Hardhat Simple Storage

This is a section of the Javascript Blockchain/Smart Contract FreeCodeCamp Course.

⌨️ (08:20:17) Lesson 6: Hardhat Simple Storage

This repo has been updated for Sepolia over Goerli.

Full Repo

This project is apart of the Hardhat FreeCodeCamp video.

Getting Started

Requirements

  • git
    • You'll know you did it right if you can run git --version and you see a response like git version x.x.x
  • Nodejs
    • You'll know you've installed nodejs right if you can run:
      • node --version and get an output like: vx.x.x
  • Yarn instead of npm
    • You'll know you've installed yarn right if you can run:
      • yarn --version and get an output like: x.x.x
      • You might need to install it with npm or corepack

Quickstart

git clone https://github.com/PatrickAlphaC/hardhat-simple-storage-fcc
cd hardhat-simple-storage-fcc
yarn
yarn hardhat

Typescript

For the typescript edition, run:

git checkout typescript

Optional Gitpod

If you can't or don't want to run and install locally, you can work with this repo in Gitpod. If you do this, you can skip the clone this repo part.

Open in Gitpod

Usage

Deploy:

npx hardhat run scripts/deploy.js

Testing

npx hardhat test

Test Coverage

npx hardhat coverage

Estimate gas

You can estimate how much gas things cost by running:

npx hardhat test

And you'll see and output file called gas-report.txt

Local Deployment

If you'd like to run your own local hardhat network, you can run:

npx hardhat node

And then in a different terminal

npx hardhat run scripts/deploy.js --network localhost

And you should see transactions happen in your terminal that is running npx hardhat node

Important localhost note

If you use metamask with a local network, everytime you shut down your node, you'll need to reset your account. Settings -> Advanced -> Reset account. Don't do this with a metamask you have real funds in. And maybe don't do this if you're a little confused by this.

Deployment to a testnet or mainnet

  1. Setup environment variables

You'll want to set your SEPOLIA_RPC_URL and PRIVATE_KEY as environment variables. You can add them to a .env file, similar to what you see in .env.example.

  • PRIVATE_KEY: The private key of your account (like from metamask). NOTE: FOR DEVELOPMENT, PLEASE USE A KEY THAT DOESN'T HAVE ANY REAL FUNDS ASSOCIATED WITH IT.
  • SEPOLIA_RPC_URL: This is url of the sepolia testnet node you're working with. You can get setup with one for free from Alchemy
  1. Get testnet ETH

Head over to faucets.chain.link and get some tesnet ETH. You should see the ETH show up in your metamask.

  1. Deploy
npx hardhat run scripts/deploy.js --network sepolia

Verify on etherscan

If you deploy to a testnet or mainnet, you can verify it if you get an API Key from Etherscan and set it as an environment variable named ETHERSCAN_API_KEY. You can pop it into your .env file as seen in the .env.example.

In it's current state, if you have your api key set, it will auto verify sepolia contracts!

However, you can manual verify with:

npx hardhat verify --constructor-args arguments.js DEPLOYED_CONTRACT_ADDRESS

Linting

To check linting / code formatting:

yarn lint

or, to fix:

yarn lint:fix

Thank you!

If you appreciated this, feel free to follow me or donate!

ETH/Polygon/Avalanche/etc Address: 0x9680201d9c93d65a3603d2088d125e955c73BD65

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