import aioredis
import json

class DeviceService:
    def __init__(self):
        self.redis = aioredis.from_url("redis://localhost")

    async def get_device_connection(self, user_id):
        """获取设备连接信息"""
        key = f"device_connection:{user_id}"
        return await self.redis.get(key)

    async def set_device_connection(self, user_id, connection_info):
        """设置设备连接信息"""
        key = f"device_connection:{user_id}"
        await self.redis.set(key, json.dumps(connection_info))

    async def remove_device_connection(self, user_id):
        """移除设备连接信息"""
        key = f"device_connection:{user_id}"
        await self.redis.delete(key)