数据库缓存新年活动

# 示例代码：使用布隆过滤器防止缓存穿透
import pybloom_live

bloom = pybloom_live.BloomFilter(capacity=100000, error_rate=0.001)

def get_data(key):
    if key in bloom:
        data = cache.get(key)
        if data is None:
            data = db.query(key)
            if data is not None:
                cache.set(key, data, expire=60)
        return data
    else:
        return None

# 示例代码：使用互斥锁防止缓存击穿
import threading

lock = threading.Lock()

def get_hot_data(key):
    data = cache.get(key)
    if data is None:
        with lock:
            data = cache.get(key)  # 再次检查缓存
            if data is None:
                data = db.query(key)
                cache.set(key, data, expire=3600)
    return data

# 示例代码：设置随机过期时间防止缓存雪崩
import random

def set_cache(key, value):
    expire_time = 3600 + random.randint(-600, 600)  # 1小时±10分钟
    cache.set(key, value, expire=expire_time)