Ethers.js – How to Change Default Wallet Address in Ethers.js

ethers.js

I am trying to change the default address used by the wallet to send transactions.

let wallet = Wallet.fromMnemonic('hurdle cloud ...').connect(provider);

wallet.address // 0xfB98c...

How do I change the wallet's address to another address from the same private key? I feel like this should be obvious but digging through the documentation it doesn't appear possible.

Edit

Given that a single private key only has a single public key (and public address), the question needs adjusting. How would it be possible to generate new private keys (and therefore public addresses) from this mnemonic using ethers.js?

Best Answer

You can use an HDNode which is defined as:

A Hierarchical Deterministic Wallet represents a large tree of private keys which can reliably be reproduced from an initial seed. Each node in the tree is represented by an HDNode which can be descended into.

When you use this HDNode, you can change the path variable you give it in order to get different private/public key pairs that are derived from this HDNode.

You can learn more about the path variable here. For Ethereum wallets, the default address / private key used is at path: m/44'/60'/0'/0/0. To follow the outlined protocol, for ethereum addresses, you can change the account and/or index fields: m/44'/60'/1'/0/0 m/44'/60'/0'/0/1

let HDNode = require('ethers').utils.HDNode;

let mnemonic = "radar blur cabbage chef fix engine embark joy scheme fiction master release";

let masterNode = HDNode.fromMnemonic(mnemonic);

let standardEthereum = masterNode.derivePath("m/44'/60'/0'/0/0");

console.log(standardEthereum.publicKey);
console.log(standardEthereum.privateKey);

//account 0 index 1
let accountZeroIndexOne = masterNode.derivePath("m/44'/60'/0'/0/1");
console.log(accountZeroIndexOne.publicKey);
console.log(accountZeroIndexOne.privateKey);

Related Solutions

Ethers.js – Handling GetAmountsOut Returning [object Promise]

In case this is still unanswered, you can do the following:

// ... previous code
const amountIn = ethers.utils.parseUnits('0.1', 'ether');

// put the asynchronous stuff and it's dependent code inside an IIFE
(async() => {
  const amountsOut = router.getAmountsOut(amountIn, [tokenIn, tokenOut]);
  console.log(`
    tokenOut: ${amountsOut.toString()}
`);
})();

Web3.js – Encrypting and Decrypting Data on IPFS Using Ethereum Keys

You'll need to the encrypt the data before storing on IPFS. But its not efficient to use ECIES encryption (which uses Ethrereum keys) on large data as its slow and Metamask will often hang. A good strategy would be to encrypt the data using a symmetric encryption like AES256. You can use something like CryptoJs for the same. Then you can encrypt the AES256 key using the Public Key of the recipient's Ethrereum address.

To get Public Key from Metamask, you can request it via eth_getEncryptionPublicKey (docs). Or if the recipient has at least one transaction on Ethrereum, you can recover public key from the transaction data like this.

Now that you have the recipient's public key, you encrypt the AES256 key with it using ECIES encryption. Now you can add both the encrypted data (encrypted using AES256) and the encrypted AES256 key (encrypted using ECIES) to IPFS. You can do this using various ways, like creating a text file of the encrypted key and zipping it along with the encrypted data so you get a single file. Or add it as separate files, or create a directory.

To get the data, the recipient will have to download both the data and encrypted AES256 key from IPFS. Then decrypt the encrypted AES256 key using their public key. You can do this using Metamask using eth_decrypt(docs). Now with the AES256 key, you can decrypt the data.

You can checkout this project which implemented this idea. Hope this helps :)

Best Answer

Related Solutions

Ethers.js – Handling GetAmountsOut Returning [object Promise]

Web3.js – Encrypting and Decrypting Data on IPFS Using Ethereum Keys

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