Account Abstraction for Web

Particle Network natively supports and facilitates end-to-end utilization of ERC-4337 account abstraction. This is primarily done through the account abstraction SDK, capable of constructing, sponsoring, and sending UserOperations, alongside deploying smart accounts, retrieving fee quotes, and other key functions. At the center of Particle Network’s Modular Smart Wallet-as-a-Service is the AA SDK, which fully supports web applications.

Repository

The Particle Network aa-sdk has an open-source GitHub repository providing full transparency of the underlying architecture. It may be worthwhile to look at this repository to contextualize the information below, making it easier to digest.


Getting Started

Configuring and initializing the Particle Network AA SDK is simple, although there are two key steps to consider beforehand: installing @particle-network/aa with either Yarn or npm and retrieving required core values from the Particle dashboard.

Installation

To begin with installation, you’ll need to choose either Yarn or npm, then run the command detailed below within your shell:

Terminal
yarn add @particle-network/aa

// Or

npm install @particle-network/aa

Setting up the Particle dashboard

You’ll also need required values from the Particle dashboard: your projectId, clientKey, and appId. Each of these values will be used in the initial configuration/initialization of the SDK and directly link your instance of the SDK with the Particle dashboard. Retrieving these values can be done by following the process below:

Follow the quickstart tutorial to set up a project and find the required keys: Create a new project.

Important details before initialization.

Before initializing the SDK, there are a few key points to keep in mind, specifically regarding the utilization of Paymasters (to sponsor gas fees, pay for gas in ERC-20 tokens, etc.)

- All Testnets automatically have the Verifying Particle Network Omnichain Paymaster enabled. Transactions that request it will automatically be sponsored and thus gasless.

- On the occasion that you’d like to use the Particle Network Omnichain Paymaster for Mainnets, you’ll need to deposit USDT on either Ethereum or BNB Chain within the Particle dashboard. This USDT will then automatically be converted as needed into the native token of the network you’re requesting (and qualifying for) sponsorship on.

- Alternatively, if you’d like to instead use Biconomy’s Verifying Paymaster, you can head over to the Biconomy dashboard, create a new Paymaster, and fill in paymasterApiKeys within aaOptions on SmartAccount.

- The Particle Network AA SDK automatically uses Biconomy’s Token Paymaster (for paying gas in ERC20 tokens). Transactions that request it will be able to leverage it without additional configuration.

Initialization

Initializing the Particle Network AA SDK is done primarily through the SmartAccount object, which can be imported directly from @particle-network/aa. A new instance of SmartAccount should be saved to a variable that’ll later be used either to construct a custom 1193 provider, or on its own to build and send User Operations.

Specifically, SmartAccount takes the following parameters:

  • provider, an 1193 provider to be called and used whenever specific functions are called (such as sendTransaction, signMessage, etc.); this can be new ParticleProvider(particle.auth) if you’re using Particle Auth, otherwise, this can be any typical 1193 provider.
  • Within the body of SmartAccount:
    • projectId, the projectId previously retrieved from the Particle dashboard.
    • clientKey, the clientKey previously retrieved from the Particle dashboard.
    • appId, the appId previously retrieved from the Particle dashboard.
    • aaOptions, an object containing the following:
      • accountContracts, an object dictating the smart account implementation(s) to be used. It can be:
    • paymasterApiKeys, an optional array (of objects) to be used when leveraging Biconomy’s Paymaster.
      • chainId, the chain ID being used by the Paymaster.
      • apiKey, the Biconomy Paymaster API key.

Once SmartAccount has been initialized and assigned, you can use that assignment (smartAccount in this case) to call setSmartAccountContract, reiterating/selecting the smart account implementation choice by passing an object containing name (BICONOMY, CYBERCONNECT, or SIMPLE), and version.

JavaScript
import { SmartAccount } from '@particle-network/aa';
  
const smartAccount = new SmartAccount(provider, {
    projectId: 'Particle Network project ID',
    clientKey: 'Particle Network client key',
    appId: 'Particle Network app ID',
    aaOptions: {
        accountContracts: {  // 'BICONOMY', 'CYBERCONNECT', 'SIMPLE', 'LIGHT', 'XTERIO'
            BICONOMY: [
                {
                    version: '1.0.0',  
                    chainIds: [x, xx],
                },
                {  
                    version: '2.0.0',
                    chainIds: [x, xx],
                }
            ],
            CYBERCONNECT: [
                {
                    version: '1.0.0',
                    chainIds: [x, xx], 
                }
            ],
            SIMPLE: [
                {
                    version: '1.0.0',
                    chainIds: [x, xx],
                }
            ],
        },
        paymasterApiKeys: [{ // Optional
            chainId: 1,  
            apiKey: 'Biconomy Paymaster API Key',
        }]
    }, 
});

smartAccount.setSmartAccountContract({ name: 'BICONOMY', version: '2.0.0' });

Examples of Utilization

Get Smart Account

Once you’ve initialized SmartAccount and connected your EOA (from Particle’s Wallet-as-a-Service or another wallet provider), you can retrieve the linked smart account address (according to the implementation chosen during initialization) with smartAccount.getAddress, the owner of that smart account (your EOA) with smartAccount.getOwner, and an object containing smart account information using smartAccount.getAccount. E.g.:

JavaScript
const address = await smartAccount.getAddress(); 
 
const address = await smartAccount.getOwner();

const accountInfo = await smartAccount.getAccount();

Get Fee Quotes

Before sending transactions, if you’d like to manually retrieve fee quotes for user-paid (in native tokens), gasless, and user-paid (in ERC-20 tokens) UserOperations, all with one method call, you can use smartAccount.getFeeQuotes, passing in either one standard transaction object or an array with multiple (if you’d like to batch transactions). This will return an object containing UserOperation objects (and hashes) for each of the three aforementioned fee payment mechanisms, alongside fee quotes for the token Paymaster, as shown below:

JavaScript
const tx = {  
    to: '0x...',
    value: '0x...'
}

const txs = [
    {
        to: '0x...',
        value: '0x...' 
    },
    {
        to: '0x...',
        value: '0x...'
    }  
]

const feeQuotesResult = await smartAccount.getFeeQuotes(tx);
  
const gaslessUserOp = feeQuotesResult.verifyingPaymasterGasless?.userOp;  
const gaslessUserOpHash = feeQuotesResult.verifyingPaymasterGasless?.userOpHash;
  
const paidNativeUserOp = feeQuotesResult.verifyingPaymasterNative?.userOp;   
const paidNativeUserOpHash = feeQuotesResult.verifyingPaymasterNative?.userOpHash;
  
const tokenPaymasterAddress = feeQuotesResult.tokenPaymaster.tokenPaymasterAddress;
const tokenFeeQuotes = feeQuotesResult.tokenPaymaster.feeQuotes;

Build UserOperation

To build a completed (ready for transaction) UserOperation object and corresponding hash, you can simply call smartAccount.buildUserOperation, passing in an object containing the following parameters:

  • tx, an object, or multiple objects (in an array) representing a standard transaction structure.
  • Optionally, feeQuote, which can be retrieved by getFeeQuotes, for utilizing a token Paymaster.
  • Optionally, tokenPaymasterAddress, the tokenPaymasterAddress property on a result from getFeeQuotes.
JavaScript
const userOpBundle = await smartAccount.buildUserOperation({ tx, feeQuote, tokenPaymasterAddress }) 
const userOp = userOpBundle.userOp;  
const userOpHash = userOpBundle.userOpHash;

Send UserOperation

You can send and push an (already built and complete) UserOperation to the network with smartAccount.sendUserOperation, which takes an object containing a userOp object and corresponding userOpHash. Both of these can be retrieved from passing a structured transaction into buildUserOperation, as was covered above. E.g.:

JavaScript
const txHash = await smartAccount.sendUserOperation({ userOp, userOpHash });  

Wallet Deployment Flow

An undeployed smart account will automatically be deployed upon the first transaction (UserOperation) it sends through the SDK (the deployment transaction is bundled/batched with the other chosen transaction). If you’d like to initiate deployment manually, bypassing automatic deployment, then you can use smartAccount.deployWalletContract, which will create, request signature for, and send a deployment transaction. The status of deployment can be retrieved with smartAccount.isDeployed. E.g.:

JavaScript
const isDeploy = await smartAccount.isDeployed(); 
if (!isDeploy) {
    const txHash = await smartAccount.deployWalletContract();
}

Custom 1193 AA Provider

Alternatively, if you’d like to plug the Particle Network AA SDK directly into Ethers or web3.js, you can do so by creating a custom 1193 provider; this will automatically route transactions through the provider and configuration defined within SmartAccount, converting typical transactions with Ethers, web3.js, and viem into UserOperations, handling everything on the backend.

This can be achieved by creating a new instance of AAWrapProvider, imported from @particle-network/aa. AAWrapProvider takes two parameters:

  • SmartAccount, an instance of SmartAccount.
  • SendTransactionMode, optionally defining the mechanism to be used for paying gas fees.
    • SendTransactionMode can be imported from @particle-network/aa, and includes:
      • SendTransactionMode.UserPaidNative, traditional gas payments.
      • SendTransactionMode.Gasless, sponsored. This will happen automatically for Testnets, and will pull from your previously defined (or configured) Paymaster for Mainnets.
      • SendTransactionMode.UserSelect, lets the user select which mechanism they’d like to use, including ERC-20 payments.

E.g.:

JavaScript
import { AAWrapProvider, SendTransactionMode, SendTransactionEvent } from '@particle-network/aa';
import Web3 from "web3";

const wrapProvider = new AAWrapProvider(smartAccount, SendTransactionMode.UserPaidNative);  
const web3 = new Web3(wrapProvider);  

await web3.eth.sendTransaction(tx);
  
  
const wrapProvider = new AAWrapProvider(smartAccount, SendTransactionMode.Gasless);
const web3 = new Web3(wrapProvider);
await web3.eth.sendTransaction(tx);


const wrapProvider = new AAWrapProvider(smartAccount, SendTransactionMode.UserSelect);
const web3 = new Web3(wrapProvider);
wrapProvider.once(SendTransactionEvent.Request, (feeQuotesResult) => {  
    wrapProvider.resolveSendTransaction({
        feeQuote: feeQuotesResult.tokenPaymaster.feeQuote[0],  
        tokenPaymasterAddress: feeQuotesResult.tokenPaymaster.tokenPaymasterAddress
    });

    wrapProvider.resolveSendTransaction(feeQuotesResult.verifyingPaymasterNative);
    
    if (feeQuotesResult.verifyingPaymasterGasless) {
        wrapProvider.resolveSendTransaction(feeQuotesResult.verifyingPaymasterGasless); 
    }   
});
await web3.eth.sendTransaction(tx);

Master reference

For a direct, raw view into every method provided through SmartAccount, below is a table containing every relevant one alongside specific parameters and a short description. For methods listed that weren’t covered in the above examples, live implementation often mimics the common structure covered throughout this document.

ClassMethodsParameters (* indicates optional)
SmartAccountconstructorprovider, config
SmartAccountsetSmartAccountContractcontract
SmartAccountgetChainId
SmartAccountgetAccountConfig
SmartAccountgetPaymasterApiKey
SmartAccountgetFeeQuotestx
SmartAccountbuildUserOperationtx, feeQuote, tokenPaymasterAddress
SmartAccountsignUserOperationuserOpHash, userOp
SmartAccountsendUserOperationuserOpHash, userOp
SmartAccountsendSignedUserOperationuserOp, sessionDataParams*
SmartAccountsendTransactiontx, feeQuote, tokenPaymasterAddress
SmartAccountgetAccount
SmartAccountgetAddress
SmartAccountgetOwner
SmartAccountisDeployed
SmartAccountdeployWalletContract
SmartAccountsendRpcarg
SmartAccountcreateSessionsoptions
SmartAccountvalidateSessiontargetSession, sessions