Redis在智能家居系统中的作用及应用案例

import redis

# 连接Redis
r = redis.Redis(host='localhost', port=6379, db=0)

# 保存设备状态
def save_device_status(device_id, status):
    r.hset("devices", device_id, status)

# 获取设备状态
def get_device_status(device_id):
    return r.hget("devices", device_id)

# 示例代码，设置设备1状态为开
save_device_status(1, "开")

# 示例代码，获取设备1状态
status = get_device_status(1)
print(status)

import redis
import time

# 连接Redis
r = redis.Redis(host='localhost', port=6379, db=0)

# 获取锁
def acquire_lock(lock_name, acquire_timeout=10):
    end_time = time.time() + acquire_timeout
    while time.time() < end_time:
        if r.setnx(lock_name, 1):
            r.expire(lock_name, acquire_timeout)
            return True
        time.sleep(0.001)
    return False

# 释放锁
def release_lock(lock_name):
    r.delete(lock_name)

# 示例代码，设备1想要操作设备2
device1 = 1
device2 = 2

# 设备1获取锁
if acquire_lock(device2):
    # 操作设备2...
    # 释放锁
    release_lock(device2)
else:
    # 获取锁失败
    print("获取锁失败")

import redis

# 连接Redis
r = redis.Redis(host='localhost', port=6379, db=0)

# 订阅设备状态变化的频道
def subscribe_channel():
    pubsub = r.pubsub()
    pubsub.subscribe('device_status')

    for item in pubsub.listen():
        if item['type'] == 'message':
            device_id, status = item['data'].decode().split(':')
            print("设备{}的状态变为{}".format(device_id, status))

# 示例代码，设备1的状态变为开，发布消息
r.publish('device_status', '1:开')

# 订阅设备状态变化的频道，接收消息并打印
subscribe_channel()