订单系统中的数据一致性方案及RocketMQ事务消息详解

/**
 * 发送事务消息
 *
 * @param topic   topic
 * @param message 消息对象
 */
public void sendMessageInTransaction(String topic, Object message) {
    String transactionId = UUID.randomUUID().toString();
    TransactionSendResult result = this.rocketMQTemplate.sendMessageInTransaction(topic, MessageBuilder.withPayload(message)
            .setHeader(RocketMQHeaders.TRANSACTION_ID, transactionId)
            .build(), message);
}

@RocketMQTransactionListener
public class OrderTransactionListener implements RocketMQLocalTransactionListener {

    /**
     * 执行本地事务，即处理核心链路
     * @param msg
     * @param arg
     * @return
     */
    @Override
    public RocketMQLocalTransactionState executeLocalTransaction(Message msg, Object arg) {
        try {
          	// 事务transactionId
            String transactionId = msg.getHeaders().get("rocketmq_TRANSACTION_ID").toString();
            // 本地事务，执行核心链路业务
            String payload = new String((byte[]) msg.getPayload());
            OrderTranscationMesageDTO data = JSONObject.parseObject(payload, OrderTranscationMesageDTO.class);
            orderService.executeCoreBusiness(data.getPayMoney(),data.getOrderDO(), data.getTransactionNo(),data.getPayType(),transactionId);
        } catch (Exception e) {
            log.error("本地事务执行异常:{}事务消息回滚", e.getMessage());
            return RocketMQLocalTransactionState.ROLLBACK;
        }
      	log.info("提交事务消息");
        return RocketMQLocalTransactionState.COMMIT;
    }

    /**
     * 校验本地事务（broker未收到提交或回滚事务消息时主动回查）
     * @param msg
     * @return
     */
    @Override
    public RocketMQLocalTransactionState checkLocalTransaction(Message msg) {
        // 事务transactionId
        String transactionId = msg.getHeaders().get("rocketmq_TRANSACTION_ID").toString();
        // 数据库能查到，说明本地事务执行失败，需要回滚
        if (Objects.isNull(transcationLogDao.getById(transactionId))){
            return RocketMQLocalTransactionState.ROLLBACK;
        }
        return RocketMQLocalTransactionState.COMMIT;
    }

}

/**
  * 核心业务，并记录RocketMQ事务ID
*/
@GlobalTransactional  // seata全局事务
public void executeCoreBusiness(BigDecimal payMoney, AppDerivativeGoodsOrderDO orderDO, String transactionNo, String payType,String transactionId) {
		// 核心业务伪代码
    orderService.execute();
    storeFeign.execute();
    scoreFeign.execute();
    
    // 数据库记录rocket事务消息ID 用于异常情况下的回查
    if (Objects.nonNull(transactionId)){
        //写入事务日志
        TransactionLogDO log = new TransactionLogDO();
        log.setId(transactionId);
        log.setBusiness("order");
        log.setForeignKey(String.valueOf(orderDO.getId()));
        transcationLogDao.save(log);
    }
}

CREATE TABLE `transaction_log` (
  `id` varchar(32) COLLATE utf8mb4_bin NOT NULL DEFAULT '' COMMENT '事务ID',
  `business` varchar(32) COLLATE utf8mb4_bin NOT NULL COMMENT '业务标识',
  `foreign_key` varchar(32) COLLATE utf8mb4_bin NOT NULL COMMENT '对应业务表中的主键',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin;

@RocketMQMessageListener(topic = "order_topic",consumerGroup = "order_group")
public class TestListener implements RocketMQListener<MessageExt> {
    @Override
    public void onMessage(MessageExt messageExt) {
        if(messageExt.getReconsumeTimes() >= 3){
            log.error("消息重试已达最大次数，将通知业务人员排查问题。{}",messageExt.getMsgId());
            //消息处理，第3次处理失败后，发送邮件通知人工介入
            sendMail(messageExt.getMsgId());
        }
        // 仓储物流相关业务 
        wmsService.execute(messageExt.getBody());
    }
}