Ethereum

Setting up a Local Ethereum Network with Hardhat

This README guides you through setting up a local Ethereum network using Hardhat, deploying an ERC20 token, and performing token and ETH transfers.

Table of Contents

1. Prerequisites

2. Installation

3. Project Structure

4. Setting Up the Local Network

5. Deploying the ERC20 Token

6. Performing ERC20 Token Transfers

7. Performing ETH Transfers

8. Troubleshooting

Prerequisites

• Node.js (v12.0.0 or later)

• npm (usually comes with Node.js)

Installation

1. Clone the wallet-test-tools repo

git clone https://github.com/tetherto/wallet-lib-test-tools
cd wallet-lib-test-tools

Install the dependencies

npm install

1. Navigate to the eth directory and install the dependencies:

cd src/eth
npm install

Project Structure

.
├── contracts/
│   └── YourERC20Token.sol
├── scripts/
│   ├── deployer.js
│   ├── erc-transfer.js
│   └── eth-transfer.js
├── hardhat.config.js
├── index.js
└── README.md

Setting Up the Local Network

To start your local Ethereum network:

For more detailed information, refer to the Hardhat documentation.

npx hardhat node

This command will start a local Ethereum network and display a list of available accounts with their private keys.

Keep this terminal window open while working with your local network.

IMPORTANT: closing this process will reset your blockchain, you would need to redo any transactions you may have done

Deploying the ERC20 Token

To deploy your ERC20 token to the local network:

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

This script will deploy your ERC20 token and output the contract address. Make note of this address for future use.

Performing ERC20 Token Transfers

To transfer ERC20 tokens:

ADDR=<recipient-address> AMT=<amount> npx hardhat run ./scripts/erc-transfer.js --network localhost

Replace <recipient-address> with the Ethereum address you want to send tokens to, and <amount> with the number of tokens to send.

Example:

ADDR=0x6122cfcd13692dfbe876e513109c5b653c4c2399 AMT=1222 npx hardhat run ./scripts/erc-transfer.js --network localhost

Performing ETH Transfers

To transfer ETH:

ADDR=<recipient-address> AMT=<amount> npx hardhat run ./scripts/eth-transfer.js --network localhost

Replace <recipient-address> with the Ethereum address you want to send ETH to, and <amount> with the amount of ETH to send.

Example:

ADDR=0x6122cfcd13692dfbe876e513109c5b653c4c2399 AMT=1 npx hardhat run ./scripts/eth-transfer.js --network localhost

🧪 EthTester Class

A utility class for testing Ethereum transactions and smart contracts, designed to work with local Ethereum networks like Hardhat.

📚 Table of Contents

• Usage
• API
• Configuration
• Dependencies
• Contributing
• License

🔧 Usage

Here's a quick example of how to use EthTester:

const EthTester = require('eth-tester');

async function example() {
  const tester = new EthTester({
    uri: 'http://localhost:8545',
    privateKey: '0xYourPrivateKey'
  });

  await tester.init();

  // Mine a block
  await tester.mine();

  // Send Ether to an address
  await tester.sendToAddress({
    address: '0xRecipientAddress',
    amount: '1'  // 1 ETH
  });

  // Send tokens to an address
  await tester.sendToken({
    address: '0xRecipientAddress',
    amount: '1000000000000000000'  // 1 token (assuming 18 decimals)
  });
}

example();

📘 API

EthTester

Constructor

• new EthTester(config)

  • config.uri: (optional) The Ethereum node URI (default: 'http://127.0.0.1:8545/')

  • config.privateKey: (optional) The private key to use for transactions

Methods

• init()

  • Initializes the connection to the Ethereum network

• mine(opts)

  • Mines new blocks

  • opts.blocks: (optional) Number of blocks to mine (default: 1)

• sendToAddress(opts)

  • Sends Ether to an address

  • opts.address: Recipient's Ethereum address

  • opts.amount: Amount of Ether to send

• sendToken(opts)

  • Sends ERC20 tokens to an address

  • opts.address: Recipient's Ethereum address

  • opts.amount: Amount of tokens to send

• getNewAddress()

  • Returns the Ethereum address associated with the configured private key

⚙️ Configuration

EthTester uses a configuration file erc20.config.json for ERC20 token details. Ensure this file is present in the same directory with the following structure:

{
  "contractAddress": "0xYourTokenContractAddress"
}