[中间件] 秒杀系统秒杀率提高300%？教你如何利用redis和rabbitmq 优化应用！

@Component
public class SecKillService {
    @Autowired
    private RedisTemplate<String, String> redisTemplate;
    public boolean secKill(String itemId, String userId) {
        // 从redis中获取商品库存
        String stock = redisTemplate.opsForValue().get("stock:" + itemId);
        if (stock == null || Integer.parseInt(stock) <= 0) {
            return false;
        }
        // 库存减一
        Long result = redisTemplate.opsForValue().decrement("stock:" + itemId);
        if (result < 0) {
            redisTemplate.opsForValue().increment("stock:" + itemId);
            return false;
        }
        // 记录用户购买记录
        redisTemplate.opsForSet().add("user:" + userId + ":purchases", itemId);
        return true;
    }
}

@Component
public class RateLimiter {
    @Autowired
    private RedisTemplate<String, String> redisTemplate;
    public boolean acquire(String key, int capacity, int rate) {
        String tokenCount = redisTemplate.opsForValue().get(key);
        if (tokenCount == null) {
            redisTemplate.opsForValue().set(key, String.valueOf(capacity));
            redisTemplate.expire(key, 1, TimeUnit.SECONDS);
            return true;
        }
        int count = Integer.parseInt(tokenCount);
        if (count <= 0) {
            return false;
        }
        redisTemplate.opsForValue().set(key, String.valueOf(count - 1));
        redisTemplate.expire(key, 1, TimeUnit.SECONDS);
        return true;
    }
}

@Component
public class SecKillSender{
    @Autowired
    private RabbitTemplate rabbitTemplate;
    public void send(String itemId, String userId) {
        rabbitTemplate.convertAndSend("secKillExchange", "secKillRoutingKey", itemId + ":" + userId);
    }
}

@Component
@RabbitListener(queues = "secKillQueue")
public class SecKillReceiver {
    @Autowired
    private SecKillService secKillService;
    @RabbitHandler
    public void process(String message) {
        String[] values = message.split(":");
        String itemId = values[0];
        String userId = values[1];
        secKillService.secKill(itemId, userId);
    }
}