redis lua脚本解决高并发下秒杀场景

CREATE TABLE `tb_product` (
  `id` bigint NOT NULL AUTO_INCREMENT,
  `product_id` varchar(128) NOT NULL DEFAULT '' COMMENT 'id',
   `price` decimal(65,18) NOT NULL DEFAULT '0',
   `available_qty` bigint NOT NULL DEFAULT '0' COMMENT '发行数量',
  `title` varchar(1024) NOT NULL DEFAULT '',
   `end_time` bigint NOT NULL DEFAULT '0',
  `start_time` bigint NOT NULL DEFAULT '0',
  `created` bigint NOT NULL DEFAULT '0',
  `updated` bigint NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`),
  UNIQUE KEY `uq_product_id` (`product_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb3;

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>

private final static DefaultRedisScript<Long> deductRedisScript = new DefaultRedisScript();
    private final static DefaultRedisScript<Long> increaseRedisScript = new DefaultRedisScript();   
//加载lua脚本
    @PostConstruct
    void init() {
        //加载削减库存lua脚本
        deductRedisScript.setScriptSource(new ResourceScriptSource(new ClassPathResource("redis/fixedDeductInventory.lua")));
        deductRedisScript.setResultType(Long.class);
        //加载库存回滚lua脚本
        increaseRedisScript.setScriptSource(new ResourceScriptSource(new ClassPathResource("redis/fixedIncreaseInventory.lua")));
        increaseRedisScript.setResultType(Long.class);
    }

@Resource(name = "fixedCacheRedisTemplate")
    private RedisTemplate<String, Long> fixedCacheRedisTemplate;
public void ProductToOngoing(Product data, Long time) {
         //设置数量
            long number = data.getAvailableQty();
            fixedCacheRedisTemplate.opsForHash().putIfAbsent("{fixed:" + data.getProductId() + "}-residue_stock_" + data.getRecordId(),
                    "{fixed:" + data.getProductId() + "}-residueStock" , number);
            String statusKey = "fixed_product_sold_status_"+ data.getRecordId();
            long timeout = data.getEndTime() - data.getStartTime();
              //添加产品出售状态
            fixedCacheRedisTemplate.opsForValue().set(statusKey, 1L, data.getEndTime() - data.getStartTime(), TimeUnit.MILLISECONDS);
    }

//检查库存
public boolean checkFixedOrderQty(Long userId, Long productId, Long quantity, Long overTime) {
        Boolean pendingOrder = false;
        String userKey = "";
        try {
            //校验是否开始
            String statusKey = "fixed_product_sold_status_" + productId;
            Long fixedStartStatus = fixedCacheRedisTemplate.opsForValue().get(statusKey);
            if (fixedStartStatus == null || fixedStartStatus != 1L) {
                //报错返回，商品未开售
                throw new WebException(ResultCode.SALE_HAS_NOT_START);
            }
              //检查库存数量
            Long number = deductInventory(productId, quantity);
            if (number != 1L) {
                log.warn("availbale num is null:{} {}", productId, number);
                throw new WebException(ResultCode.AVAILABLE_AMOUNT_INSUFFICIENT);
            }
            return true;
        } catch (Exception e) {
            log.warn("checkFixedOrderQty error:{}", e.getMessage(), e);
            throw e;
        }
    }
//下单
 public void createOrder(Long userId, Long productId, BigDecimal price, Long quantity){
     boolean check = checkFixedOrderQty(userId, productId, quantity);
        try {
            if (check) {
                //添加MQ等待下单，后续收到推送的线程保存靠DB中
                CreateCoinOrderData data = new CreateCoinOrderData();
                data.setUserId(userId);
                data.setProductId(productId);
                data.setPrice(price);
                data.setQuantity(quantity);
                rabbitmqProducer.sendMessage(1, JSONObject.toJSONString(data));
            }
        } catch (Exception e) {
            //发生异常，库存需要回滚
            increaseInventory(recordId, quantity, 1L);
            throw e;
        }
 }
    //库存回填
    public Long increaseInventory(Long productId, Long num) {
        try {
            // 构建keys信息，代表hash值中所需要的key信息
            List<String> keys = Arrays.asList("{fixed:" + productId + "}-residue_stock_"+ recordId, "{fixed:" + productId + "}-residueStock");
            // 执行脚本
            Object result = fixedCacheRedisTemplate.execute(increaseRedisScript, keys, num);
            log.info("increaseInventory productId :{} num:{}  result:{}", productId, num, result);
            return (Long) result;
        } catch (Exception e) {
            log.warn("increaseInventory error productId:{}  num:{}", productId, num);
        }
        return 0L;
    }