End-to-end Code Snippet
Here is how the entire script will look plugged together:
import { ethers, Contract } from 'ethers'
import axios from "axios"
const PATH_FINDER_API_URL = "https://api.pathfinder.routerprotocol.com/api"
const STATS_API_URL = "https://api.stats.routerprotocol.com/api"
const chainMapping = {
"137": {
"chain": "Polygon",
"rpc": "https://polygon-rpc.com",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0xfEd3c880FF02B195abee916328c5a3953976befD",
"NATIVE": {
"address": "0x0000000000000000000000000000000000001010",
"wrapped_address": "0x4c28f48448720e9000907BC2611F73022fdcE1fA"
}
},
"1": {
"chain": "Ethereum",
"rpc": "https://speedy-nodes-nyc.moralis.io/36a3a9840a5f2cc2ea2bbb42/eth/mainnet",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0x5e9A385a15cDE1b149Cb215d9cF3151096A37D67",
"NATIVE": {
"address": "0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE",
"wrapped_address": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2"
}
},
"250": {
"chain": "Fantom",
"rpc": "https://rpc.ftm.tools/",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0x621F0549102262148f6a7D289D8330adf7CbC09F",
"NATIVE": {
"address": "0x0100000000000000000000000000000000000001",
"wrapped_address": "0x21be370D5312f44cB42ce377BC9b8a0cEF1A4C83"
}
},
"42161": {
"chain": "Arbitrum",
"rpc": "https://arb1.arbitrum.io/rpc",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0x88b1E0ecaC05b876560eF072d51692F53932b16f",
"NATIVE": {
"address": "0x0000000000000000000000000000000000001010",
"wrapped_address": "0x82aF49447D8a07e3bd95BD0d56f35241523fBab1"
}
},
"56": {
"chain": "BSC",
"rpc": "https://bsc-dataseed.binance.org/",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0x45d880647Ec9BEF6Bff58ee6bB985C67d7234b0C",
"NATIVE": {
"address": "0x0100000000000000000000000000000000000001",
"wrapped_address": "0xbb4CdB9CBd36B01bD1cBaEBF2De08d9173bc095c"
}
},
"43114": {
"chain": "Avalanche",
"rpc": "https://api.avax.network/ext/bc/C/rpc",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0x5febcA23e97c8ead354318e5A3Ed34ec3704459a",
"NATIVE": {
"address": "0x0100000000000000000000000000000000000001",
"wrapped_address": "0xB31f66AA3C1e785363F0875A1B74E27b85FD66c7"
}
},
"10": {
"chain": "Optimism",
"rpc": "https://mainnet.optimism.io",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0x88b1E0ecaC05b876560eF072d51692F53932b16f",
"NATIVE": {
"address": "0x0000000000000000000000000000000000001010",
"wrapped_address": "0x4200000000000000000000000000000000000006"
}
},
"25": {
"chain": "Cronos",
"rpc": "https://evm.cronos.org",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0xf44Ff799eA2bBFeC96f9A50498209AAc3C2b3b8b",
"NATIVE": {
"address": "0x0000000000000000000000000000000000000001",
"wrapped_address": "0x5C7F8A570d578ED84E63fdFA7b1eE72dEae1AE23"
}
},
"1666600000": {
"chain": "Harmony",
"rpc": "https://api.harmony.one",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0x8413041a7702603d9d991F2C4ADd29e4e8A241F8",
"NATIVE": {
"address": "0x0000000000000000000000000000000000001010",
"wrapped_address": "0xcF664087a5bB0237a0BAd6742852ec6c8d69A27a"
}
},
"1313161554": {
"chain": "Aurora",
"rpc": "https://mainnet.aurora.dev",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0x13538f1450Ca2E1882Df650F87Eb996fF4Ffec34",
"NATIVE": {
"address": "0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE",
"wrapped_address": "0xC9BdeEd33CD01541e1eeD10f90519d2C06Fe3feB"
}
},
"2222": {
"chain": "Kava",
"rpc": "https://evm.kava.io",
"reserveHandler_address": "0x6e14f48576265272B6CAA3A7cC500a26050Be64E",
"oneSplit_address": "0xB065a867a1baa919F0A9a3F5C1543D19768CeFBD",
"NATIVE": {
"address": "0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE",
"wrapped_address": "0xc86c7C0eFbd6A49B35E8714C5f59D99De09A225b"
}
}
}
// ERC20 Contract ABI for "Approve" and "Allowance" functions
const erc20_abi = [
{
"name": "approve",
"inputs": [
{
"internalType": "address",
"name": "spender",
"type": "address"
},
{
"internalType": "uint256",
"name": "amount",
"type": "uint256"
}
],
"outputs": [
{
"internalType": "bool",
"name": "",
"type": "bool"
}
],
"stateMutability": "nonpayable",
"type": "function"
},
{
"name": "allowance",
"inputs": [
{
"internalType": "address",
"name": "owner",
"type": "address"
},
{
"internalType": "address",
"name": "spender",
"type": "address"
}
],
"outputs": [
{
"internalType": "uint256",
"name": "",
"type": "uint256"
}
],
"stateMutability": "view",
"type": "function"
}
];
// calling the pathfinder api using axios
const fetchPathfinderData = async (params) => {
const endpoint = "quote"
const pathUrl = `${PATH_FINDER_API_URL}/${endpoint}`
console.log(pathUrl)
try {
const res = await axios.get(pathUrl, { params })
return res.data
} catch (e) {
console.error(`Fetching data from pathfinder: ${e}`)
}
}
// calling the status api using axios
const fetchStatus = async (params) => {
const endpoint = "status"
const pathUrl = `${STATS_API_URL}/${endpoint}`
console.log(pathUrl)
try {
const res = await axios.get(pathUrl, { params })
return res.data
} catch (e) {
console.error(`Fetching data from API: ${e}`)
}
}
// Fetch the current allowance and update if needed
const checkAndSetAllowance = async (wallet, tokenAddress, approvalAddress, amount) => {
console.log('Approving token:', tokenAddress)
// Transactions with the native token don't need approval
if (tokenAddress === ethers.constants.AddressZero) {
return
}
const erc20 = new Contract(tokenAddress, erc20_abi, wallet);
const allowance = await erc20.allowance(await wallet.getAddress(), approvalAddress);
if (allowance.lt(amount)) {
const approveTx = await erc20.approve(approvalAddress, amount, { gasPrice: await wallet.provider.getGasPrice() });
try {
await approveTx.wait();
console.log(`Approval transaction mined succesfully: ${approveTx.hash}`)
}
catch (error) {
console.log(`Approval transaction failed with error: ${error}`)
}
}
}
const main = async () => {
const args = {
'fromTokenAddress': '0x0100000000000000000000000000000000000001', // FTM on Fantom
'toTokenAddress': '0x0000000000000000000000000000000000001010', // MATIC on Polygon
'amount': '1000000000000000000', // 1 FTM
'fromTokenChainId': 250, // Fantom
'toTokenChainId': 137, // Polygon
'userAddress': 'YOUR_ADDRESS',
'feeTokenAddress': '0x11BbF12363dC8375b78D2719395d505f52a02F68', // ROUTE on Fantom
'slippageTolerance': 2,
'widgetId': 24, // get your unique wdiget id by contacting us on Telegram
}
const pathfinder_response = await fetchPathfinderData(args)
// setting up wallet
let chainId = args.fromTokenChainId
const provider = new ethers.providers.JsonRpcProvider(chainMapping[chainId].rpc, chainId);
const wallet = new ethers.Wallet("YOUR_PRIVATE_KEY", provider)
console.log("Wallet setup successfully")
await checkAndSetAllowance(
wallet,
args.fromTokenAddress === chainMapping[chainId].NATIVE.address ? chainMapping[chainId].NATIVE.wrapped_address : args.fromTokenAddress, // fromTokenAddress
args.fromTokenChainId === args.toTokenChainId ? chainMapping[chainId].oneSplit_address : chainMapping[chainId].reserveHandler_address, // Router's OneSplit Address for same-chain transactions and Router's Reserve Token Handler for cross-chain transactions
ethers.constants.MaxUint256 // amount to approve
)
// if the fee token is not the same as the source token or if it is not a same-chain swap, giving approval for the fee token as well
if (args.feeTokenAddress.toUpperCase() !== args.fromTokenAddress.toUpperCase() && args.fromTokenChainId !== args.toTokenChainId) {
await checkAndSetAllowance(
wallet,
args.feeTokenAddress === chainMapping[chainId].NATIVE.address ? chainMapping[chainId].NATIVE.wrapped_address : args.feeTokenAddress, // feeTokenAddress
chainMapping[chainId].reserveHandler_address, // Router's Reserve Token Handler
ethers.constants.MaxUint256 // amount to approve
)
}
// setting the gas price and limit
if(!pathfinder_response.txn.execution.gasPrice){
pathfinder_response.txn.execution.gasPrice = await wallet.provider.getGasPrice()
}
if(pathfinder_response.txn.execution.value){
pathfinder_response.txn.execution.value = ethers.utils.hexlify(ethers.BigNumber.from(pathfinder_response.txn.execution.value))
}
if(!pathfinder_response.txn.execution.gasLimit){
pathfinder_response.txn.execution.gasLimit = ethers.utils.hexlify(ethers.BigNumber.from(1000000))
}
// sending the transaction using the data given by the pathfinder
const tx = await wallet.sendTransaction(pathfinder_response.txn.execution)
try {
await tx.wait();
console.log(`Deposit transaction mined successfully on the source chain: ${tx.hash}`)
}
catch (error) {
console.log(`Deposit transaction failed on the source chain with error: ${error}`)
return
}
let params = {
txHash: tx.hash,
networkId: args.fromTokenChainId // args were defined in step 1 to fetch data from the pathfinder
}
setTimeout(async function() {
let status = await fetchStatus(params)
console.log(status)
if (status.tx_status_code === 1) {
console.log("Transaction completed")
// handle the case where the transaction is complete
}
else if (status.tx_status_code === 0) {
console.log("Transaction still pending")
// handle the case where the transaction is still pending
}
}, 180000); // waiting for sometime before fetching the status of the transaction because it may take some time for the transaction to get indexed
}
main()
Even though the private key has been hardcoded in this example - to use this code for a UI, define the provider and signer using the following code snippet:
const provider = new ethers.providers.Web3Provider(window.ethereum);
await provider.send('eth_requestAccounts', []) // connects MetaMask
const signer = provider.getSigner()
Last modified 8mo ago