How to estimate input amount for sushiswap?

Question

For estimation of input amount of tokens while calling quoteExactOutputSingle I use following for uni v2

const pair = await Fetcher.fetchPairData(tokenFrom, tokenTo, provider);

const route = new Route([pair], tokenFrom, tokenTo);
const amountOut = new TokenAmount(tokenTo, amountTo.toString());

const trade = Trade.exactOut(route, amountOut);

const amountIn = ethers.BigNumber.from(trade.inputAmount.raw.toString());

and for uni v3

const quoterContract = getUniswap3QuaterContract();
const amountIn = await quoterContract.callStatic.quoteExactOutputSingle(
    tokenFromAddress,
    tokenToAddress,
    fee,
    amountOut,
    0
);

Does anyone know how to estimate token amount in for sushiswap?

Answer 1

How to fetch amountOut and AmountIn from Sushiswap

Sushiswap V2Router02 address is: 0xd9e1cE17f2641f24aE83637ab66a2cca9C378B9F

Follow the next steps to interact with it.

1. Get the ABI from https://etherscan.io/address/0xd9e1cE17f2641f24aE83637ab66a2cca9C378B9F#code (at the button of the page)

2. Implement the code like this:

(Using EtherJS)

const USDC = { address: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48', decimal: 6 };
const WETH = { address: '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2', decimal: 18 }
const SushiSwapRouterABI = [.........]
var amount = 100

let quoterContractSushi = new ethers.Contract('0xd9e1cE17f2641f24aE83637ab66a2cca9C378B9F', SushiSwapRouterABI, signer)

// For Amount In
// As in ABI: getAmountsIn(uint256,address[])
let quoteIn = await quoterContractSushi.getAmountsIn(BigInt(amount * (10 ** USDC.decimal)), [USDC.address, WETH.address])

   console.log(quoteIn[0])

//For Amount Out
// As in ABI: getAmountsOut(uint256,address[])
let quoteOut = await quoterContractSushi.getAmountsOut(BigInt(amount * (10 ** USDC.decimal)), [USDC.address, WETH.address])

   console.log(quoteOut[1])

• Since it's a view-flagged function on the contract, "staticCall" is unnecessary.

Be aware of the fact that the return value In both methods must be a

amounts   uint256[]

Where the [0] is the amount In and the [1] is the amount Out

Good luck