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Hardhat

About​

Hardhat is an Ethereum development environment for professionals. It facilitates performing frequent tasks, such as running tests, automatically checking code for mistakes or interacting with a smart contract. Additionally, Hardhat is a comprehensive set of tools for creating Ethereum-based software, which includes various components that aid in editing, compiling, debugging, and deploying smart contracts and decentralized applications.

Initialization​

To be able to use the Hardhat functionalities, you will first have to initialize a Hardhat project. You can do so using the following commands:

$ npm init
$ npm install --save-dev hardhat @nomicfoundation/hardhat-ethers
$ npx hardhat init

For more details you can check out the official hardhat documentation page https://hardhat.org/hardhat-runner/docs/getting-started#installation

Deployment​

To deploy your contracts, you can use Hardhat Ignition. You can deploy the contract by using its accompanying Ignition module. An Ignition module is a TypeScript or JavaScript file that allows you to specify what needs to be deployed.

The Ignition module, is located under the ./ignition/modules directory and looks like this:

import { buildModule } from "@nomicfoundation/hardhat-ignition/modules";

const testModule = buildModule("Module", (m) => {

  const contract = m.contract("ContractName");

  return { contract };
});

export default testModule;

After double-checking that your private key is accessible to Hardhat and HamsterChain is correctly configured in hardhat.config.js, simply run the deployment script:

$ npx hardhat compile                                                                                    
Compiled 1 Solidity file successfully (evm target: cancun).
$ npx hardhat run --network hamsterChain scripts/deploy.js
Successfully deployed Contract to 0x...

Contract verification​

HamsterChain block explorer uses Blockscout's open-source technology and supports contract verification through the hardhat-verify plugin with an Etherscan-compatible API. For detailed instructions, refer to the "Smart Contract Verification" section.

To verify your smart contract, you should do the following steps.

info

Note that the hardhat-etherscan plugin is now hardhat-verify, which you need to install:

Firstly install the hardhat-verify library:

$ npm install --save-dev @nomicfoundation/hardhat-verify

Secondly update your hardhat.config.js file as follows:

require("@nomicfoundation/hardhat-ethers");
require("@nomicfoundation/hardhat-verify");

Configure the plugin, using "test" as the API key placeholder for Blockscout:

module.exports = {
    solidity: "0.8.25",
    networks: {
        hardhat: {},
        "hamsterChain": {
            url: "https://rpc.hamsterchain.org/",
            chainId: 11211,
            accounts: [process.env.PRIVATE_KEY]
        }
    },
    etherscan: {
        apiKey: {
            "hamsterChain": process.env.API_KEY
        },
        customChains: [
        {
            network: "hamsterChain",
            chainId: 11211,
            urls: {
                browserURL: "https://explorer.hamsterchain.org/"
            }
        }
        ]
    }
};

To verify your contract, save your constructor arguments (like the deployer's address) to an environment variable and run the verify command on the deployed contract address:

$ export DEPLOYER_ADDRESS=0x...                              
$ export CONTRACT_ADDRESS=0x...                              
$ npx hardhat verify --network hamsterChain \
$CONTRACT_ADDRESS $DEPLOYER_ADDRESS
info

You should see a message confirming successful verification and a link to the contract on the block explorer.