区块链技术在供应链管理中的透明性与可追溯性研究

// 供应链智能合约示例
pragma solidity ^0.8.0;
 
contract SupplyChain {
    struct Product {
        uint productId;
        string productName;
        address manufacturer;
        address distributor;
        address retailer;
        bool isVerified;
    }
 
    mapping(uint => Product) public products;
    uint public productCount;
 
    // 添加产品到供应链
    function addProduct(string memory _productName) public {
        productCount++;
        products[productCount] = Product(productCount, _productName, msg.sender, address(0), address(0), false);
    }
 
    // 确认产品发货
    function shipProduct(uint _productId, address _distributor) public {
        require(products[_productId].manufacturer == msg.sender, "Only manufacturer can ship the product");
        products[_productId].distributor = _distributor;
    }
 
    // 确认产品到达
    function receiveProduct(uint _productId) public {
        require(products[_productId].distributor == msg.sender, "Only distributor can receive the product");
        products[_productId].isVerified = true;
    }
}

from web3 import Web3
 
# 连接到以太坊节点
web3 = Web3(Web3.HTTPProvider('http://localhost:8545'))
 
# 加载智能合约 ABI 和地址
contract_address = '0x123456789...'
contract_abi = [...]  # 合约 ABI
 
supply_chain = web3.eth.contract(address=contract_address, abi=contract_abi)
 
def get_product_history(product_id):
    product = supply_chain.functions.products(product_id).call()
    history = {
        'productId': product[0],
        'productName': product[1],
        'manufacturer': product[2],
        'distributor': product[3],
        'retailer': product[4],
        'isVerified': product[5]
    }
    return history
 
# 查询产品 ID 为 1 的历史记录
product_history = get_product_history(1)
print(product_history)