CZ4153_DutchAuction: ChainBid

Blockchain Project to build a DutchAuction

PROJECT MEMBERS

• Sankar Samiksha
• Poon Yan Xin Melise

The project video submission of higher quality can be found below:

https://youtu.be/X0FkcZmnmsc

PROJECT REQUIREMENTS

Feature Requirement
Dutch Auction smart contracts should:

• Firstly, define and implement your new token using the ERC20 standard
• Implement Dutch auction logic in another contract(s)
• Only elapse for 20 minutes, either all tokens get sold out at clearing price no lower than the reserved price, or only part of total token supply get sold with the remaining tokens burned by the auction contract
• Be able to distribute the token minted to legitimate bidders at the end of the auction
• (bonus) add tests to demonstrate the auction contract is resistant to reentry attack.
• What is reentry attack,
• hands-on practice on reentry.

Tricky Points to Ponder

• How to enforce auction duration/countdown clock in blockchain?
• How to link/wrap your token contract with your auction contract?
• How to "burn" the unsold tokens?
• How to enforce successful bidder to pay Ether for the new token, (I.e., they can’t cancel the bid) and how to refund bids that are invalid?

CLONING THE REPOSITORY AND INSTALLING PACKAGES

git clone https://github.com/S-Samiksha/CZ4153_DutchAuction/tree/main
cd BackEnd_Contract
yarn
cd ..
cd Client
yarn

CONFIGURATIONS

CONSTRUCTOR

Parameters: _reservePrice: The minimum price of tokens
_startPrice : The starting price of a token

constructor(uint256 _reservePrice, uint256 _startPrice) {
        require(
            _reservePrice < _startPrice,
            "reserve price is higher than current price"
        );
        i_owner = msg.sender;
        reservePrice = _reservePrice;
        currentPrice = int256(_startPrice);
        startPrice = _startPrice;

        s_auctionState = AuctionState.CLOSING;
    }

Configuration File

1. Navigate to the helper-hardhat-config.js
2. Change the parameters according to the reserve price, start price you want

const INITIAL_SUPPLY_INT = 200;
const INITIAL_SUPPLY = (INITIAL_SUPPLY_INT * 10 ** 18).toString();
const RESERVE_PRICE = 10;
const START_PRICE = 50;
const INTERVAL = 30;
const CHANGEPERMIN = 15;

ADDING HARHDAT WALLETS TO METAMASK

Finding Private Keys of Hardhat Wallets

1. Run yarn hardhat node
2. Copy one of the private keys. The first account is the owner by default.

Add Account

1. Press the button + Add account or hardware wallet

Import Account

1. Press the Import account button

Paste Private Key

1. Paste the private key copied earlier
2. Click Import

Final State

DEPLOYING THE CONTRACT & FRONTEND

If you have BASH:

1. Open one terminal for backend

cd BackEnd_Contract
chmod +x run.sh
./run.sh

2. Open second terminal for front-end

cd Client 
yarn dev

If you do not have BASH:

1. Open the first terminal

cd BackEnd_Contract
yarn hardhat node

2. Open a second terminal

cd BackEnd_Contract
yarn hardhat run scripts/calculate.js --network localhost

3. Open a third terminal for front end

cd Client 
yarn dev

Finally

1. Open a browser withe the metamask that has the hardhat wallet accounts
2. Navigate to http://localhost:3000

To End On all running terminals, press ctr+c to end.

STARTING THE AUCTION

Parameters:
_totalAlgosAvailable: Total number of tokens to be mint for this round of auction
_changePerMin: rate of reduction of ETH cost per token. E.g. 10 wei/min means that the cost of one token will fall by 10 wei per min.

function startAuction(
        uint256 _totalAlgosAvailable,
        uint256 _changePerMin
    ) public onlyOwner AuctionClosed returns (address) {
        s_auctionState = AuctionState.OPEN;
        totalAlgosAvailable = _totalAlgosAvailable;
        changePerMin = _changePerMin;
        startTime = block.timestamp; //Start time of when the contract is deployed
        DAToken = new ERC20Token(totalAlgosAvailable, address(this));
        ERC20ContractAddress = address(DAToken);
        emit startAuctionEvent(
            startTime,
            ERC20ContractAddress,
            totalAlgosAvailable,
            changePerMin
        );
        return ERC20ContractAddress;
    }

Interacting with the Start Button in the UI

1. Add in the number of Algos/Tokens you want the auction to hold
2. Add in the rate of reduction you want

HARDHAT TEST SCRIPTS

To run the test scripts that is used to test the contract, run the following:

cd BackEnd_Contract
yarn hardhat test

RE ENTRANCY ATTACK

To see the re entrancy attack, run the following:

cd BackEnd_Vulnerable
yarn hardhat test

You will be able to see the following:

References:

https://github.com/lamtlo/Solidity-Dutch-Auction/blob/master/contracts/Auction.sol
https://www.algorand.foundation/algo-auction-overview
https://github.com/reddio-com/NFT-Marketplace
https://github.com/BlockchainCourseNTU/hello-dapp/tree/AY2023-AY2024