Okay so after some digging around, I’ve made the decision on the 21st day of my journey into Web3 that I’ll be sticking to Hardhat for full stack dApp development.

At this point, I literally know nothing about Hardhat.

No matter. My first step is to use the Hardhat documentation.

Basics of Hardhat

Installing Hardhat

npm init npm install --save-dev hardhat

Creating a Hardhat project

npx hardhat

Getting the available commands

npx hardhat in project folder

Getting the accounts

npx hardhat accounts

Compiling, testing, deploying

Compiling all the contracts in the ‘contracts/’ folder

npx hardhat compile

Running the tests in test folder*

npm hardhat test

*This is what the test file, sample-test.js looks like. This is a classic javascript test file.

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const { expect } = require("chai");
const { ethers } = require("hardhat");

describe("Greeter", function () {
  it("Should return the new greeting once it's changed", async function () {
    const Greeter = await ethers.getContractFactory("Greeter");
    const greeter = await Greeter.deploy("Hello, world!");
    await greeter.deployed();

    expect(await greeter.greet()).to.equal("Hello, world!");

    const setGreetingTx = await greeter.setGreeting("Hola, mundo!");

    // wait until the transaction is mined
    await setGreetingTx.wait();

    expect(await greeter.greet()).to.equal("Hola, mundo!");
  });
});

Deploying the contracts

To deploy contracts, we use the Hardhat script. It is inside ‘scripts’ folder. npx hardhat run scripts/sample-script.js

sample-scripts.js looks like this:

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// We require the Hardhat Runtime Environment explicitly here. This is optional
// but useful for running the script in a standalone fashion through `node <script>`.
//
// When running the script with `npx hardhat run <script>` you'll find the Hardhat
// Runtime Environment's members available in the global scope.

const hre = require("hardhat");

async function main() {
  // Hardhat always runs the compile task when running scripts with its command
  // line interface.
  //
  // If this script is run directly using `node` you may want to call compile
  // manually to make sure everything is compiled
  // await hre.run('compile');

  // We get the contract to deploy
  const Greeter = await hre.ethers.getContractFactory("Greeter");
  const greeter = await Greeter.deploy("Hello, Hardhat!");

  await greeter.deployed();

  console.log("Greeter deployed to:", greeter.address);
}

// We recommend this pattern to be able to use async/await everywhere
// and properly handle errors.
main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

So here, the main thing that happens is that the async main function runs. Before that, the hre actually refers to the hardhat runtime environment. It says in the comments that this is actually optional, but it’s required when you want to run the script in a standalone fashion using node <script>. Cool.

Within the code, the hre.ethers object allows us to get contract factory, and we deploy the contract supplying “Hello Hardhat!” as argument. We wait for it to be deployed, and then we print the greeter address. Pretty intuitive, apart from some of the methods of the hre object, and the deploy() method.

On Hardhat network

Hardhat always spins up an in-memory instance of Hardhat Network on startup by default.

You can also run a Hardhat network in a standalone fashion so that external clients can connect to it - it could be Metamask, Dapp front-end, or a script.

Running Hardhat network as standalone:

npx hardhat node This will expose a JSON-RPC interface to Hardhat network. To use it, connect your wallet or app to http://localhost:8545.

If you want to connect hardhat to this node to run a deployment script against it, you’ll neeed to add --network localhost npx hardhat run scripts/sample-script.js --network localhost

That’s about it for this beginning exploration.

Thoughts: Wow okay so basically it allows me to spin up a network, deploy contracts through command line, write tests, and perform scripts. Everything that I need. Now I’ll just need to get into the details.