/testdb")
    public String testDateSources(){
　　　　 //缩小事务的范围
       add();
       rptFieldMapper.selectxxxx();
       
       return "sss";
    }
    @Transactional(rollbackFor = Exception.class)
    public void add() {
 　　　　userMapper.insertXXXX(xxxx);
 }

    //错误的代码，@Transactional注解会导致 数据源切换失败
    @GetMapping("/testdb")
    @Transactional(rollbackFor = Exception.class)
    public String testDateSources(){  
        userMapper.insertXXXX(xxxx);
        rptFieldMapper.selectXXXX();
        
        return "sss";
    }