浅析RocketMQ

SpringBoot引入RocketMQ

快速构建单机RocketMQ

https://www.haveyb.com/article/3079 参考这篇文章，快速构建单机RocketMQ

项目引入jar包和配置

        <dependency>
            <groupId>org.apache.rocketmq</groupId>
            <artifactId>rocketmq-spring-boot-starter</artifactId>
            <version>2.3.1</version>
        </dependency>

rocketmq:
  consumer:
    group: oneCoupon_merchant_admin_consumer_group
    # 一次拉取消息最大值，注意是拉取消息的最大值而非消费最大值
    pull-batch-size: 10
  name-server: xxx:9876
  producer:
    # 发送同一类消息的设置为同一个group，保证唯一
    group: oneCoupon_merchant_admin_producer_group
    # 发送消息超时时间，默认3000
    sendMessageTimeout: 10000
    # 发送消息失败重试次数，默认2
    retryTimesWhenSendFailed: 2
    # 异步消息重试此处，默认2
    retryTimesWhenSendAsyncFailed: 2
    # 消息最大长度，默认1024 * 1024 * 4(默认4M)
    maxMessageSize: 4096
    # 压缩消息阈值，默认4k(1024 * 4)
    compressMessageBodyThreshold: 4096
    # 是否在内部发送失败时重试另一个broker，默认false
    retryNextServer: false

在console中添加消费者

示例

生产者

@Component
@RequiredArgsConstructor
@Slf4j
public class ShortLinkStatsSaveProducer {

    @Resource
    private RocketMQTemplate rocketMQTemplate;

    public void send(String topic ,Map<String, String> producerMap) {
        log.info("send message to rocketMQ, topic: {}, producerMap: {}", topic, producerMap);
        rocketMQTemplate.syncSend(topic, producerMap);
    }
}

消费者

@Component
@RocketMQMessageListener(consumerGroup = "saaslink_consumer_group", topic = RedisKeyConstant.SHORT_LINK_STATS_STREAM_TOPIC_KEY)
@Slf4j
public class ShortLinkStatsSaveConsumer implements RocketMQListener<MessageExt> {
@Override
    public void onMessage(MessageExt msgExt) {
        String msgId = msgExt.getMsgId();
        // 使用redis实现幂等
        if (messageQueueIdempotentHandler.isMessageBeingConsumed(msgId.toString())) {
            // 判断当前的这个消息流程是否执行完成
            if (messageQueueIdempotentHandler.isAccomplish(msgId.toString())) {
                return;
            }
            throw new ServiceException("消息未完成流程，需要消息队列重试");
        }
        try {
            byte[] msgExtBody = msgExt.getBody();
            // 转为map
            Map<String, String> producerMap = JSON.parseObject(msgExtBody, Map.class);
            ShortLinkStatsRecordDTO statsRecord = JSON.parseObject(producerMap.get("statsRecord"), ShortLinkStatsRecordDTO.class);
            // 实际新增的逻辑
            actualSaveShortLinkStats(producerMap.get("fullShortUrl"), producerMap.get("gid"), statsRecord);
        } catch (Throwable ex) {
            // 某某某情况宕机了
            messageQueueIdempotentHandler.delMessageProcessed(msgId.toString());
            log.error("记录短链接监控消费异常", ex);
            throw ex;
        }
        messageQueueIdempotentHandler.setAccomplish(msgId.toString());
    }

}