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MPC Wallets

expand.network supports the following MPC wallets:

DFNS
FORDEFI
FIREBLOCKS
CIRCLE

DFNS

Dfns is a cybersecurity company providing crypto wallet infrastructure. The company develops a wallet-as-a-service infrastructure in Web3. To use DFNS with expand.network SDK, follow these steps:-

Step 1: Installation

User needs to install the expand.network SDK using the following command:

npm i expand-network

Step 2: Wallet Initialisation

const { WalletDFNS , prepareTransaction } = require('expand-network');
async function initialiseDFNSWallet(){
    const options = {};
    options.privateKey = process.env.DFNS_PRIVATE_KEY;
    options.credId = process.env.DFNS_CRED_ID;
    options.xApiKey = process.env.X_API_KEY;
    options.appId = process.env.DFNS_APP_ID;
    options.authToken = process.env.DFNS_ACCESS_TOKEN;
    options.baseUrl = process.env.DFNS_API_URL;
    options.walletId = process.env.WALLET_ID;
    options.appOrigin = 'http://localhost:3000';
    const wallet  = await new WalletDFNS(options);
    return wallet;
}

const wallet = await initialiseDFNSWallet();    // Initialise the wallet client

Step 3: Prepare Transaction

// Preparing the approve transaction from expand.network
const prepareApproveTx = await prepareTransaction('https://api.expand.network/fungibletoken/approve', {       
        "from": "OWNER_WALLET_ADDRESS",
        "tokenAddress": "TOKEN_CONTRACT_ADDRESS",
        "to": "SPENDER_WALLET_ADDRESS",
        "amount": "100000",
        "gas": "25000",
        "xApiKey": "YOUR_API_KEY"     // Replace this with your API Key
    });
prepareApproveTx.chainId = '1';

Step 4: Sign Transaction

// Sign the transaction locally using sdk client
const approveSignedTx = await wallet.signTransaction(prepareApproveTx);         
approveSignedTx.chainId = '1';  // Replace with other chainId to toggle between chains

Step 5: Send Transaction

// Send the signed transaction
let txHash = await wallet.sendTransaction(approveSignedTx);         
console.log(`approve transaction: https://etherscan.io/tx/${txHash.TxHash}`);  // Confirmation

Sample code to perform a swap using DFNS:

const { WalletDFNS , prepareTransaction } = require('expand-network');
const dotenv = require('dotenv');
async function initialiseDFNSWallet(){
    const options = {};
    options.privateKey = process.env.DFNS_PRIVATE_KEY;
    options.credId = process.env.DFNS_CRED_ID;
    options.xApiKey = process.env.X_API_KEY;
    options.appId = process.env.DFNS_APP_ID;
    options.authToken = process.env.DFNS_ACCESS_TOKEN
    options.baseUrl = process.env.DFNS_API_URL;
    options.walletId = process.env.WALLET_ID;
    options.appOrigin = 'http://localhost:3000';
    const wallet  = await new WalletDFNS(options);
    return wallet;
}

async function main() {
    dotenv.config();            
    const wallet = await initialiseDFNSWallet();            // Initialise the wallet client
    const xApiKey = process.env.X_API_KEY;      
    const prepareApproveTx = await prepareTransaction('https://api.expand.network/fungibletoken/approve', {       // Prepare the approve transaction from expand.network
        "from": "OWNER_WALLET_ADDRESS",
        "tokenAddress": "TOKEN_CONTRACT_ADDRESS",
        "to": "SPENDER_WALLET_ADDRESS",
        "amount": "100000",
        "gas": "25000",
        "xApiKey": "YOUR_API_KEY"                     // Replace this with your API Key
    });
    prepareApproveTx.chainId = '1';          // Replace with other chainId to toggle between chains

    const approveSignedTx = await wallet.signTransaction(prepareApproveTx);             // Sign the transaction locally using sdk client

    approveSignedTx.chainId = '1';          // Replace with other chainId to toggle between chains
              

    let txHash = await wallet.sendTransaction(approveSignedTx);                 // Send the transaction
    console.log(`approve transaction: https://etherscan.io/tx/${txHash.TxHash}`);          // Confirmation
    
    const swapTransaction = await prepareTransaction('https://api.expand.network/dex/swap',{            // Simlarly build the swap Tx
            "dexId":"1000",  // Replace with other dexId to toggle between dexs
            "amountIn": "100000",
            "amountOutMin": "0",
            "path": ["TOKEN_ADDRESS_TO_SWAP_FROM","TOKEN_ADDRESS_TO_SWAP_TO"],
            "to": "RECEIVER_WALLET_ADDRESS",
            "deadline": "1965990894",
            "from": "SENDER_WALLET_ADDRESS",
            "gas": "173376",
            "xApiKey": "YOUR_API_KEY"               // Replace this with your API Key
    });
    console.log(swapTransaction);
    swapTransaction.chainId = '1';              // Replace with other chainId to toggle between chains

    const swapSignedTx = await wallet.signTransaction(swapTransaction);
    swapSignedTx.chainId = '1'                  // Replace with other chainId to toggle between chains

    const txHash1 = await wallet.sendTransaction(swapSignedTx);
    console.log(`swap transaction: https://etherscan.io/tx/${txHash1.TxHash}`);
}
main();

FORDEFI

Fordefi is an institutional MPC wallet and security platform built for decentralized finance (DeFi), offering MPC key management, self-serve DeFi policy controls, time-of-transaction smart contract insights, transaction simulation and risk alerts. To use FORDEFI with expand.network SDK, follow these steps:-

Step 1: Installation

User needs to install the expand.network SDK using the following command:

npm i expand-network

Step 2: Wallet Initialisation

const { WalletFordefi , prepareTransaction } = require('expand-network');
async function initialiseFordefiWallet(){
    const options = {
      accessToken: 'YOUR_ACCESS_TOKEN',  //Replace this with your bearer token
      xApiKey: 'YOUR_API_KEY',           //Replace this with your API key
      privateKeyFile: 'YOUR_PRIVATE_KEY', // Necessarily a .pem file
      vault_id: 'VAULT_ID'
    }
    const wallet  = new WalletFordefi(options);
    return wallet;
}

const wallet = await initialiseFordefiWallet();  //Initialise the wallet

Step 3: Prepare Transaction

// Preparing the approve transaction from expand.network
const preparedTx = await prepareTransaction("https://api.expand.network/fungibletoken/approve", {
        "from": "OWNER_WALLET_ADDRESS",
        "tokenAddress": "TOKEN_CONTRACT_ADDRESS",
        "to": "SPENDER_WALLET_ADDRESS",
        "amount": "100000",
        "gas": "25000",
         "chainId": "1",
        "xApiKey": "YOUR_API_KEY"     // Replace this with your API Key
    });
    preparedTx.chainId = '1';        // Replace with other chainId to toggle between chains

Step 4: Sign Transaction

// Sign the transaction locally using sdk client
const signedTx = await wallet.signTransaction(preparedTx);
console.log(signedTx);

Step 5: Send Transaction

// Send the signed transaction
const tx = await wallet.sendTransaction(signedTx);
console.log(tx);

Sample code to approve a fungible token using Fordefi:

const { WalletFordefi , prepareTransaction } = require('expand-network');
const xApiKey = 'YOUR_API_KEY';
const dotenv = require('dotenv');
async function initialiseFordefiWallet(){
    const options = {
      accessToken: 'YOUR_ACCESS_TOKEN',
      xApiKey:'YOUR_API_KEY',
      privateKeyFile: 'YOUR_PRIVATE_KEY_FILE',
      vault_id: 'VAULT_ID'
    }
    const wallet  = new WalletFordefi(options);
    return wallet;
}
async function main() {
    dotenv.config();
    const wallet = await initialiseFordefiWallet();
    const preparedTx = await prepareTransaction("https://api.expand.network/fungibletoken/approve", {
        "from": "OWNER_WALLET_ADDRESS",
        "tokenAddress":"TOKEN_CONTRACT_ADDRESS",
        "amount": "1000000000",
        "to": "SPENDER_WALLET_ADDRESS",
        "gas": "100000",
        "chainId": "1",
        "xApiKey": "YOUR_API_KEY"         
    });
    preparedTx.chainId = '1';
    const signedTx = await wallet.signTransaction(preparedTx);
    console.log(signedTx);
    const tx = await wallet.sendTransaction(signedTx);
    console.log(tx);
}
main();

FIREBLOCKS

The Fireblocks Network is a secure transfer network that allows you to instantly find, connect, and move digital assets across exchanges, fiat providers, liquidity partners, and counterparties.

To use FIREBLOCKS with expand.network SDK, follow these steps:-

Step 1: Installation

User needs to install the expand.network SDK using the following command:

npm i expand-network

Step 2: Wallet Initialisation

const {  WalletFireblocks, prepareTransaction } = require('expand-network');
const xApiKey = 'YOUR_API_KEY';                //Replace this with your API key
const dotenv = require('dotenv');
const fs = require('fs');
const path = require('path');
const apiSecret = fs.readFileSync(path.resolve("SECRET_KEY_FILE_PATH"), "utf8");
async function initialiseFireblocksWallet(){
    const options = {
      apiSecret: apiSecret,
      apiKey: "FIREBLOCKS_API_KEY",        //Replace this with your Fieblocks API key
    }
    const wallet  = new WalletFireblocks(options);
    return wallet;
}

const wallet = await initialiseFireblocksWallet();    //Initialise the wallet

Step 3: Prepare Transaction

// Preparing the approve transaction from expand.network
const preparedTx = await prepareTransaction("https://api.expand.network/fungibletoken/approve", {
        "from": "FIREBLOCKS_WALLET_ADDRESS",
        "tokenAddress":"0x6B175474E89094C44Da98b954EedeAC495271d0F",
        "amount": "10000",
        "to": "SPENDER_WALLET_ADDRESS",
        "gas": "100000",
        "chainId": "1",                    // Replace with other chainId to toggle between chains
        "xApiKey": "YOUR_API_KEY",        // Replace this with your API Key
    });

Step 4: Sign Transaction

// Sign the transaction locally using sdk client
const signedTx = await wallet.signTransaction(preparedTx);
console.log(signedTx);

Step 5: Send Transaction

// Send the signed transaction
const tx = await wallet.sendTransaction(signedTx);
console.log(tx);

Sample code to approve a fungible token using Fireblocks Wallet:

const {  WalletFireblocks, prepareTransaction } = require('expand-network');
const xApiKey = 'YOUR_API_KEY';
const dotenv = require('dotenv');
const fs = require('fs');
const path = require('path');
const apiSecret = fs.readFileSync(path.resolve("SECRET_KEY_FILE_PATH"), "utf8");
async function initialiseFireblocksWallet(){
    const options = {
      apiSecret: apiSecret,
      apiKey: "FIREBLOCKS_API_KEY",        
    }
    const wallet  = new WalletFireblocks(options);
    return wallet;
}
async function main() {
    dotenv.config();
    const wallet = await initialiseFireblocksWallet();
    const preparedTx = await prepareTransaction("https://api.expand.network/fungibletoken/approve", {
        "from": "FIREBLOCKS_WALLET_ADDRESS",
        "tokenAddress":"TOKEN_CONTRACT_ADDRESS",
        "amount": "10000",
        "to": "SPENDER_WALLET_ADDRESS",
        "gas": "100000",
        "chainId": "1",
        "xApiKey": "YOUR_API_KEY",
    });
    const signedTx = await wallet.signTransaction(preparedTx);
    console.log(signedTx);
    const tx = await wallet.sendTransaction(signedTx);
    console.log(tx);
}
main();

CIRCLE

Circle Programmable Wallets is a Wallet as a Service that simplifies creating and managing secure web3 wallets and their private keys. They extend wallet functionality with approachable user flows, provide optionality for developer and user infrastructure solutions, and enable seamless smart contract integration. To use CIRCLE with expand.network SDK, follow these steps:-

Step 1: Installation

User needs to install the expand.network SDK using the following command:

npm i expand-network

Step 2: Wallet Initialisation

async function initcircleWallet(options){
    const userToken = await WalletCircle.getUserToken(options);
    options.userToken = userToken.userToken;
    options.encryptionKey = userToken.encryptionKey;
    const wallet = new WalletCircle(options);
    return wallet;
}

Step 3: Prepare Transaction

// Preparing the approve transaction from expand.network
const prepareApproveTx = await prepareTransaction('https://api.expand.network/fungibletoken/approve', {
        "from": "SENDER_ADDRESS",
        "tokenAddress": "0xdc31Ee1784292379Fbb2964b3B9C4124D8F89C60",
        "to": "RECEIVER_ADDRESS",
        "amount": "10000",
        "gas": "25000",
        "xApiKey": 'YOUR_API_KEY'        //Replace with your API key
    });

Step 4: Sign Transaction

// Sign the transaction locally using sdk client
const signedTx = await wallet.signTransaction(prepareApproveTx);
console.log("signedTx: " ,signedTx);

Step 5: Send Transaction

// Send the signed transaction
const tx = await wallet.sendTransaction(signedTx);
console.log("sent tx: ", tx);

Sample code to approve a fungible token using Circle:

const { WalletCircle, prepareTransaction } = require('expand-network');
async function initcircleWallet(options){
    const userToken = await WalletCircle.getUserToken(options);
    options.userToken = userToken.userToken;
    options.encryptionKey = userToken.encryptionKey;
    const wallet = new WalletCircle(options);
    return wallet;
}
async function main(){
    const wallet = await initcircleWallet({
        appId: "CIRCLE_APP_ID",
        apiKey: 'CIRCLE_API_KEY',
        userId: 'CIRCLE_USER_ID',
        walletId: 'CIRCLE_WALLET_ID',
        encryptionKey: 'CIRCLE_ENCRYPTION_KEY'
    });
    const prepareApproveTx = await prepareTransaction('https://api.expand.network/fungibletoken/approve', {
        "from": "SENDER_ADDRESS",
        "tokenAddress": "0xdc31Ee1784292379Fbb2964b3B9C4124D8F89C60",
        "to": "RECEIVER_ADDRESS",
        "amount": "10000",
        "gas": "25000",
        "xApiKey": 'YOUR_API_KEY'
    });
    const signedTx = await wallet.signTransaction(prepareApproveTx);
    console.log("signedTx: " ,signedTx);
    const tx = await wallet.sendTransaction(signedTx);
    console.log("sent tx: ", tx);
}
main();

FIREBLOCKS

The Fireblocks Network is a secure transfer network that allows you to instantly find, connect, and move digital assets across exchanges, fiat providers, liquidity partners, and counterparties.

To use FIREBLOCKS with expand.network SDK, follow these steps:-

Step 1: Installation

User needs to install the expand.network SDK using the following command:

npm i expand-network

Step 2: Wallet Initialisation

const {  WalletFireblocks, prepareTransaction } = require('expand-network');
const xApiKey = 'YOUR_API_KEY';                //Replace this with your API key
const dotenv = require('dotenv');
const fs = require('fs');
const path = require('path');
const apiSecret = fs.readFileSync(path.resolve("SECRET_KEY_FILE_PATH"), "utf8");
async function initialiseFireblocksWallet(){
    const options = {
      apiSecret: apiSecret,
      apiKey: "FIREBLOCKS_API_KEY",        //Replace this with your Fieblocks API key
    }
    const wallet  = new WalletFireblocks(options);
    return wallet;
}

const wallet = await initialiseFireblocksWallet();    //Initialise the wallet

Step 3: Prepare Transaction

// Preparing the approve transaction from expand.network
const preparedTx = await prepareTransaction("https://api.expand.network/fungibletoken/approve", {
        "from": "FIREBLOCKS_WALLET_ADDRESS",
        "tokenAddress":"0x6B175474E89094C44Da98b954EedeAC495271d0F",
        "amount": "10000",
        "to": "SPENDER_WALLET_ADDRESS",
        "gas": "100000",
        "chainId": "1",                    // Replace with other chainId to toggle between chains
        "xApiKey": "YOUR_API_KEY",        // Replace this with your API Key
    });

Step 4: Sign Transaction

// Sign the transaction locally using sdk client
const signedTx = await wallet.signTransaction(preparedTx);
console.log(signedTx);

Step 5: Send Transaction

// Send the signed transaction
const tx = await wallet.sendTransaction(signedTx);
console.log(tx);

Sample code to approve a fungible token using Fireblocks Wallet:

const {  WalletFireblocks, prepareTransaction } = require('expand-network');
const xApiKey = 'YOUR_API_KEY';
const dotenv = require('dotenv');
const fs = require('fs');
const path = require('path');
const apiSecret = fs.readFileSync(path.resolve("SECRET_KEY_FILE_PATH"), "utf8");
async function initialiseFireblocksWallet(){
    const options = {
      apiSecret: apiSecret,
      apiKey: "FIREBLOCKS_API_KEY",        
    }
    const wallet  = new WalletFireblocks(options);
    return wallet;
}
async function main() {
    dotenv.config();
    const wallet = await initialiseFireblocksWallet();
    const preparedTx = await prepareTransaction("https://api.expand.network/fungibletoken/approve", {
        "from": "FIREBLOCKS_WALLET_ADDRESS",
        "tokenAddress":"TOKEN_CONTRACT_ADDRESS",
        "amount": "10000",
        "to": "SPENDER_WALLET_ADDRESS",
        "gas": "100000",
        "chainId": "1",
        "xApiKey": "YOUR_API_KEY",
    });
    const signedTx = await wallet.signTransaction(preparedTx);
    console.log(signedTx);
    const tx = await wallet.sendTransaction(signedTx);
    console.log(tx);
}
main();

DFNS

Step 1: Installation

User needs to install the expand.network SDK using the following command:

npm i expand-network

Step 2: Wallet Initialisation

const { WalletDFNS , prepareTransaction } = require('expand-network');
async function initialiseDFNSWallet(){
    const options = {};
    options.privateKey = process.env.DFNS_PRIVATE_KEY;
    options.credId = process.env.DFNS_CRED_ID;
    options.xApiKey = process.env.X_API_KEY;
    options.appId = process.env.DFNS_APP_ID;
    options.authToken = process.env.DFNS_ACCESS_TOKEN;
    options.baseUrl = process.env.DFNS_API_URL;
    options.walletId = process.env.WALLET_ID;
    options.appOrigin = 'http://localhost:3000';
    const wallet  = await new WalletDFNS(options);
    return wallet;
}

const wallet = await initialiseDFNSWallet();    // Initialise the wallet client

Step 3: Prepare Transaction

// Preparing the approve transaction from expand.network
const prepareApproveTx = await prepareTransaction('https://api.expand.network/fungibletoken/approve', {       
        "from": "OWNER_WALLET_ADDRESS",
        "tokenAddress": "TOKEN_CONTRACT_ADDRESS",
        "to": "SPENDER_WALLET_ADDRESS",
        "amount": "100000",
        "gas": "25000",
        "xApiKey": "YOUR_API_KEY"     // Replace this with your API Key
    });
prepareApproveTx.chainId = '1';

Step 4: Sign Transaction

// Sign the transaction locally using sdk client
const approveSignedTx = await wallet.signTransaction(prepareApproveTx);         
approveSignedTx.chainId = '1';  // Replace with other chainId to toggle between chains

Step 5: Send Transaction

// Send the signed transaction
let txHash = await wallet.sendTransaction(approveSignedTx);         
console.log(`approve transaction: https://etherscan.io/tx/${txHash.TxHash}`);  // Confirmation

Sample code to perform a swap using DFNS:

const { WalletDFNS , prepareTransaction } = require('expand-network');
const dotenv = require('dotenv');
async function initialiseDFNSWallet(){
    const options = {};
    options.privateKey = process.env.DFNS_PRIVATE_KEY;
    options.credId = process.env.DFNS_CRED_ID;
    options.xApiKey = process.env.X_API_KEY;
    options.appId = process.env.DFNS_APP_ID;
    options.authToken = process.env.DFNS_ACCESS_TOKEN
    options.baseUrl = process.env.DFNS_API_URL;
    options.walletId = process.env.WALLET_ID;
    options.appOrigin = 'http://localhost:3000';
    const wallet  = await new WalletDFNS(options);
    return wallet;
}

async function main() {
    dotenv.config();            
    const wallet = await initialiseDFNSWallet();            // Initialise the wallet client
    const xApiKey = process.env.X_API_KEY;      
    const prepareApproveTx = await prepareTransaction('https://api.expand.network/fungibletoken/approve', {       // Prepare the approve transaction from expand.network
        "from": "OWNER_WALLET_ADDRESS",
        "tokenAddress": "TOKEN_CONTRACT_ADDRESS",
        "to": "SPENDER_WALLET_ADDRESS",
        "amount": "100000",
        "gas": "25000",
        "xApiKey": "YOUR_API_KEY"                     // Replace this with your API Key
    });
    prepareApproveTx.chainId = '1';          // Replace with other chainId to toggle between chains

    const approveSignedTx = await wallet.signTransaction(prepareApproveTx);             // Sign the transaction locally using sdk client

    approveSignedTx.chainId = '1';          // Replace with other chainId to toggle between chains
              

    let txHash = await wallet.sendTransaction(approveSignedTx);                 // Send the transaction
    console.log(`approve transaction: https://etherscan.io/tx/${txHash.TxHash}`);          // Confirmation
    
    const swapTransaction = await prepareTransaction('https://api.expand.network/dex/swap',{            // Simlarly build the swap Tx
            "dexId":"1000",  // Replace with other dexId to toggle between dexs
            "amountIn": "100000",
            "amountOutMin": "0",
            "path": ["TOKEN_ADDRESS_TO_SWAP_FROM","TOKEN_ADDRESS_TO_SWAP_TO"],
            "to": "RECEIVER_WALLET_ADDRESS",
            "deadline": "1965990894",
            "from": "SENDER_WALLET_ADDRESS",
            "gas": "173376",
            "xApiKey": "YOUR_API_KEY"               // Replace this with your API Key
    });
    console.log(swapTransaction);
    swapTransaction.chainId = '1';              // Replace with other chainId to toggle between chains

    const swapSignedTx = await wallet.signTransaction(swapTransaction);
    swapSignedTx.chainId = '1'                  // Replace with other chainId to toggle between chains

    const txHash1 = await wallet.sendTransaction(swapSignedTx);
    console.log(`swap transaction: https://etherscan.io/tx/${txHash1.TxHash}`);
}
main();

FORDEFI

Step 1: Installation

User needs to install the expand.network SDK using the following command:

npm i expand-network

Step 2: Wallet Initialisation

const { WalletFordefi , prepareTransaction } = require('expand-network');
async function initialiseFordefiWallet(){
    const options = {
      accessToken: 'YOUR_ACCESS_TOKEN',  //Replace this with your bearer token
      xApiKey: 'YOUR_API_KEY',           //Replace this with your API key
      privateKeyFile: 'YOUR_PRIVATE_KEY', // Necessarily a .pem file
      vault_id: 'VAULT_ID'
    }
    const wallet  = new WalletFordefi(options);
    return wallet;
}

const wallet = await initialiseFordefiWallet();  //Initialise the wallet

Step 3: Prepare Transaction

// Preparing the approve transaction from expand.network
const preparedTx = await prepareTransaction("https://api.expand.network/fungibletoken/approve", {
        "from": "OWNER_WALLET_ADDRESS",
        "tokenAddress": "TOKEN_CONTRACT_ADDRESS",
        "to": "SPENDER_WALLET_ADDRESS",
        "amount": "100000",
        "gas": "25000",
         "chainId": "1",
        "xApiKey": "YOUR_API_KEY"     // Replace this with your API Key
    });
    preparedTx.chainId = '1';        // Replace with other chainId to toggle between chains

Step 4: Sign Transaction

// Sign the transaction locally using sdk client
const signedTx = await wallet.signTransaction(preparedTx);
console.log(signedTx);

Step 5: Send Transaction

// Send the signed transaction
const tx = await wallet.sendTransaction(signedTx);
console.log(tx);

Sample code to approve a fungible token using Fordefi:

const { WalletFordefi , prepareTransaction } = require('expand-network');
const xApiKey = 'YOUR_API_KEY';
const dotenv = require('dotenv');
async function initialiseFordefiWallet(){
    const options = {
      accessToken: 'YOUR_ACCESS_TOKEN',
      xApiKey:'YOUR_API_KEY',
      privateKeyFile: 'YOUR_PRIVATE_KEY_FILE',
      vault_id: 'VAULT_ID'
    }
    const wallet  = new WalletFordefi(options);
    return wallet;
}
async function main() {
    dotenv.config();
    const wallet = await initialiseFordefiWallet();
    const preparedTx = await prepareTransaction("https://api.expand.network/fungibletoken/approve", {
        "from": "OWNER_WALLET_ADDRESS",
        "tokenAddress":"TOKEN_CONTRACT_ADDRESS",
        "amount": "1000000000",
        "to": "SPENDER_WALLET_ADDRESS",
        "gas": "100000",
        "chainId": "1",
        "xApiKey": "YOUR_API_KEY"         
    });
    preparedTx.chainId = '1';
    const signedTx = await wallet.signTransaction(preparedTx);
    console.log(signedTx);
    const tx = await wallet.sendTransaction(signedTx);
    console.log(tx);
}
main();

CIRCLE

Step 1: Installation

User needs to install the expand.network SDK using the following command:

npm i expand-network

Step 2: Wallet Initialisation

async function initcircleWallet(options){
    const userToken = await WalletCircle.getUserToken(options);
    options.userToken = userToken.userToken;
    options.encryptionKey = userToken.encryptionKey;
    const wallet = new WalletCircle(options);
    return wallet;
}

Step 3: Prepare Transaction

// Preparing the approve transaction from expand.network
const prepareApproveTx = await prepareTransaction('https://api.expand.network/fungibletoken/approve', {
        "from": "SENDER_ADDRESS",
        "tokenAddress": "0xdc31Ee1784292379Fbb2964b3B9C4124D8F89C60",
        "to": "RECEIVER_ADDRESS",
        "amount": "10000",
        "gas": "25000",
        "xApiKey": 'YOUR_API_KEY'        //Replace with your API key
    });

Step 4: Sign Transaction

// Sign the transaction locally using sdk client
const signedTx = await wallet.signTransaction(prepareApproveTx);
console.log("signedTx: " ,signedTx);

Step 5: Send Transaction

// Send the signed transaction
const tx = await wallet.sendTransaction(signedTx);
console.log("sent tx: ", tx);

Sample code to approve a fungible token using Circle:

const { WalletCircle, prepareTransaction } = require('expand-network');
async function initcircleWallet(options){
    const userToken = await WalletCircle.getUserToken(options);
    options.userToken = userToken.userToken;
    options.encryptionKey = userToken.encryptionKey;
    const wallet = new WalletCircle(options);
    return wallet;
}
async function main(){
    const wallet = await initcircleWallet({
        appId: "CIRCLE_APP_ID",
        apiKey: 'CIRCLE_API_KEY',
        userId: 'CIRCLE_USER_ID',
        walletId: 'CIRCLE_WALLET_ID',
        encryptionKey: 'CIRCLE_ENCRYPTION_KEY'
    });
    const prepareApproveTx = await prepareTransaction('https://api.expand.network/fungibletoken/approve', {
        "from": "SENDER_ADDRESS",
        "tokenAddress": "0xdc31Ee1784292379Fbb2964b3B9C4124D8F89C60",
        "to": "RECEIVER_ADDRESS",
        "amount": "10000",
        "gas": "25000",
        "xApiKey": 'YOUR_API_KEY'
    });
    const signedTx = await wallet.signTransaction(prepareApproveTx);
    console.log("signedTx: " ,signedTx);
    const tx = await wallet.sendTransaction(signedTx);
    console.log("sent tx: ", tx);
}
main();