Uniswap V3 AlphaRouter Example

.env

WALLET_ADDRESS=
WALLET_SECRET=
INFURA_TEST_URL=

abi.json

[
  {
    "inputs": [],
    "stateMutability": "nonpayable",
    "type": "constructor"
  },
  {
    "anonymous": false,
    "inputs": [
      {
        "indexed": true,
        "internalType": "address",
        "name": "owner",
        "type": "address"
      },
      {
        "indexed": true,
        "internalType": "address",
        "name": "spender",
        "type": "address"
      },
      {
        "indexed": false,
        "internalType": "uint256",
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "Approval",
    "type": "event"
  },
  {
    "anonymous": false,
    "inputs": [
      {
        "indexed": true,
        "internalType": "address",
        "name": "from",
        "type": "address"
      },
      {
        "indexed": true,
        "internalType": "address",
        "name": "to",
        "type": "address"
      },
      {
        "indexed": false,
        "internalType": "uint256",
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "Transfer",
    "type": "event"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "owner",
        "type": "address"
      },
      {
        "internalType": "address",
        "name": "spender",
        "type": "address"
      }
    ],
    "name": "allowance",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "spender",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "amount",
        "type": "uint256"
      }
    ],
    "name": "approve",
    "outputs": [
      {
        "internalType": "bool",
        "name": "",
        "type": "bool"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "account",
        "type": "address"
      }
    ],
    "name": "balanceOf",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "decimals",
    "outputs": [
      {
        "internalType": "uint8",
        "name": "",
        "type": "uint8"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "spender",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "subtractedValue",
        "type": "uint256"
      }
    ],
    "name": "decreaseAllowance",
    "outputs": [
      {
        "internalType": "bool",
        "name": "",
        "type": "bool"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "spender",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "addedValue",
        "type": "uint256"
      }
    ],
    "name": "increaseAllowance",
    "outputs": [
      {
        "internalType": "bool",
        "name": "",
        "type": "bool"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "name",
    "outputs": [
      {
        "internalType": "string",
        "name": "",
        "type": "string"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "symbol",
    "outputs": [
      {
        "internalType": "string",
        "name": "",
        "type": "string"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "totalSupply",
    "outputs": [
      {
        "internalType": "uint256",
        "name": "",
        "type": "uint256"
      }
    ],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "to",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "amount",
        "type": "uint256"
      }
    ],
    "name": "transfer",
    "outputs": [
      {
        "internalType": "bool",
        "name": "",
        "type": "bool"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      {
        "internalType": "address",
        "name": "from",
        "type": "address"
      },
      {
        "internalType": "address",
        "name": "to",
        "type": "address"
      },
      {
        "internalType": "uint256",
        "name": "amount",
        "type": "uint256"
      }
    ],
    "name": "transferFrom",
    "outputs": [
      {
        "internalType": "bool",
        "name": "",
        "type": "bool"
      }
    ],
    "stateMutability": "nonpayable",
    "type": "function"
  }
]

package.json

{
  "name": "uniswap-alpha-router",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@uniswap/sdk": "^3.0.3",
    "@uniswap/sdk-core": "^3.0.1",
    "@uniswap/smart-order-router": "^2.5.30",
    "dotenv": "^16.0.1",
    "ethers": "^5.6.6",
    "jsbi": "^3.2.5"
  }
}

runAlphaRouter.js

const { AlphaRouter } = require('@uniswap/smart-order-router')
const { Token, CurrencyAmount, TradeType, Percent } = require('@uniswap/sdk-core')
const { ethers, BigNumber } = require('ethers')
const JSBI  = require('jsbi') // jsbi@3.2.5

const V3_SWAP_ROUTER_ADDRESS = '0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45'

require('dotenv').config()
const WALLET_ADDRESS = process.env.WALLET_ADDRESS
const WALLET_SECRET = process.env.WALLET_SECRET
const INFURA_TEST_URL = process.env.INFURA_TEST_URL

const web3Provider = new ethers.providers.JsonRpcProvider(INFURA_TEST_URL) // Ropsten

const chainId = 3
const router = new AlphaRouter({ chainId: chainId, provider: web3Provider})

const name0 = 'Wrapped Ether'
const symbol0 = 'WETH'
const decimals0 = 18
const address0 = '0xc778417e063141139fce010982780140aa0cd5ab'

const name1 = 'Uniswap Token'
const symbol1 = 'UNI'
const decimals1 = 18
const address1 = '0x1f9840a85d5af5bf1d1762f925bdaddc4201f984'

const WETH = new Token(chainId, address0, decimals0, symbol0, name0)
const UNI = new Token(chainId, address1, decimals1, symbol1, name1)

const wei = ethers.utils.parseUnits('0.01', 18)
const inputAmount = CurrencyAmount.fromRawAmount(WETH, JSBI.BigInt(wei))

async function main() {
  const route = await router.route(
    inputAmount,
    UNI,
    TradeType.EXACT_INPUT,
    {
      recipient: WALLET_ADDRESS,
      slippageTolerance: new Percent(25, 100),
      deadline: Math.floor(Date.now()/1000 + 1800)
    }
  )

  console.log(`Quote Exact In: ${route.quote.toFixed(10)}`)

  const transaction = {
    data: route.methodParameters.calldata,
    to: V3_SWAP_ROUTER_ADDRESS,
    value: BigNumber.from(route.methodParameters.value),
    from: WALLET_ADDRESS,
    gasPrice: BigNumber.from(route.gasPriceWei),
    gasLimit: ethers.utils.hexlify(1000000)
  }

  const wallet = new ethers.Wallet(WALLET_SECRET)
  const connectedWallet = wallet.connect(web3Provider)

  const approvalAmount = ethers.utils.parseUnits('1', 18).toString()
  const ERC20ABI = require('./abi.json')
  const contract0 = new ethers.Contract(address0, ERC20ABI, web3Provider)
  await contract0.connect(connectedWallet).approve(
    V3_SWAP_ROUTER_ADDRESS,
    approvalAmount
  )

  const tradeTransaction = await connectedWallet.sendTransaction(transaction)
}

main()

Hello Blockman, was trying to follow this tutorial that you made on youtube. I'm testing it on Sepolia Network, changed the addresses to match the ones in Sepolia. But I'm getting an error that the "execution reverted". Here's a transaction hash of one of the transaction:- 0x2efea2b5c729d85c757948c08ccc28205002b9bda4e196864f888bbb24aca263.

What could I be doing wrong?

Even with an exact mirror of the code, mirror of the dependencies and the whole project, the example simply does not work.

The libraries of uniswap and ethers changes constantly, so neither of the examples in the web works for a simple swap remotely via js, It's the curse of the js community.