现在我们来实践hardhat部署合约中的其他更多技术要点

1. 代码方式验证合约

• 注册https://etherscan.io/, 如下图添加拷贝API_KEY

• 在.env文件中新增ETHERSCAN_API_KEY

ETHERSCAN_API_KEY=API_KEY【刚才注册的key】

• hardhat.config.js中新增配置

const ETHERSCAN_API_KEY = process.env.ETHERSCAN_API_KEY

module.exports = {
  etherscan: {
    apiKey: ETHERSCAN_API_KEY
  }
};

• 覆盖deploy.js

// imports
const { ethers, run, network } = require("hardhat")

// async main
async function main() {
  const SimpleStorageFactory = await ethers.getContractFactory("SimpleStorage")
  console.log("Deploying contract...")
  const simpleStorage = await SimpleStorageFactory.deploy()
  await simpleStorage.deployed()
  console.log(`Deployed contract to: ${simpleStorage.address}`)
   if (network.config.chainId === 5 && process.env.ETHERSCAN_API_KEY) {
    console.log("Waiting for block confirmations...")
    await simpleStorage.deployTransaction.wait(6)
    await verify(simpleStorage.address, [])
  }
}

const verify = async (contractAddress, args) => {
  console.log("Verifying contract...")
  try {
    await run("verify:verify", {
      address: contractAddress,
      constructorArguments: args,
    })
  } catch (e) {
    if (e.message.toLowerCase().includes("already verified")) {
      console.log("Already Verified!")
    } else {
      console.log(e)
    }
  }
}

// main
main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error)
    process.exit(1)
})

• 验证合约

如果用的使用了clash代理的话开启Tun模式，否则可能会报Connect Timeout Error

yarn hardhat run scripts/deploy.js --network goerli
或
yarn hardhat verify --network goerli 0x2e3C64c769DAbAC7587dEa70cA23164EEE3d9596 --show-stack-traces

yarn run v1.22.19
$ D:\blockchain\blockchain\hardhat-simple-storage-fcc\node_modules\.bin\hardhat verify --network goerli 0x2e3C64c769DAbAC7587dEa70cA23164EEE3d9596 --show-stack-traces
Nothing to compile
Successfully submitted source code for contract
contracts/SimpleStorage.sol:SimpleStorage at 0x2e3C64c769DAbAC7587dEa70cA23164EEE3d9596
for verification on the block explorer. Waiting for verification result...

Successfully verified contract SimpleStorage on Etherscan.
https://goerli.etherscan.io/address/0x2e3C64c769DAbAC7587dEa70cA23164EEE3d9596#code
Done in 30.38s.

2. 通过hardhat与合约交互

在deploy.js的main方法中新增如下代码

async function main() {
  ......
  const currentValue = await simpleStorage.retrieve()
  console.log(`Current Value is: ${currentValue}`)

  // Update the current value
  const transactionResponse = await simpleStorage.store(7)
  await transactionResponse.wait(1)
  const updatedValue = await simpleStorage.retrieve()
  console.log(`Updated Value is: ${updatedValue}`)
}

运行及结果展示：

(base) PS D:\blockchain\blockchain\hardhat-simple-storage-fcc> yarn hardhat run scripts/deploy.js                          
yarn run v1.22.19
$ D:\blockchain\blockchain\hardhat-simple-storage-fcc\node_modules\.bin\hardhat run scripts/deploy.js
Deploying contract...
Deployed contract to: 0x5FbDB2315678afecb367f032d93F642f64180aa3
Current Value is: 0
Updated Value is: 7
Done in 3.62s.

3.自定义hardhat任务

• 新建tasks/block-number.js

const { task } = require("hardhat/config")

task("block-number", "Prints the current block number").setAction(
  async (taskArgs, hre) => {
    const blockNumber = await hre.ethers.provider.getBlockNumber()
    console.log(`Current block number: ${blockNumber}`)
  }
)

module.exports = {}

• 在hardhat.config.js中新增配置

require("./tasks/block-number")

• 运行yarn hardhat命令

// 可以看到出现了任务
AVAILABLE TASKS:
  block-number          Prints the current block number

• 运行yarn hardhat block-number --network goerli查看最新区块号

(base) PS D:\blockchain\blockchain\hardhat-simple-storage-fcc> yarn hardhat block-number --network goerli
yarn run v1.22.19
$ D:\blockchain\blockchain\hardhat-simple-storage-fcc\node_modules\.bin\hardhat block-number --network goerli
Current block number: 7779125
Done in 14.01s.

4.hardhat本地节点

• 运行yarn hardhat node查看本地节点信息

(base) PS D:\blockchain\blockchain\hardhat-simple-storage-fcc> yarn hardhat node
yarn run v1.22.19
$ D:\blockchain\blockchain\hardhat-simple-storage-fcc\node_modules\.bin\hardhat node
Started HTTP and WebSocket JSON-RPC server at http://127.0.0.1:8545/

Accounts
========

WARNING: These accounts, and their private keys, are publicly known.
Any funds sent to them on Mainnet or any other live network WILL BE LOST.

Account #0: 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266 (10000 ETH)
Private Key: 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80

Account #1: 0x70997970C51812dc3A010C7d01b50e0d17dc79C8 (10000 ETH)
Private Key: 0x59c6995e998f97a5a0044966f0945389dc9e86dae88c7a8412f4603b6b78690d

• 在hardhat.config.js中新增网络配置

module.exports = {
  networks: {
    localhost: {
      url: "http://127.0.0.1:8545/",
      chainId: 31337
    }
  }
};

• 新启动shell窗口并运行yarn hardhat run scripts/deploy.js --network localhost

(base) PS D:\blockchain\blockchain\hardhat-simple-storage-fcc> yarn hardhat run scripts/deploy.js --network localhost       
yarn run v1.22.19
$ D:\blockchain\blockchain\hardhat-simple-storage-fcc\node_modules\.bin\hardhat run scripts/deploy.js --network localhost
Deploying contract...
Deployed contract to: 0x5FbDB2315678afecb367f032d93F642f64180aa3
Current Value is: 0
Updated Value is: 7

• 切换到node窗口可看到本地交易信息

• 在新启动的shell窗口中运行yarn hardhat console --network localhost我们即可在控制台与合约交互

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