NFT Auction Smart Contract

A decentralized NFT auction platform built on Ethereum that allows users to create auctions for their NFTs and accept bids from other users.

Features

• NFT owners can create auctions with custom reserve prices and durations
• Bidders can place bids on active auctions
• Automatic refund of outbid amounts
• Sellers can end auctions early if reserve price is met
• Built-in security with reentrancy protection
• Fully tested with Foundry

Contract Details

The main contract AuctionContract.sol implements the following key functionality:

• depositNft(): Create a new auction by depositing an NFT
• bid(): Place a bid on an active auction
• finishAuction(): Complete an auction after time expires
• sellerEndAuction(): Allow seller to end auction early if reserve met
• withdraw(): Withdraw refunded bid amounts
• getActiveAuctions(): View all currently active auctions

Technical Specifications

• Solidity version: 0.8.20
• Built with OpenZeppelin contracts
• Implements ERC721 receiver interface
• Uses ReentrancyGuard for security
• Comprehensive test suite in Foundry

Security Features

• Reentrancy protection on critical functions
• Checks-Effects-Interactions pattern
• Access control via Ownable
• Minimum auction duration enforcement
• Safe transfer handling

Testing

The contract includes extensive tests covering:

• NFT deposits
• Bidding functionality
• Auction completion
• Withdrawal mechanics
• Edge cases and security scenarios

Run tests with: forge test