Hyperledger Composer 检查数组

Question

我在我的 model.cto 文件中定义了一个数组 Account[] family，我想从我的 logic.js 访问它。特别是我只想在接收方在发送方的家庭数组中时才执行交易。

我的model.cto:

namespace org.digitalpayment

asset Account identified by accountId {
  o String accountId
  --> Customer owner
  o Double balance
}

participant Customer identified by customerId {
  o String customerId
  o String firstname
  o String lastname
  --> Account[] family optional
}

transaction AccountTransfer {
--> Account from
--> Account to
o Double amount
}

我的logic.js:

/**
* Account transaction
* @param {org.digitalpayment.AccountTransfer} accountTransfer
* @transaction
*/
async function accountTransfer(accountTransfer) {
    if (accountTransfer.from.balance < accountTransfer.amount) {
        throw new Error("Insufficient funds");
    }

    if (/*TODO check if the family array contains the receiver account*/) {        

        // perform transaction
        accountTransfer.from.balance -= accountTransfer.amount;
        accountTransfer.to.balance += accountTransfer.amount;

        let assetRegistry = await getAssetRegistry('org.digitalpayment.Account');

        await assetRegistry.update(accountTransfer.from);
        await assetRegistry.update(accountTransfer.to);

    } else {
        throw new Error("Receiver is not part of the family");
    }

}

Answer 1

好吧，基本上你想先获取 Family 资产的所有账户，然后检查 Customer 参与者是否包含在其中？如果我错了，请纠正我。 一组合乎逻辑的步骤是 -

1. 根据 to 和 from 输入检索 Account
2. 使用 owner 变量
为每个 Account 检索每个 Customer
3. 从每个 Customer
中获取 family 变量

/**
* Account transaction
* @param {org.digitalpayment.AccountTransfer} accountTransfer
* @transaction
*/
async function accountTransfer(accountTransfer) {
    if (accountTransfer.from.balance < accountTransfer.amount) {
        throw new Error("Insufficient funds");
    };

    var from = accountTransfer.from;
    var to = accountTransfer.to;
    var fromCustomer = from.owner;
    var toCustomer = to.owner;
    var fromCustomerFamily = fromCustomer.family;

    if (fromCustomerFamily && fromCustomerFamily.includes(to)) {        

        // perform transaction
        accountTransfer.from.balance -= accountTransfer.amount;
        accountTransfer.to.balance += accountTransfer.amount;

        let assetRegistry = await getAssetRegistry('org.digitalpayment.Account');

        await assetRegistry.update(accountTransfer.from);
        await assetRegistry.update(accountTransfer.to);

    } else {
        throw new Error("Receiver is not part of the family");
    }

}

由于最近几个 Composer 版本中的语法更改可能无法正常工作，具体取决于您在项目中使用的版本。如果这不起作用并且您使用的是旧版本，请告诉我，我会相应地更新答案。