This is an automated auction system created for an unreleased NFT project. Users would be able to visit a front-end where they could compose their own artworks and then place a bid to mint it. The highest bid within a given auction period (default 24 hours) could then be minted as an NFT. All other bids remain in the queue for the next auction. These periodic auctions continue until the max number of mints allocated has been reached. See below for additional details on each contract.
Contains logic for periodic auctions. This is the main contract that the front-end will interact with to allow users to create, update, and cancel bids. This contract also defines the default auction period (24 hours) and the maximum number of NFTs that can be minted.
Includes mint function that can be called at the end of each auction period to mint an NFT from the highest bid. This function is permissionless so it could be called by bidders themselves, but the greater Abstract Browsing project automates this to provide a more fluid bidding & minting cycle. Will revert if the provided input parameters do not identify a valid bid or if the auction is still in progress.
The _factory state variable should be set to the address of the ERC721 contract that NFTs should be minted from. The provided ERC721 contract should also implement access controls that grant minting rights to PeriodicMinter
This contract contains implementation details for how bids and the collection of bids within the auction system are represented. The collection of bids is represented as a linked-list of Bid structs stored in a the Bids mapping indexed by BidId.
The BidId is computed by taking the keccak256 hash of the account that created the bid (bidder), the url (url) of the website that the abstracted artwork was sourced from, and the desired token URI (tokenUri) which points to the rendered image, i.e. keccak256(abi.encodePacked(bidder, url, tokenUri )).
Contains logic responsible for verifying that incoming bids can be trusted as originating from our back-end.
Each bid includes a token URI that points to the NFT metadata to be used in the case that the bid wins the auction and is minted. The image property in this metadata points to an image that is rendered on our back-end and persisted to IPFS. To prevent URIs pointing to arbitrary metadata from being accepted when a new bid is made, we need to verify that the metadata (and the included image) were generated on our back-end.
To accomplish this, bids are packaged up and cryptographically signed using EIP712 on our back-end using a trusted private-key.