pact-lang - 如何创建一个 KDA 钱包防护，允许任意数量的人在满足特定条件的情况下从中提款？

Question

问题:如何创建一个钱包保护程序，允许任意数量的人在满足特定条件的情况下从中提款？

我正在尝试制作一个带有保护装置的钱包，让用户根据他们拥有 NFT 的时间等因素，从钱包中提取特定金额。现在我正在做最基本的检查:查看传递到声明函数的“接收者”地址是否是特定 NFT 的所有者。如果他们拥有该 NFT，他们可以想提取多少就提取多少。

   (defcap WITHDRAW (recipient:string nft-id:string)
        (with-read mledger nft-id
            {'owner-address := owner-address }
            (enforce (= recipient owner-address) "not the owner of this NFT")
        )
        (compose-capability (BANK_DEBIT))
    )

    (defun require-WITHDRAW (recipient:string nft-id:string) 
        (require-capability (WITHDRAW recipient nft-id))
    )

    (defun create-WITHDRAW-guard (recipient:string nft-id:string)
        (create-user-guard (require-WITHDRAW recipient nft-id))
    )

    (defun create-simple-user-guard (funder:string nft-id:string BANK_KDA_ACCT:string amount:decimal recipient:string)
        (coin.transfer-create funder BANK_KDA_ACCT 
          (create-WITHDRAW-guard recipient nft-id) amount)
    )

使用我当前的代码，只有我传入的第一个输入 (create-simple-user-guard) 会影响谁可以撤回，但我不知道如何允许守卫接受许多不同的收件人和 NFT-id 。任何建议将不胜感激。

我正在关注这个“教程”https://medium.com/kadena-io/deprecation-notice-for-module-guards-and-pact-guards-2efbf64f488f但在实现更强大的借记功能后，它会丢失任何数量的细节

Answer 1

假设您的 nft-id 可以引用一个集合，而不仅仅是一个单独的 NFT，则此代码应该允许任何拥有该集合的个人从合约中索取某些内容。

(defcap WITHDRAW (nft-id:string)
  (with-read mledger nft-id
      {'owner-address := owner-address }
      (enforce (= (read-msg "recipient") owner-address) "not the owner of this NFT")
  )
  (compose-capability (BANK_DEBIT))
)

(defun require-WITHDRAW (nft-id:string) 
  (require-capability (WITHDRAW nft-id))
)

(defun create-WITHDRAW-guard (nft-id:string)
  (create-user-guard (require-WITHDRAW nft-id))
)

(defun create-simple-user-guard (funder:string nft-id:string BANK_KDA_ACCT:string amount:decimal)
  (coin.transfer-create funder BANK_KDA_ACCT 
    (create-WITHDRAW-guard nft-id) amount)
)

请记住，此代码要求您以这种方式将recipient传递到交易的环境数据中:

{ "recipient": "k:abcd..." }

希望这有帮助!