Using Smart Wallets

To request signatures or transactions from a connected wallet, you can either:

Use the wallet's EIP-1193 provider to send JSON-RPC requests to the wallet directly.
Pass the wallet to a library like viem, ethers, or wagmi.
For the embedded wallet specifically, create a transactionIntent from the server and signMessage it with the embedded wallet (client).

Signatures

Choose your preferred approach for handling wallet signatures:

Signing Messages with EIP-1193 Provider

The request method of the EIP-1193 provider can be used to request signatures. First, get the provider:

client.tsx

import openfort from "./openfortConfig"
// This example assumes you have already checked that Openfort 'embeddedState' is 
// `ready` and the user is `authenticated`
const provider = openfort.embeddedWallet.getEthereumProvider();

openfortConfig.ts

import Openfort from '@openfort/openfort-js';
 
const openfort = new Openfort({
  baseConfiguration: {
    publishableKey: "YOUR_OPENFORT_PUBLISHABLE_KEY",
  },
  shieldConfiguration: {
    shieldPublishableKey: "YOUR_SHIELD_PUBLISHABLE_KEY",
  },
});
 
export default openfort;

Then use the provider's request method with eth_sign or related methods:

const message = "Sign this message";
const signature = await provider.request({
  method: 'personal_sign',
  params: [message, address]
});

Signing Typed Data with EIP-1193 Provider

The request method of the EIP-1193 provider can be used to sign typed data. First, get the provider:

client.tsx

import openfort from "./openfortConfig"
// This example assumes you have already checked that Openfort 'embeddedState' is 
// `ready` and the user is `authenticated`
const provider = openfort.embeddedWallet.getEthereumProvider();

Then use the provider's request method with eth_signTypedData_v4:

const address = "0x0000000000000000000000000000000000000000";
 
const domain = {
  name: "Ether Mail",
  version: "1",
  chainId: 1,
  verifyingContract: "0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC",
};
 
const types = {
  EIP712Domain: [
    { name: "name", type: "string" },
    { name: "version", type: "string" },
    { name: "chainId", type: "uint256" },
    { name: "verifyingContract", type: "address" },
  ],
  Person: [
    { name: "name", type: "string" },
    { name: "wallet", type: "address" },
  ],
  Mail: [
    { name: "from", type: "Person" },
    { name: "to", type: "Person" },
    { name: "contents", type: "string" },
  ],
};
 
const message = {
  from: { name: "Cow", wallet: "0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826" },
  to: { name: "Bob", wallet: "0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB" },
  contents: "Hello, Bob!",
};
 
const signature = await provider.request({ method: "eth_signTypedData_v4",
  params: [address, JSON.stringify({ domain, types, primaryType: "Mail", message })],
});

Integration with Web3 Libraries

If you've integrated Openfort with another library, you can also use that library's syntax for requesting signatures:

Library	Method
Ethers	Use the signer's `signMessage` method
Wagmi	Use the `useSignMessage` hook
Viem	Use the `signMessage` action

For typed data:

Library	Method
Ethers	Use the signer's `_signTypedData` method
Wagmi	Use the `useSignTypedData` hook
Viem	Use the `signTypedData` action

Signing Messages with Openfort SDK

To request a signature from a user, use the signMessage method.

When invoked, signMessage will request an EIP-191 personal_sign signature from the embedded wallet, and returns a Promise for the user's signature as a string.

client.tsx

import openfort from "./openfortConfig"
 
// This example assumes you have already checked that Openfort 'embeddedState' is 
// `ready` and the user is `authenticated`
async function signMessageButton(message:string) {
  await openfort.embeddedWallet.signMessage(message);
}

openfortConfig.ts

import Openfort from '@openfort/openfort-js';
 
const openfort = new Openfort({
  baseConfiguration: {
    publishableKey: "YOUR_OPENFORT_PUBLISHABLE_KEY",
  },
  shieldConfiguration: {
    shieldPublishableKey: "YOUR_SHIELD_PUBLISHABLE_KEY",
  },
});
 
export default openfort;

Signing Typed Data with Openfort SDK

To have a user sign an EIP-712 typed data signature, use the signTypedData method.

When invoked, signTypedData will request an EIP-721 eth_signTypedData_v4 signature from the embedded wallet, and returns a Promise for the user's signature as a string.

client.tsx

import openfort from "./openfortConfig"
 
// This example assumes you have already checked that Openfort 'embeddedState' is 
// `ready` and the user is `authenticated`
async function signTypedMessageButton(domain: any, types: any, value: any) {
  await openfort.embeddedWallet.signTypedData(domain, types, value);
}

Transactions

Choose your preferred approach for handling wallet transactions:

Native Transactions with EIP-1193 Provider

Get the provider and optionally configure gas policy to make a sponsored transaction:

client.tsx

import openfort from "./openfortConfig"
// This example assumes you have already checked that Openfort 'embeddedState' is 
// `ready` and the user is `authenticated`
const provider = await openfort.embeddedWallet.getEthereumProvider({
      policy: 'pol_...',
    });

openfortConfig.ts

import Openfort from '@openfort/openfort-js';
 
const openfort = new Openfort({
  baseConfiguration: {
    publishableKey: "YOUR_OPENFORT_PUBLISHABLE_KEY",
  },
  shieldConfiguration: {
    shieldPublishableKey: "YOUR_SHIELD_PUBLISHABLE_KEY",
  },
});
 
export default openfort;

Then, using the provider's request method, send a eth_sendTransaction JSON-RPC to the wallet:

const transactionRequest = {
  to: '0xRecipientAddress',
  value: 100000,
};
const txHash = await provider.request({
  method: 'eth_sendTransaction',
  params: [transactionRequest],
});

Smart Contract Interactions with EIP-1193 Provider

Calling a smart contract is a special case of sending a transaction. To call a smart contract, you should send a transaction with the following parameters:

to: the address of the smart contract to call
data: the encoded function call data
value: any value to send (for payable functions)

To prepare the calldata for a smart contract interaction, we recommend using viem's encodeFunctionData method:

import { encodeFunctionData } from 'viem';
 
const data = encodeFunctionData({
  abi: contractAbi,
  functionName: 'methodName',
  args: [arg1, arg2]
});

You can then send a transaction from the wallet as normal, and pass the calldata in the data field:

const transactionRequest = {
  to: '0xTheContractAddress',
  data: data,
  value: 100000, // Only necessary for payable methods
};
const txHash = await provider.request({
  method: 'eth_sendTransaction',
  params: [transactionRequest]
});

Batched Transactions with EIP-1193 Provider

Smart wallets support sending a batch of transactions in a single, atomic submission to the network.

To send batched transactions with a smart wallet, call the wallet_sendCalls method with a calls array of the transactions to batch together:

const txHash = await provider.request({
  method: 'wallet_sendCalls',
  params: [
    {
      calls: [
        // Approve transaction
        {
          to: USDC_ADDRESS,
          data: encodeFunctionData({
            abi: USDC_ABI,
            functionName: 'approve',
            args: ['insert-spender-address', BigInt(1e6)],
          }),
        },
        // Transfer transaction
        {
          to: USDC_ADDRESS,
          data: encodeFunctionData({
            abi: USDC_ABI,
            functionName: 'transfer',
            args: ['insert-recipient-address', BigInt(1e6)],
          }),
        },
      ],
    },
  ],
});

Integration with Wallet Libraries

If you've integrated Openfort with another library, you can also use that library's syntax for sending transactions:

Library	Method
Ethers	Use the signer's `sendTransaction` method.
Wagmi	Use the `useSendTransaction` hook.
Viem	`sendTransaction` action

For batched transactions:

Library	Method
Wagmi	Use the `useWriteContracts` hook.
Viem	`sendCalls` action

Transaction Flow with Openfort SDK

The Openfort SDK uses a two-step approach: create the transaction intent on the server, then sign it on the client.

1. Create Transaction Intent on Server

Create a request to your backend to create a transaction. In the body of the request:

Include the player that signs the transaction.
Include the policy that interacts with the contract for gas. If non-existent the user will need to have gas tokens.
Include optimistic if you want the transactions to be confirmed faster.

Native Token Transfer

Send the value of native tokens in the smallest denomination of the native currency i.e. wei (10^18) and as a string.

Curl

curl https://api.openfort.io/v1/transaction_intents \
  -H "Authorization: Bearer $YOUR_SECRET_KEY" \
  -d player="pla_..." \
  -d policy="pol_..." \
  -d chainId=80002 \
  -d optimistic=true \
  -d "interactions[0][value]=1000" \
  -d "interactions[0][to]=pla_..."

For a useful resource for computing the Wei, you can visit the wei calculator.

Smart Contract Transactions

curl

curl https://api.openfort.io/v1/transaction_intents \
  -H "Authorization: Bearer $YOUR_SECRET_KEY" \
  -d player="pla_..." \
  -d policy="pol_..." \
  -d chainId=80002 \
  -d optimistic=true \
  -d "interactions[0][contract]"="con_..." \
  -d "interactions[0][functionName]"="mint" \
  -d "interactions[0][functionArgs][0]"="0x63B7...484f"

Batching Transactions

Smart accounts support batching transactions, allowing multiple actions to be rolled into one. This feature significantly simplifies Web3 interactions for your users. For example, instead of executing approve() and then transfer(), your user can perform both in a single transaction.

For security reasons, there is a limit of 9 interactions per transaction intent.

curl

curl https://api.openfort.io/v1/transaction_intents \
  -H "Authorization: Bearer $YOUR_SECRET_KEY" \
  -d player="pla_...", \
  -d policy="pol_..." \
  -d chainId=80002 \
  -d optimistic=true \
  -d "interactions[0][contract]=con_..." \
  -d "interactions[0][functionName]=mint" \
  -d "interactions[0][functionArgs][0]=0x63B7...484f" \
  -d "interactions[1][contract]=con_..." \
  -d "interactions[1][functionName]=transfer" \
  -d "interactions[1][functionArgs][0]=0x32B7...213d"

2. Sign Transaction on Client

Use the nextAction returned by the backend to sign the transaction with the embedded wallet.

The transaction will be automatically signed and broadcasted by using the sendSignatureTransactionIntentRequest method.

const handleCollectButtonClick = async () => {
  const collectResponse = await fetch(`https://your-backend.com/api/mint`, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
    },
  });
  const collectResponseJSON = await collectResponse.json();
 
  if (collectResponseJSON.data?.nextAction) {
    // This example assumes you have already checked that Openfort 'embeddedState' is 
    // `ready` and the user is `authenticated`
    const response = await openfort.sendSignatureTransactionIntentRequest(
      collectResponseJSON.data.id,
      collectResponseJSON.data.nextAction.payload.userOperationHash
    );
    console.log("response", response);
  }
  console.log("success:", collectResponseJSON.data);
};