Cardano Projected NFT

Different blockchains may have different block times & finality, so trying to guarantee the state of blockchain A from blockchain B often requires timelock systems like projected data.

This primitive implements the Projected NFT system and, given Cardano NFTs are treated the same as any other asset in a UTXO, is seamlessly extended to be a general projected asset system (it is not limited to NFTs).

If your use-case does not require a guarantee the data is up-to-date to the second, consider using the delayed state primitive instead.

Projected NFT

Example

extensions:
  - name: "projected-nft"
    scheduledPrefix: cpn
    type: cardano-projected-nft
    startSlot: 22505578
    stopSlot: 32815924
    network: CardanoNetworkConfigEntryName

Meaning

• startSlot is required and means that only events after that slot (exclusive) will be considered. This should be a slot that happened before the first transaction involving the assets.
• stopSlot is optional, and it stops the indexing at that point.

Paima Concise format

The scheduled input for each event is of the following form.

cardanoTransfer = cpn|ownerAddress|previousTxHash|previousOutputIndex|currentTxHash|currentOutputIndex|policyId|assetName|status

Where status is one of:

• Lock
• Unlocking
• Claim
• Invalid

Utility functions

You can get all the projected NFTs for an address with the utility function below

export interface ICdeCardanoGetProjectedNftResult {
  amount: string;
  asset_name: string;
  current_tx_hash: string;
  current_tx_output_index: number | null;
  for_how_long: string | null;
  owner_address: string;
  plutus_datum: string;
  policy_id: string;
  previous_tx_hash: string | null;
  previous_tx_output_index: number | null;
  status: 'Lock' | 'Unlocking' | 'Claim' | 'Invalid';
}

export declare function getCardanoAddressProjectedNfts(
  readonlyDBConn: Pool,
  address: string
): Promise<ICdeCardanoGetProjectedNftResult[]>;