run-arbitrage.js

require("dotenv").config()
const Web3 = require('web3');
const abis = require('./abis');
const { mainnet: addresses } = require('./addresses');

const web3 = new Web3(
  new Web3.providers.WebsocketProvider(process.env.INFURA_URL)
);

const quickswap = new web3.eth.Contract(
  abis.quickswap,
  addresses.quickswap.router
)

const sushi = new web3.eth.Contract(
  abis.quickswap,
  addresses.sushi.router
)

const AMOUNT_IN_WEI = web3.utils.toBN(web3.utils.toWei('1000'));

let badPairs = [];

const init = async () => {
  while (true) {
    for (var tokenAName in addresses.tokens) {
      for (var tokenBName in addresses.tokens) {
        if (tokenAName != tokenBName) {
          if (!badPairs.includes(tokenAName + ' ' + tokenBName)) {
            console.log('Pair: ' + tokenAName + ' ' + tokenBName);

            let tokenAAddress = addresses.tokens[tokenAName];
            let tokenBAddress = addresses.tokens[tokenBName];

            try {
              const amountsOut1 = await sushi.methods.getAmountsOut(AMOUNT_IN_WEI, [tokenAAddress, tokenBAddress]).call();
              const amountsOut2 = await quickswap.methods.getAmountsOut(amountsOut1[1], [tokenBAddress, tokenAAddress]).call();
              const amountsOut3 = await quickswap.methods.getAmountsOut(AMOUNT_IN_WEI, [tokenAAddress, tokenBAddress]).call();
              const amountsOut4 = await sushi.methods.getAmountsOut(amountsOut3[1], [tokenBAddress, tokenAAddress]).call();

              console.log(`Sushi -> quickswap. input / output: 
              ${web3.utils.fromWei(AMOUNT_IN_WEI.toString())} / 
              ${web3.utils.fromWei(amountsOut2[1].toString())}`);

              console.log(`quickswap -> Sushi. input / output: 
              ${web3.utils.fromWei(AMOUNT_IN_WEI.toString())} / 
              ${web3.utils.fromWei(amountsOut4[1].toString())}`);

              if (web3.utils.fromWei(amountsOut2[1].toString()) < 500) {
                badPairs.push(tokenAName + ' ' + tokenBName);
                console.log("bad pair");
              }
              if (web3.utils.fromWei(amountsOut4[1].toString()) < 500) {
                badPairs.push(tokenAName + ' ' + tokenBName);
                console.log("bad pair");
              }

              const resultFromQuickSwap = web3.utils.toBN(amountsOut2[1])
              const resultFromSushiSwap = web3.utils.toBN(amountsOut4[1])

              if (resultFromQuickSwap.gt(AMOUNT_IN_WEI)) {

                const profit = resultFromQuickSwap.sub(AMOUNT_IN_WEI);

                if (profit > 0) {
                  console.log('Arb opportunity found SushiSwap -> QuickSwap!');
                  console.log('Expected profit: ' + web3.utils.fromWei(profit).toString() + " " + tokenAName);
                }
              }

              if (resultFromSushiSwap.gt(AMOUNT_IN_WEI)) {

                const profit = resultFromSushiSwap.sub(AMOUNT_IN_WEI);

                if (profit > 0) {
                  console.log('Arb opportunity found QuickSwap -> SushiSwap!');
                  console.log('Expected profit: ' + web3.utils.fromWei(profit).toString() + " " + tokenAName);
                }
              }

            }
            catch (e) {
              badPairs.push(tokenAName + ' ' + tokenBName);
              console.log('some error');

            }
          }
        }
      }
    }
  }
}

init();