区块链：智能城市的"数字神经系统"——解密未来城市的三大可信变革

# 基于Hyperledger Fabric的跨部门数据共享智能合约
async def data_exchange(ctx, target_department, data_hash):
    # 验证请求方权限
    requester = ctx.clientIdentity.getMSPID()
    if not verify_permission(requester, target_department):
        return "Permission Denied"

    # 记录数据访问日志
    access_log = {
        "timestamp": datetime.utcnow().isoformat(),
        "data_hash": data_hash,
        "requester": requester,
        "provider": target_department
    }
    await ctx.stub.putState(f"LOG:{uuid4()}", json.dumps(access_log).encode())

    # 返回加密数据
    encrypted_data = decrypt_data(data_hash, ctx.clientIdentity.getID())
    return encrypted_data

// 基于以太坊的信用评分智能合约
contract CreditSystem {
    mapping(address => uint) public credits;
    address public admin;

    constructor() {
        admin = msg.sender;
    }

    // 城管上报违规事件
    function reportViolation(address user, string memory proof) public {
        require(msg.sender == admin, "Only admin");
        credits[user] -= 10;
        emit ViolationRecorded(user, proof, block.timestamp);
    }

    // 用户申诉
    function appeal(address inspector, string memory evidence) public {
        credits[msg.sender] += 5; // 申诉即奖励诚信行为
        emit AppealSubmitted(msg.sender, inspector, evidence);
    }
}

// 基于区块链的物联网设备协同预警
const { IoTChain } = require('iot-blockchain-sdk');

// 井盖传感器数据上链
async function reportWaterLevel(sensorId, level) {
    const tx = await IoTChain.sendTransaction({
        type: 'SENSOR_DATA',
        payload: {
            sensorId,
            level,
            location: '34.7526° N, 113.6608° E',
            timestamp: Date.now()
        }
    });
    
    if (level > DANGER_THRESHOLD) {
        const emergencyTx = await autoTriggerPump(tx.hash); 
        console.log('应急泵站已启动，交易哈希:', emergencyTx.hash);
    }
}

// 自动触发排水设备
async function autoTriggerPump(dataHash) {
    const contract = await IoTChain.loadContract('EmergencySystem');
    return contract.execute('activatePump', {
        dataHash,
        action: 'PUMP_001_ON'
    });
}

// 基于Substrate的市政设施管理模块
#[pallet::call]
impl<T: Config> Pallet<T> {
    #[pallet::weight(10_000)]
    pub fn register_asset(origin, 
        id: Vec<u8>,
        asset_type: AssetType,
        position: GPS,
        install_date: Moment
    ) -> DispatchResult {
        let sender = ensure_signed(origin)?;
        
        Assets::<T>::insert(
            &id,
            CityAsset {
                owner: sender,
                asset_type,
                position,
                install_date,
                maintenance_records: vec![]
            }
        );
        
        Self::deposit_event(Event::AssetRegistered(id));
        Ok(())
    }
}