Dapp University Bootcamp - Token Exchange

This project is a blockchain-based token exchange application built during the Dapp University Bootcamp. Demonstrating how to create, deploy, and interact with Ethereum smart contracts.

Project Overview

This application includes:

• A custom ERC-20 token smart contract (DAPPU)
• Smart contract testing with Hardhat
• React frontend for interacting with the blockchain
• Integration with MetaMask for wallet connectivity

Prerequisites

Before getting started, make sure you have:

• Node.js (v14+ recommended)
• npm (comes with Node.js)
• MetaMask browser extension
• Basic knowledge of JavaScript, React, and blockchain concepts

Installation

1. Clone this repository

2. Install dependencies:

   To check if node is installed: node -v

   If not installed: curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.3/install.sh | bash

   Run: nvm -v

   If not installed:

   Since macOS 10.15, the default shell is zsh and nvm will look for .zshrc to update, none is installed by default. Create one with touch ~/.zshrc and run the install script again. Rerun: curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.3/install.sh | bash

   Use nvm to install the latest LTS release of Node.js nvm install --lts

   To install a specific version: nvm install x.xx.x ex: nvm install 8.16.2

   Example to set the default version of node to use when starting a new shell to 10.0.0: nvm alias default 10.0.0 > nvm alias 20.10

   To see the entire list of Node.js versions available to install, enter the following: nvm ls-remote

   To select a version: nvm use xx >ex=: nvm use 22

   To upgrade npm to the latest version:npm install npm --global

3. Create a .env file in the root directory with your private keys and API keys:

   PRIVATE_KEYS=your_private_key
   ALCHEMY_API_KEY=your_alchemy_api_key
   ETHERSCAN_API_KEY=your_etherscan_api_key
   

Blockchain Development

To start new project:

Hardhat:

• mkdir 'hardhat_example'

• cd 'hardhat_example'

• npm init --yes creates 'package.json'

• npm install --sav-dev hardhat

• npx hardhat to create new project

  select "no" to installing dependencies

  if selected "yes" , delete 'package-lock.json' & 'node_modules' directories

• Change package.json to reflect the following:

  {
     "name": "hardhat_example",
     "version": "1.0.0",
     "description": "",
     "main": "index.js",
     "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1"
     },
     "keywords": [],
     "author": "",
     "license": "ISC",
     "devDependencies": {
     "@nomiclabs/hardhat-ethers": "^2.0.6",
     "@nomiclabs/hardhat-waffle": "^2.0.3",
     "chai": "^4.3.6",
     "ethereum-waffle": "^3.4.4",
     "ethers": "^5.6.8",
     "hardhat": "^2.9.7"
     }
  }
  

• After updating 'package.json' , rerun: npm install

• Adjust hardhat.config.js to reflect the following:

  Added require("@nomiclabs/hardhat-waffle");

  /** @type import('hardhat/config').HardhatUserConfig */
  module.exports = {
     solidity: "0.8.19",
     networks: {
     localhost: {}
     },
  };
  

  changing line 1: require("@nomicfoundation/hardhat-toolbox"); to "@nomiclabs/hardhat-waffle"

Compile Smart Contracts

To create ABI - json description of smart contract & byte code - human readable code --> machine code for EVM

npx hardhat compile

Run Tests

npx hardhat test

Deploy to Local Network

npx hardhat node
npx hardhat run scripts/1_deploy.js --network localhost

or

npx hardhat run --network localhost ./scripts/1_deploy.js

Deploy to Sepolia Testnet

npx hardhat run scripts/1_deploy.js --network sepolia

Verify Contract on Etherscan

npx hardhat verify --network sepolia <contract address> <constructor args>

Ex: > npx hardhat verify --network sepolia “Dapp University” “DAPPU” “1000000”

Getting Started with Create React App

This project was bootstrapped with Create React App. To create react app:

npx create-react-app blockchain-developer-bootcamp --use-npm

  Modify app.js file in "src" directory to see reflected changes

Available Scripts

In the project directory, you can run:

npm start

Runs the app in the development mode.
Open http://localhost:3000 to view it in your browser.

The page will reload when you make changes.
You may also see any lint errors in the console.

npm test

Launches the test runner in the interactive watch mode.
See the section about running tests for more information.

npm run build

Builds the app for production to the build folder.
It correctly bundles React in production mode and optimizes the build for the best performance.

The build is minified and the filenames include the hashes.
Your app is ready to be deployed!

See the section about deployment for more information.

npm run eject

Note: this is a one-way operation. Once you eject, you can't go back!

If you aren't satisfied with the build tool and configuration choices, you can eject at any time. This command will remove the single build dependency from your project.

Instead, it will copy all the configuration files and the transitive dependencies (webpack, Babel, ESLint, etc) right into your project so you have full control over them. All of the commands except eject will still work, but they will point to the copied scripts so you can tweak them. At this point you're on your own.

You don't have to ever use eject. The curated feature set is suitable for small and middle deployments, and you shouldn't feel obligated to use this feature. However we understand that this tool wouldn't be useful if you couldn't customize it when you are ready for it.

Learn More

You can learn more in the Create React App documentation.

To learn React, check out the React documentation.

Code Splitting

This section has moved here: https://facebook.github.io/create-react-app/docs/code-splitting

Analyzing the Bundle Size

This section has moved here: https://facebook.github.io/create-react-app/docs/analyzing-the-bundle-size

Making a Progressive Web App

This section has moved here: https://facebook.github.io/create-react-app/docs/making-a-progressive-web-app

Advanced Configuration

This section has moved here: https://facebook.github.io/create-react-app/docs/advanced-configuration

Deployment

This section has moved here: https://facebook.github.io/create-react-app/docs/deployment

npm run build fails to minify

This section has moved here: https://facebook.github.io/create-react-app/docs/troubleshooting#npm-run-build-fails-to-minify

blockchain-developer-bootcamp

• /: Test to make ensure VScode UI source control working again after ggshield pre-commit "command not found"