CODEWITHSUNDEEP
ethereumsoliditysmartcontractsuniswap
kosccak93
kosccak93

Reputation: 11

Uniswap v3 custom ERC20 token swap

I am trying to implement a token swap of my custom ERC20 token via UniswapV3

I use Rinkeby Ethereum network.

I deployed the token under address: 0x4646CB39EA04d4763BED770F80F0e0dE8efcdF0f

I added the liquidity to Uniswap for this token and ETH.

Now, I try to execute swap in my contract, but it doesn't work. I get the error:

Gas estimation errored with the following message (see below). The transaction execution will likely fail. Do you want to force sending?
execution reverted

My Swap.sol contract takes an address of the token to swap with ETH as a constructor parameter. When I deploy it using DAI token address, the swap works just fine.

I assume this is a Uniswap liquidity related problem, but I added liquidity manually and I can swap my token inside their app.

Contract code:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.10;
pragma abicoder v2;

import "@uniswap/v3-periphery/contracts/libraries/TransferHelper.sol";
import "@uniswap/v3-periphery/contracts/interfaces/ISwapRouter.sol";
import "@uniswap/v3-periphery/contracts/interfaces/IQuoter.sol";


contract Swap {
    address private constant SWAP_ROUTER =
        0xE592427A0AEce92De3Edee1F18E0157C05861564;
    address private constant WETH = 0xc778417E063141139Fce010982780140Aa0cD5Ab;
    address public tokenAddress;

    address public immutable _owner;
    ISwapRouter public immutable swapRouter;

    constructor(address token) {
        _owner = msg.sender;
        swapRouter = ISwapRouter(SWAP_ROUTER);
        tokenAddress = token;
    }

    function swapExactInputSingle() external payable {
        require(msg.value > 0, "Must pass non 0 ETH amount");
        ISwapRouter.ExactInputSingleParams memory params = ISwapRouter
            .ExactInputSingleParams({
                tokenIn: WETH,
                tokenOut: tokenAddress,
                fee: 3000,
                recipient: msg.sender,
                deadline: block.timestamp,
                amountIn: msg.value,
                amountOutMinimum: 1,
                sqrtPriceLimitX96: 0
            });

        swapRouter.exactInputSingle{value: msg.value}(params);
    }

    receive() external payable {}
}

Upvotes: 1

Views: 1693

Answers (2)

way4way
way4way

Reputation: 21

I had the same issue with the swapExactInputMultihop function on uniswap. For each pools/paths you're going through, you need to make sure you've got the correct pool fee set.

You can checkout the swap fees on the uniswap website: V3-overview/fees

or on a video tutorial, going through the whole process: Blockchain With Wisdom on YouTube

Upvotes: 2

kosccak93
kosccak93

Reputation: 11

Managed to fix it.

I set the fee: 3000 in contract, but I created liquidity with 1% fee, so I had to change it to fee: 10000 according to docs: fee The fee tier of the pool, used to determine the correct pool contract in which to execute the swap

Upvotes: 0

Related Questions