怎么更新服务器缓存

# 示例代码：主动更新缓存
def update_data_in_cache(key, new_value):
    cache.delete(key)  # 删除旧缓存
    cache.set(key, new_value)  # 设置新缓存

# 示例代码：使用分布式锁
from redis import Redis
import time

redis_client = Redis()

def update_cache_with_lock(key, new_value):
    lock_key = f"lock:{key}"
    if redis_client.setnx(lock_key, "1"):  # 尝试加锁
        redis_client.expire(lock_key, 10)  # 设置锁的过期时间
        try:
            cache.delete(key)  # 删除旧缓存
            cache.set(key, new_value)  # 设置新缓存
        finally:
            redis_client.delete(lock_key)  # 释放锁
    else:
        time.sleep(0.1)  # 等待一段时间后重试

# 示例代码：缓存空值
def get_data(key):
    data = cache.get(key)
    if data is None:
        data = db.query(key)  # 查询数据库
        if data is None:
            cache.set(key, "null", timeout=60)  # 缓存空值
        else:
            cache.set(key, data, timeout=3600)  # 缓存数据
    return data