Using Account abstraction in Typescript

Deployable via the explore page or build your own ERC 4337 compatible factory contract using the Solidity SDK. hirdweb offers the following three different kinds of account factories:

Read about the differences between the three factory types here.

To use the bundler and paymaster, you must create an API key and a billing account.

To create an API Key:

• Head to the settings page in the dashboard and click the API Keys tab.
• Click on Create API Key:
• Follow the steps to create your API key.

To use account abstraction infrastructure on mainnet you will also need to create an account and add a payment method.

To use smart accounts in a node script, we are going to setup our project using the CLI create command. Open your terminal and run:

npx thirdweb create app

When promted, select/input the following options:

• A name for the project
• EVM as the blockchain
• Node.js as the environment
• TypeScript as the language

This will create a repository. Open it in your code editor.

Create a .env file and add the following:

THIRDWEB_SECRET_KEY=<YOUR_SECRET_KEY>

Open the index.ts file and delete the starter script, we won't need it.

This smart account is unlocked by a 'key' - a personal wallet. This key can be anything from a MetaMask wallet or even a Local Wallet and is used as a way to 'sign in' to the wallet.

First install the wallets package if you haven't already:

yarn add @thirdweb-dev/wallets

To create a personal wallet key, we are going to use the Local Wallet, which we need to import from the @thirdweb-dev/wallets package, and store it in an ecrypted JSON file.

import { LocalWalletNode } from "@thirdweb-dev/wallets/evm/wallets/local-wallet-node";
 
// Load or create personal wallet
// here we generate LocalWallet that will be stored in wallet.json
const personalWallet = new LocalWalletNode();
await personalWallet.loadOrCreate({
  strategy: "encryptedJson",
  password: "my_password", // or any password
});
const personalWalletAddress = await personalWallet.getAddress();
console.log("Personal wallet address:", personalWalletAddress);

Now, let's create a smart account using the SmartWallet class from the @thirdweb-dev/wallets package. To do this, we need to pass a SmartWalletConfig object to the constructor. This object contains the following properties:

• chain: the chain that the smart account will be deployed on.
• factoryAddress: the address of the account factory contract.
• secretKey: the secret key that we created earlier.
• gasless: whether the smart account should have sponsored transactions or not.

Once we have created the config and instantiating the SmartWallet class, we can connect the personal wallet to the smart account using the connect method.

// Configure the smart wallet
const config: SmartWalletConfig = {
  chain: "goerli",
  factoryAddress: "0x...", // your factory address
  secretKey: process.env.THIRDWEB_SECRET_KEY as string,
  gasless: true,
};
 
// Connect the smart wallet
const smartWallet = new SmartWallet(config);
await smartWallet.connect({
  personalWallet,
});

To view all of the methods on the SmartWallet class, view the Wallet SDK documentation.

Now that we have created a smart account object and connected it, we can instantiate the thirdweb SDK with the smart account using the fromWallet method.

// now use the SDK normally to perform transactions with the smart wallet
const sdk = await ThirdwebSDK.fromWallet(smartWallet, chain, {
  secretKey: secretKey,
});
 
console.log("Smart Account addr:", await sdk.wallet.getAddress());
console.log("balance:", (await sdk.wallet.balance()).displayValue);

We have also passed our secretKey to the SDK so that we can use the bundler and paymaster.

We have also added some helpful logs to view the smart account address and balance using the associated balance and getAddress methods.

In order to follow this specific example, you will need the following setup:

• Deploy a token drop contract deployed on Goerli.
• Claim conditions set so that tokens can be claimed

Now let's use this smart account to claim an ERC20 token from a token drop contract!

First, we will get the contract instance of an ERC20 token drop contract using the getContract method. Then, we will get the balance of the ERC20 token using the balance method and log it to the console. Finally, we will claim 1 ERC20 token using the claim method and log the transaction hash to the console.

// Claim a ERC20 token
const contract = await sdk.getContract(
  "0xc54414e0E2DBE7E9565B75EFdC495c7eD12D3823", // TokenDrop on goerli
);
const tokenBalance = await contract.erc20.balance();
console.log("ERC20 token balance:", tokenBalance.displayValue);
const tx = await contract.erc20.claim(1);
console.log(
  "Claimed 1 ERC20 token, tx hash:",
  tx.receipt.transactionHash,
);

To run the script, run the following command:

yarn dev

As you can see in the terminal output, upon claiming the token, the smart account is deployed. This is because smart account contracts are deployed when the first transaction is initiated.

We have successfully deployed a smart account using our factory contract and claimed an ERC20 token!

In this guide, we have learnt how to use the wallet SDK with the TypeScript SDK to create a smart account and claim an ERC20 token.

Take a look at the GitHub Repository for the full source code!