关于区块链:如何使用hardhat进行合约uups模式升级

id:BSN_2021
公众号：BSN研习社

背景：在开发或保护solidity语言的智能合约时，常常会因为业务逻辑变动而变动合约内的逻辑，这就要思考在不影响以前智能合约中已上链的数据的同时，批改或扩大新的业务逻辑，所以合约第一次开发时就须要思考其自身反对可降级性能

目标：本篇文章是为了让读者疾速上手应用hardhat并搭配openZeppelin的uups降级模式对合约进行可降级适配以及领导后续如何进行合约降级

实用对象：实用于BSN凋谢联盟链武汉链（基于ETH），也可实用于其余反对solidity语言的链框架

如何应用hardhat进行合约uups模式降级

• 装置hardhat
• 初始化我的项目
• 编写合约
• 编写测试文件
• 编辑配置文件
• 执行我的项目
• 参考

装置hardhat
1.创立空的文件夹demo-uups并进入文件夹外面，执行npm init
2.执行装置命令npm install –save-dev hardhat
3.装置依赖npm install –save-dev @nomiclabs/hardhat-waffle ethereum-waffle chai @nomiclabs/hardhat-ethers ethers
4.装置openZeppelin的uups可降级合约包 npm install –save-dev @openzeppelin/contracts-upgradeable
5.装置测试工具mocha npm install –save-dev mocha
初始化我的项目
执行npx hardhat抉择Create a basic sample project

初始化实现后的目录构造为
编写合约
在contracts目录上面新建两个名称别离为MyLogicV1和MyLogicV2的.sol文件并进行代码编写。实现openZeppelin的uups降级模式必须要引入openZeppelin相干库文件，且必须在constructor()办法上加@custom:oz-upgrades-unsafe-allow constructor字样正文

// contract/MyLogicV1.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/utils/UUPSUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";

contract MyLogicV1 is Initializable, UUPSUpgradeable, OwnableUpgradeable {
    function initialize() initializer public {
      __Ownable_init();
      __UUPSUpgradeable_init();
    }

    /// @custom:oz-upgrades-unsafe-allow constructor
    constructor() initializer {}

    function _authorizeUpgrade(address) internal override onlyOwner {}

    mapping(string => uint256) private logic;

    event logicSetted(string indexed _key, uint256 _value);

    function SetLogic(string memory _key, uint256 _value) external {
        logic[_key] = _value;
        emit logicSetted(_key, _value);
    }

    function GetLogic(string memory _key) public view returns (uint256){
        return logic[_key];
    }
}

// contract/MyLogicV2.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/utils/UUPSUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";

contract MyLogicV2 is Initializable, UUPSUpgradeable, OwnableUpgradeable {
    function initialize() initializer public {
      __Ownable_init();
      __UUPSUpgradeable_init();
    }

    /// @custom:oz-upgrades-unsafe-allow constructor
    constructor() initializer {}

    function _authorizeUpgrade(address) internal override onlyOwner {}

    mapping(string => uint256) private logic;

    event logicSetted(string indexed _key, uint256 _value);

    function SetLogic(string memory _key, uint256 _value) external {
        logic[_key] = _value;
        emit logicSetted(_key, _value);
    }

    function GetLogic(string memory _key) public view returns (uint256){
        return logic[_key]+100;
    }
}

MyLogicV1实现了一个对于logic的map的写入办法和读取办法，MyLogicV2只是改写了MyLogicV1的GetLogic办法中的解决逻辑，使得每次返回的值加了100

编写测试文件
在test目录下创立生成名称为update-test的.js文件并进行代码编写

// test/update-test.ts
const { expect } = require('chai');
const { ethers, upgrades } = require('hardhat');


let myLogicV1;
let myLogicV2;

describe('uups mode upgrade', function () {
  it('deploys', async function () {
    const MyLogicV1 = await ethers.getContractFactory('MyLogicV1');
      myLogicV1 = (await upgrades.deployProxy(MyLogicV1, {kind: 'uups'}));
      console.log(myLogicV1.address);
  })
  it('myLogicV1 set', async function () {
    await myLogicV1.SetLogic("aa", 1);
    expect((await myLogicV1.GetLogic("aa")).toString()).to.equal('1');
  })
  it('upgrades', async function () {
    const MyLogicV2 = await ethers.getContractFactory('MyLogicV2');
      myLogicV2 = (await upgrades.upgradeProxy(myLogicV1, MyLogicV2));
      console.log(myLogicV2.address);
  })
  it('myLogicV2 get', async function () {
      expect((await myLogicV2.GetLogic("aa")).toString()).to.equal('101');
  })
})

测试文件步骤详解

• deploys: 调用upgrades中的deployProxy办法以uups的形式部署MyLogicV1合约
• myLogicV1 set：调用MyLogicV1合约中的SetLogic办法将值传入，并调用GetLogic办法确认返回值为1
• upgrades：调用upgrades中的upgradeProxy办法降级
• myLogicV2 get：调用MyLogicV2合约中的GetLogic办法确认返回值为101

编辑配置文件
编辑hardhat.config.js文件

require("@nomiclabs/hardhat-waffle");
require('@openzeppelin/hardhat-upgrades');

// This is a sample Hardhat task. To learn how to create your own go to
// https://hardhat.org/guides/create-task.html
task("accounts", "Prints the list of accounts", async (taskArgs, hre) => {
  const accounts = await hre.ethers.getSigners();

  for (const account of accounts) {
    console.log(account.address);
  }
});

// You need to export an object to set up your config
// Go to https://hardhat.org/config/ to learn more

/**
 * @type import('hardhat/config').HardhatUserConfig
 */
module.exports = {
  solidity: {
    version: "0.8.4",
    settings: {
      optimizer: {
        enabled: true,
        runs: 200
      }
    }
  },
  mocha: { timeout: 60000 }
};

执行我的项目
1.执行编译合约
npx hardhat compile

2.启动本地测试节点
npx hardhat node

3.新开一个窗口运行测试文件
npx hardhat test test/update-test.js –network localhost

测试通过，合约地址都为代理合约地址，测试阐明胜利降级改写了GetLogic中的解决逻辑，使得每次返回的值都在原来的根底上多加了100

参考
Hardhat官网文档：Overview | Hardhat | Ethereum development environment for professionals by Nomic Foundation[1]

OpenZeppelin官网文档：Using with Upgrades – OpenZeppelin Docs[2]

References
[1] Overview | Hardhat | Ethereum development environment for professionals by Nomic Foundation: https://hardhat.org/getting-s…
[2] Using with Upgrades – OpenZeppelin Docs: https://docs.openzeppelin.com…