21.秒杀服务
1.上架三天需要秒杀的商品
@Override
public void uploadSeckillSkuLatest3Days() {
//1、扫描最近三天的商品需要参加秒杀的活动
R lates3DaySession = couponFeignService.getLates3DaySession();
if (lates3DaySession.getCode() == 0) {
//上架商品
List<SeckillSessionWithSkusVo> sessionData = lates3DaySession.getData("data", new TypeReference<List<SeckillSessionWithSkusVo>>() {
});
//缓存到Redis
//1、缓存活动信息
saveSessionInfos(sessionData);
//2、缓存活动的关联商品信息
saveSessionSkuInfo(sessionData);
}
}2.缓存秒杀活动信息
private void saveSessionInfos(List<SeckillSessionWithSkusVo> sessions) {
sessions.stream().forEach(session -> {
//获取当前活动的开始和结束时间的时间戳
long startTime = session.getStartTime().getTime();
long endTime = session.getEndTime().getTime();
//存入到Redis中的key
String key = SESSION__CACHE_PREFIX + startTime + "_" + endTime;
//判断Redis中是否有该信息，如果没有才进行添加
Boolean hasKey = redisTemplate.hasKey(key);
//缓存活动信息
if (!hasKey) {
//获取到活动中所有商品的skuId
List<String> skuIds = session.getRelationSkus().stream()
.map(item -> item.getPromotionSessionId() + "-" + item.getSkuId().toString()).collect(Collectors.toList());
redisTemplate.opsForList().leftPushAll(key,skuIds);
}
});
}3.缓存秒杀活动所关联的商品信息
private void saveSessionSkuInfo(List<SeckillSessionWithSkusVo> sessions) {
sessions.stream().forEach(session -> {
//准备hash操作，绑定hash
BoundHashOperations<String, Object, Object> operations = redisTemplate.boundHashOps(SECKILL_CHARE_PREFIX);
session.getRelationSkus().stream().forEach(seckillSkuVo -> {
//生成随机码
String token = UUID.randomUUID().toString().replace("-", "");
String redisKey = seckillSkuVo.getPromotionSessionId().toString() + "-" + seckillSkuVo.getSkuId().toString();
if (!operations.hasKey(redisKey)) {
//缓存我们商品信息
SeckillSkuRedisTo redisTo = new SeckillSkuRedisTo();
Long skuId = seckillSkuVo.getSkuId();
//1、先查询sku的基本信息，调用远程服务
R info = productFeignService.getSkuInfo(skuId);
if (info.getCode() == 0) {
SkuInfoVo skuInfo = info.getData("skuInfo",new TypeReference<SkuInfoVo>(){});
redisTo.setSkuInfo(skuInfo);
}
//2、sku的秒杀信息
BeanUtils.copyProperties(seckillSkuVo,redisTo);
//3、设置当前商品的秒杀时间信息
redisTo.setStartTime(session.getStartTime().getTime());
redisTo.setEndTime(session.getEndTime().getTime());
//4、设置商品的随机码（防止恶意攻击）
redisTo.setRandomCode(token);
//序列化json格式存入Redis中
String seckillValue = JSON.toJSONString(redisTo);
operations.put(seckillSkuVo.getPromotionSessionId().toString() + "-" + seckillSkuVo.getSkuId().toString(),seckillValue);
//如果当前这个场次的商品库存信息已经上架就不需要上架
//5、使用库存作为分布式Redisson信号量（限流）
// 使用库存作为分布式信号量
RSemaphore semaphore = redissonClient.getSemaphore(SKU_STOCK_SEMAPHORE + token);
// 商品可以秒杀的数量作为信号量
semaphore.trySetPermits(seckillSkuVo.getSeckillCount());
}
});
});
}4.获取到当前可以参加秒杀商品的信息
@SentinelResource(value = "getCurrentSeckillSkusResource",blockHandler = "blockHandler")
@Override
public List<SeckillSkuRedisTo> getCurrentSeckillSkus() {
try (Entry entry = SphU.entry("seckillSkus")) {
//1、确定当前属于哪个秒杀场次
long currentTime = System.currentTimeMillis();
//从Redis中查询到所有key以seckill:sessions开头的所有数据
Set<String> keys = redisTemplate.keys(SESSION__CACHE_PREFIX + "*");
for (String key : keys) {
//seckill:sessions:1594396764000_1594453242000
String replace = key.replace(SESSION__CACHE_PREFIX, "");
String[] s = replace.split("_");
//获取存入Redis商品的开始时间
long startTime = Long.parseLong(s[0]);
//获取存入Redis商品的结束时间
long endTime = Long.parseLong(s[1]);
//判断是否是当前秒杀场次
if (currentTime >= startTime && currentTime <= endTime) {
//2、获取这个秒杀场次需要的所有商品信息
List<String> range = redisTemplate.opsForList().range(key, -100, 100);
BoundHashOperations<String, String, String> hasOps = redisTemplate.boundHashOps(SECKILL_CHARE_PREFIX);
assert range != null;
List<String> listValue = hasOps.multiGet(range);
if (listValue != null && listValue.size() >= 0) {
List<SeckillSkuRedisTo> collect = listValue.stream().map(item -> {
String items = (String) item;
SeckillSkuRedisTo redisTo = JSON.parseObject(items, SeckillSkuRedisTo.class);
// redisTo.setRandomCode(null);当前秒杀开始需要随机码
return redisTo;
}).collect(Collectors.toList());
return collect;
}
break;
}
}
} catch (BlockException e) {
log.error("资源被限流{}",e.getMessage());
}
return null;
}5.根据skuId查询商品是否参加秒杀活动
@Override
public SeckillSkuRedisTo getSkuSeckilInfo(Long skuId) {
//1、找到所有需要秒杀的商品的key信息---seckill:skus
BoundHashOperations<String, String, String> hashOps = redisTemplate.boundHashOps(SECKILL_CHARE_PREFIX);
//拿到所有的key
Set<String> keys = hashOps.keys();
if (keys != null && keys.size() > 0) {
//4-45 正则表达式进行匹配
String reg = "\\d-" + skuId;
for (String key : keys) {
//如果匹配上了
if (Pattern.matches(reg,key)) {
//从Redis中取出数据来
String redisValue = hashOps.get(key);
//进行序列化
SeckillSkuRedisTo redisTo = JSON.parseObject(redisValue, SeckillSkuRedisTo.class);
//随机码
Long currentTime = System.currentTimeMillis();
Long startTime = redisTo.getStartTime();
Long endTime = redisTo.getEndTime();
//如果当前时间大于等于秒杀活动开始时间并且要小于活动结束时间
if (currentTime >= startTime && currentTime <= endTime) {
return redisTo;
}
redisTo.setRandomCode(null);
return redisTo;
}
}
}
return null;
}6. 当前商品进行秒杀（秒杀开始）
@Override
public String kill(String killId, String key, Integer num) throws InterruptedException {
long s1 = System.currentTimeMillis();
//获取当前用户的信息
MemberResponseVo user = LoginUserInterceptor.loginUser.get();
//1、获取当前秒杀商品的详细信息从Redis中获取
BoundHashOperations<String, String, String> hashOps = redisTemplate.boundHashOps(SECKILL_CHARE_PREFIX);
String skuInfoValue = hashOps.get(killId);
if (StringUtils.isEmpty(skuInfoValue)) {
return null;
}
//(合法性效验)
SeckillSkuRedisTo redisTo = JSON.parseObject(skuInfoValue, SeckillSkuRedisTo.class);
Long startTime = redisTo.getStartTime();
Long endTime = redisTo.getEndTime();
long currentTime = System.currentTimeMillis();
//判断当前这个秒杀请求是否在活动时间区间内(效验时间的合法性)
if (currentTime >= startTime && currentTime <= endTime) {
//2、效验随机码和商品id
String randomCode = redisTo.getRandomCode();
String skuId = redisTo.getPromotionSessionId() + "-" +redisTo.getSkuId();
if (randomCode.equals(key) && killId.equals(skuId)) {
//3、验证购物数量是否合理和库存量是否充足
Integer seckillLimit = redisTo.getSeckillLimit();
//获取信号量
String seckillCount = redisTemplate.opsForValue().get(SKU_STOCK_SEMAPHORE + randomCode);
Integer count = Integer.valueOf(seckillCount);
//判断信号量是否大于0,并且买的数量不能超过库存
if (count > 0 && num <= seckillLimit && count > num ) {
//4、验证这个人是否已经买过了（幂等性处理）,如果秒杀成功，就去占位。userId-sessionId-skuId
//SETNX 原子性处理
String redisKey = user.getId() + "-" + skuId;
//设置自动过期(活动结束时间-当前时间)
Long ttl = endTime - currentTime;
Boolean aBoolean = redisTemplate.opsForValue().setIfAbsent(redisKey, num.toString(), ttl, TimeUnit.MILLISECONDS);
if (aBoolean) {
//占位成功说明从来没有买过,分布式锁(获取信号量-1)
RSemaphore semaphore = redissonClient.getSemaphore(SKU_STOCK_SEMAPHORE + randomCode);
//TODO 秒杀成功，快速下单
boolean semaphoreCount = semaphore.tryAcquire(num, 100, TimeUnit.MILLISECONDS);
//保证Redis中还有商品库存
if (semaphoreCount) {
//创建订单号和订单信息发送给MQ
// 秒杀成功 快速下单 发送消息到 MQ 整个操作时间在 10ms 左右
String timeId = IdWorker.getTimeId();
SeckillOrderTo orderTo = new SeckillOrderTo();
orderTo.setOrderSn(timeId);
orderTo.setMemberId(user.getId());
orderTo.setNum(num);
orderTo.setPromotionSessionId(redisTo.getPromotionSessionId());
orderTo.setSkuId(redisTo.getSkuId());
orderTo.setSeckillPrice(redisTo.getSeckillPrice());
rabbitTemplate.convertAndSend("order-event-exchange","order.seckill.order",orderTo);
long s2 = System.currentTimeMillis();
log.info("耗时..." + (s2 - s1));
return timeId;
}
}
}
}
}
long s3 = System.currentTimeMillis();
log.info("耗时..." + (s3 - s1));
return null;
}
