- Sui v0.9.0
Working title: syrup (to be changed)
NFT liquidity layer is a suite of modules which aim to bring NFT trading across marketplaces to a single point, thereby concentrating the liquidity into a common interface.
$ sui move build
Orderbook implementation where bids are fungible tokens and asks are NFTs. A bid is a request to buy one NFT from a specific collection. An ask is one NFT with a min price condition.
Ask is an object which is associated with a single NFT.
When Ask is created, we transfer the ownership of the NFT to this
new object. To be more precise, we transfer the safe::TransferCap.
One can:
- create a new orderbook between a given collection and a BID token (witness pattern protected)
- set publicly accessible actions to be witness protected
- open a new BID
- cancel an existing BID they own
- offer an NFT if a collection matches OB collection
- cancel an existing NFT offer
- instantly buy a specific NFT
The contract which creates the orderbook can restrict specific actions to be called only with a witness pattern and not via the entry point function. This means others can build contracts on top of the orderbook with their own custom logic based on their requirements or they can just use the entry point functions that cover other use cases.
If a method is protected, clients will need to call a standard endpoint in the witness-owning smart contract instead of the relevant endpoint in the orderbook. Another way to think about this from a marketplace or wallet POV: if I see that an action is protected, I can decide to either call the downstream implementation in the collection smart contract, or simply disable that specific action.
An example of this would be an NFT which has an expiry date like a name service which requires an additional check before an ask can be placed on the orderbook. Marketplaces can choose to support this additional logic or simply use the standard orderbook and enable bids but asks would be disabled until they decide to support the additional checks.
The setting is stored on the orderbook object:
struct WitnessProtectedActions has store {
buy_nft: bool,
cancel_ask: bool,
cancel_bid: bool,
create_ask: bool,
create_bid: bool,
}This means that the additional complexity is (i) opt-in by the collection and (ii) reserved only to the particular action which warrants that complexity.
To reiterate, a marketplace can list NFTs from collections that have all actions unprotected, ie. no special logic. Or they can just disable that particular action that is disabled in the UI.
Additionally, if we created a standard interface for custom implementations of the disabled actions, then the added opt-in complexity could be abstracted away from the clients by our SDK.
TBD: Can this be misused by removing the option to cancel an ask/bid?