javascript - 如何在 Hyperledger Composer 中查找特定 Assets 和参与者的交易是否已经存在？

Question

Participant 
IDFC 

Participant
TATA , MRF 

Asset
FINANCEPROGRAM 

Transaction
(Data need to submit)
participant(TATA) ,Asset (FINANCEPROGRAM ) ,loanAmount , loantenure

我需要检查FINANCEPROGRAM和TATA的交易是否已经存在。

如果存在，我需要拒绝交易。

var query1 = query('SELECT com.ett.blockchain.Programmeben WHERE (beneficiary == _$beneficiary AND bankprogramme == _$bank program) ');

 return  query('query1',{beneficiary : 'resource:com.ett.blockchain.Beneficiary #'+pgben.beneficiary .customerid,bankprogram: 'resource:com.ett.blockchain.Bankprogramme#'+pgben.bankprogramme.programmeid})

  .then(function (transactions1) {

   transactions1.forEach(function (trans1) {    

       console.log("transaction exist " );

        });

    throw Error("Transaction already exist");

});

Answer 1

您缺少 buildQuery 语句。

例如

var query1 = buildQuery('SELECT com.ett.blockchain.Programmeben WHERE (beneficiary == _$beneficiary AND bankprogramme == _$bank program) ');

return query(query1, { beneficiary : 'resource:com.ett.blockchain.Beneficiary#' + pgben.beneficiary.customerid, bankprogram: 'resource:com.ett.blockchain.Bankprogramme#' + pgben.bankprogramme.programmeid } )

请参阅此处的示例(特别是“Javascript 代码 js”部分)-> Why are the following added assets not persisted in the hyperledger registry?