Transfer of Ethers between accounts

Introduction

In this section, we will guide you through the creation of an application that:

creates a transaction
signs it using the Ledger Nano then
sends it to the blockchain.

The purpose of the application is to transfer ethers from your ethereum account on your Ledger to another account.

Tutorial Prerequisites

Before starting, make sure you have gone through the prerequisites.

Receive Ether token in your Ledger Nano Ethereum Sepolia account

Create an Ethereum Sepolia account in Ledger Live
Send Sepolia Eth to your account with Infura faucet. You will need to create an account that will be useful later for the API key.

Fig. 1: Sepolia Ethereum Faucet

Tutorial implementation

In this implementation, we will be building a web application with vanilla javascript that uses the HID protocol from a Ledger package to communicate with the ledger.

Project Initialization

It is time to implement the application and test it. First, open a terminal and create a new folder. For this tutorial, the folder will be named “e2e-eth-tutorial”. Run:

mkdir e2e-eth-tutorial
cd e2e-eth-tutorial

Initialize the project by running the following:

npm init

Answer the questions displayed or by default press enter. There is no incidence on the execution.

Run:

touch index.html
touch index.js
touch style.css
mkdir assets

Copy the logo in the assets folder.

The folder will contain these files:

Folder tutorial Fig. 3: Folder of the Application

Code Implementation

index.html

In index.html copy-paste the following code :

<!DOCTYPE html>
<html>
  <head>
    <title>Parcel Sandbox</title>
    <meta charset="UTF-8" />
    <link rel="stylesheet" href="style.css">
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-1BmE4kWBq78iYhFldvKuhfTAU6auU8tT94WrHftjDbrCEXSU1oBoqyl2QvZ6jIW3" crossorigin="anonymous">
    <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/js/bootstrap.bundle.min.js" integrity="sha384-ka7Sk0Gln4gmtz2MlQnikT1wXgYsOg+OMhuP+IlRH9sENBO0LRn5q+8nbTov4+1p" crossorigin="anonymous"></script>
    <script src="https://cdn.jsdelivr.net/npm/web3@latest/dist/web3.min.js"></script>
    <script type="module" src="index.js"></script>
  </head>
 
  <body className="m-5">
    <div className="d-flex flex-column justify-content-center m-5 align-items-center">
      <p>Click on the bellow button to connect your Ledger Wallet</p>
      <button className="btn btn-primary w-25" data-bs-toggle="modal" data-bs-target="#WalletModal">Connect your Wallet</button>
    </div>
    <div className="d-flex flex-row">
      <div id="app" className="w-50">
        <form className="row g-3">
          <div className="col-md-12">
            <label for="wallet" className="form-label">Wallet Public Key</label>
            <input type="text" className="form-control" id="wallet" disabled>
          </div>
          <div className="col-md-12">
            <label for="recipient" className="form-label">Recipient</label>
            <input type="text" className="form-control" id="recipient">
          </div>
          <div className="col-md-6">
            <label for="gasPrice" className="form-label">Gas Price in wei</label>
            <input type="text" className="form-control" id="gasPrice" disabled>
          </div>
          <div className="col-md-6">
            <label for="gasLimit" className="form-label">Gas Limit in wei</label>
            <input type="text" className="form-control" id="gasLimit">
          </div>
          <div className="col-md-6">
            <label for="chainId" className="form-label">Chain ID</label>
            <input type="text" className="form-control" id="chainId" disabled>
          </div>
          <div className="col-md-6">
            <label for="value" className="form-label">Value</label>
            <input type="text" className="form-control" id="value" >
          </div>
          <div className="col-12">
            <button type="button" id="tx-transfer" className="btn btn-primary">Create Transaction</button>
          </div>
        </form>
      </div>
      <div className="w-50 d-flex flex-column">
            <p className="url">Ropsten etherscan: </p>
            <p  id="url"></p>
      </div>
    </div>
 
    <!-- Modal -->
    <div className="modal fade" id="WalletModal" tabindex="-1" aria-labelledby="WalletModalLabel" aria-hidden="true">
      <div className="modal-dialog">
        <div className="modal-content">
          <div className="modal-header">
            <h5 className="modal-title" id="WalletModalLabel">Choose your Wallet</h5>
            <button type="button" className="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
          </div>
          <div className="modal-body d-flex justify-content-center">
            <button id="connect-ledger" className="rounded-3 align-self-center" data-bs-dismiss="modal">
              <img src="./assets/ledger-logo.jpg" className="card-img-top" alt="Ledger">
            </button>
          </div>
        </div>
      </div>
    </div>
  </body>
</html>

index.js

In index.js copy-paste the following code and replace {YOUR_INFURA_APIKEY} by the API key you will find on your Infura account:

import { ethers } from "ethers";
import { InfuraProvider } from "ethers";
import TransportWebHID from "@ledgerhq/hw-transport-webhid";
import Eth from "@ledgerhq/hw-app-eth";
import ledgerService from "@ledgerhq/hw-app-eth/lib/services/ledger"
 
 
var ethers = require('ethers');
//Infuria provider for Sepolia network
const provider = new ethers.JsonRpcProvider("https://sepolia.infura.io/v3/{YOUR_INFURA_APIKEY}");
 
 
const chainId = 11155111; // Sepolia chainId
let gasPrice;
let addressWallet;
let recipient = "0x920f19c7F7Ce5b3170AdB94fDcC4570Da95D286b";
let value = 0.001;
let gasLimit = 1000000;
let nonce;
let _eth;
 
document.getElementById("connect-ledger").onclick = async function () {
 
    //Connecting to the Ledger Nano with HID protocol
    const transport = await TransportWebHID.create();
    
    //Getting an Ethereum instance and get the Ledger Nano ethereum account public key
    _eth = new Eth(transport);
    const { address } = await _eth.getAddress("44'/60'/0'/0/0", false);
 
    //Get some properties from provider
    addressWallet = address;
    gasPrice = (await provider.getFeeData()).gasPrice;
 
    //Fill the inputs with the default value
    document.getElementById("wallet").value = address;
    document.getElementById("gasPrice").value = ethers.formatUnits(gasPrice, 'wei');
    document.getElementById("chainId").value = chainId;
    document.getElementById("value").value = value;
    document.getElementById("recipient").value = recipient;
    document.getElementById("gasLimit").value = gasLimit;
}
 
 
document.getElementById("tx-transfer").onclick = async function () {
    //Getting information from the inputs
    addressWallet = document.getElementById("wallet").value;
    recipient =  document.getElementById("recipient").value;
    value =  document.getElementById("value").value;
    gasLimit =  parseInt(document.getElementById("gasLimit").value);
    nonce =  await provider.getTransactionCount(addressWallet, "latest");
 
    //Building transaction with the information gathered
    const transaction = {
        to: recipient,
        gasPrice: "0x" + parseInt(gasPrice).toString(16),
        gasLimit: ethers.toBeHex(gasLimit),
        nonce: nonce,
        chainId: chainId,
        data: "0x00",
        value: ethers.toBeHex(ethers.parseUnits(value, "ether")),
    }
 
    //Serializing the transaction to pass it to Ledger Nano for signing
    let unsignedTx = ethers.Transaction.from(transaction).unsignedSerialized.substring(2);
    const resolution = await ledgerService.resolveTransaction(unsignedTx, {}, {});
 
    //Sign with the Ledger Nano (Sign what you see)
    const signature = await _eth.signTransaction("44'/60'/0'/0/0",unsignedTx, resolution);
 
    //Serialize the same transaction as before, but adding the parsed signature on it
    let signedTx = ethers.Transaction.from({...transaction, 
        signature: {
        r: "0x"+signature.r,
        s: "0x"+signature.s,
        v: parseInt(signature.v),
        },
    }).serialized;
 
    //Sending the transaction to the blockchain
    const hash = (await provider.broadcastTransaction(signedTx)).hash;
 
    //Display the Sepolia etherscan on the screen
    const url = "https://sepolia.etherscan.io/tx/" + hash;
    document.getElementById("url").innerHTML = url;
}

style.css

In style.css copy-paste the following code :

.modal-content{
    width: 300px;
    height: 400px;
}
 
#connect-ledger{
    width: 17rem;
    height: 9rem;
    background-color: white;
    border: none;
}
 
#connect-ledger:hover{
    background-color: #EDEFF3;
}
 
.modal-body{
    background-color: #F7F9FD;
}
 
#url,.url{
    text-align: center;
    margin-top: 160px;
    color: green;
}

Dependencies Installation

Install the packages

Run:

npm install --save-dev parcel
npm install --save @ledgerhq/hw-app-eth
npm install --save @ledgerhq/hw-transport-webhid
npm install --save ethers

Package	What does it do?
parcel	It is a build tool that will help you package your application to run it in the browser.
@ledgerhq/hw-app-eth	It will help you ask your Ledger Nano to access the ethereum address.
@ledgerhq/hw-transport-webhid	It provides you with all the methods to interact with your Ledger with an HID connexion.
ethers	It provides you with all the methods to interact with the ethereum blockchain.

Modify Package.json

Modify the 5th line: "main": "index.js" => "source": "index.html" And ensure you have this line in scripts:

  "scripts": {
    "start": "parcel"
  },

Add this at the end of the script:

  "alias": {
    "@ledgerhq/devices": "@ledgerhq/devices/lib-es"
  }

Your file should now look like this:

{
    "name": "e2e-eth-tutorial",
    "version": "1.0.0",
    "description": "",
    "source": "index.html",
    "scripts": {
      "start": "parcel"
    },
    "author": "",
    "license": "ISC",
    "devDependencies": {
      "parcel": "^2.3.2"
    },
    "dependencies": {
      "@ledgerhq/hw-app-eth": "^6.26.0",
      "@ledgerhq/hw-transport-webhid": "^6.24.1",
      "ethers": "^5.5.4"
    },
    "alias": {
      "@ledgerhq/devices": "@ledgerhq/devices/lib-es"
    }
}

Tutorial Test

Start the Development Server

Now that the Setup is finished, the app has to be built to be displayed. Start the development server:

npm run start

Now the application is up and running. Open the browser and go to localhost:1234, it will display :

Fig. 5: Application Running on Browser

Plug Your Ledger Device

Before clicking on the text connect your Ledger to the USB port, unlock it and run the ethereum application. The steps are described below.

*Fig. 7: Run Ethereum Application on Ledger Nano*

*Fig. 8: Ethereum Application is Running on Ledger Nano*

Connect Your Ledger to the Application

Now you can click on the “Connect your Wallet” button and a modal will be opened. Click on the Ledger logo.

Fig. 9: Choice of Wallet

Now choose the Ledger Nano to connect it to the browser.

Fig. 10: Connect the Ledger Nano

If all goes well, the input fields will be filled with data. The greyed input is not to be changed and it is directly extracted either from the blockchain or from your Ledger Embedded application.

Fig. 11: Application After Connecting Ledger Nano

Create a transaction to transfer ethereum

Now that the inputs are filled with data. It is time to transfer some ether tokens from your Ledger ethereum account to another account (you can keep the default account on the “index.js” file).
Therefore, click on “Create Transaction” to create the transaction which will be signed by your ledger before sending it to the blockchain.

Fig. 12: Application After Connecting Ledger Nano

When the transaction proceed and finalize, an URL will be displayed on the screen. This URL is a link to Ropsten Etherscan to review the transaction.
There you can find all the information concerning the transaction you have previously sent.

Fig. 13: Result after Sending Transaction

If you go on Etherscan you can see the information of your transaction.

Result after Sending Transaction Fig. 14: Transaction Information on Sepolia Etherscan

Congratulations, you have successfully built your first transfer application connected with Ledger !!!

Info note Transfer of Sol between accounts