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：在开发或维护solidity语言的智能合约时，经常会因为业务逻辑变动而变动合约内的逻辑，这就要考虑在不影响以前智能合约中已上链的数据的同时，修改或扩展新的业务逻辑，所以合约第一次开发时就需要考虑其本身支持可升级功能

目的：本篇文章是为了让读者快速上手使用hardhat并搭配openZeppelin的uups升级模式对合约进行可升级适配以及指导后续如何进行合约升级

适用对象：适用于BSN开放联盟链武汉链（基于ETH），也可适用于其他支持solidity语言的链框架

如何使用hardhat进行合约uups模式升级

安装hardhat
初始化项目
编写合约
编写测试文件
编辑配置文件
执行项目
参考

安装hardhat
1.创建空的文件夹demo-uups并进入文件夹里面，执行npm init
2.执行安装命令npm install --save-dev hardhat
3.安装依赖npm install --save-dev @nomiclabs/hardhat-waffle ethereum-waffle chai @nomiclabs/hardhat-ethers ethers
4.安装openZeppelin的uups可升级合约包 npm install --save-dev @openzeppelin/contracts-upgradeable
5.安装测试工具mocha npm install --save-dev mocha
初始化项目
执行npx hardhat选择Create a basic sample project

初始化完成后的目录结构为

编写合约

在contracts目录下面新建两个名称分别为MyLogicV1和MyLogicV2的.sol文件并进行代码编写。实现openZeppelin的uups升级模式必须要引入openZeppelin相关库文件，且必须在constructor()方法上加@custom:oz-upgrades-unsafe-allow constructor字样注释


// 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 constructorconstructor() 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 constructorconstructor() 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的写入方法和读取方法，MyLogicV2只是改写了MyLogicV1的GetLogic方法中的处理逻辑，使得每次返回的值加了100

编写测试文件
在test目录下创建生成名称为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方法以uups的方式部署MyLogicV1合约
myLogicV1 set：调用MyLogicV1合约中的SetLogic方法将值传入，并调用GetLogic方法确认返回值为1
upgrades：调用upgrades中的upgradeProxy方法升级
myLogicV2 get：调用MyLogicV2合约中的GetLogic方法确认返回值为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，测试说明成功升级改写了GetLogic中的处理逻辑，使得每次返回的值都在原来的基础上多加了100

参考

Hardhat官方文档：Overview | Hardhat | Ethereum development environment for professionals by Nomic Foundation[1]

OpenZeppelin官方文档：Using with Upgrades - OpenZeppelin Docs[2]

References

[1] Overview | Hardhat | Ethereum development environment for professionals by Nomic Foundation: https://hardhat.org/getting-started/
[2] Using with Upgrades - OpenZeppelin Docs: https://docs.openzeppelin.com/contracts/4.x/upgradeable