Question

我有情景：

NodeA向NodeB发送状态（State：value = 100，CustomerFlag = 0 ）
NodeB检查状态/值并发送已批准的标志签名。（州：值= 100，CustomerFlag = 1 ）

你可以帮我看看如何在NodeB响应批准/拒绝时添加该值吗？

发起人类：

    @Suspendable
    override fun call(): SignedTransaction {

        val notary = serviceHub.networkMapCache.notaryIdentities[0]

        val iouState = IOUState(iouValue, serviceHub.myInfo.legalIdentities.first(), otherParty)
        val txCommand = Command(IOUContract.Commands.Create(), iouState.participants.map { it.owningKey })
        val txBuilder = TransactionBuilder(notary).withItems(StateAndContract(iouState, IOU_CONTRACT_ID), txCommand)

        txBuilder.verify(serviceHub)
        otherPartyFlow.send(partSignedTx)
        val partSignedTx = serviceHub.signInitialTransaction(txBuilder)
        val otherPartyFlow = initiateFlow(otherParty)
        otherPartyFlow.send(partSignedTx)
        return partSignedTx
    }
}

接受者类：

@InitiatedBy(Initiator::class)
class Acceptor(val otherPartyFlow: FlowSession) : FlowLogic<SignedTransaction>() {
    @Suspendable
    override fun call(): SignedTransaction {

        val receivedData = otherPartyFlow.receive<SignedTransaction>()

        receivedData.unwrap {data -> data }
<<<<< Need help here how to add value and send back >>>>
return updatedData
}
}

Answer 1

您可能需要稍微重新考虑一下您的流程才能使其正常运行。我想说你最好的选择不是将签署的交易发送给接受者，而是发送IOU状态。然后，Acceptor类可以在状态中更改此标志，并创建/签署事务。然后可以将其发送回启动器类，以验证标志是否已更改，签署事务，然后将其提交到分类帐。

@Suspendable
override fun call(): SignedTransaction {

    val iouState = IOUState(iouValue, serviceHub.myInfo.legalIdentities.first(), otherParty)

    val otherPartyFlow = initiateFlow(otherParty)
    otherPartyFlow.send(iouState)

    //Receieve back the signedTransaction
    val ptx = otherPartyFlow.receive<SignedTransaction>().unwrap{it}
    val stx = serviceHub.addSignature(ptx)
    //Resolve and commit to the ledger
    subFlow(ResolveTransactionsFlow(stx, otherPartyFlow))
    return subFlow(FinalityFlow(stx))
    }
}

@InitiatedBy(Initiator::class)
class Acceptor(val otherPartyFlow: FlowSession) : FlowLogic<SignedTransaction>() {
    @Suspendable
    override fun call(): SignedTransaction {
        val notary = serviceHub.networkMapCache.notaryIdentities[0]
        val receivedData = otherPartyFlow.receive<IOUState>().unwrap{
            //Do any state verification here
            it
        }
        receivedData.customerFlag = 1

       //Create the txn
       val txCommand = Command(IOUContract.Commands.Create(), receivedData.participants.map { it.owningKey })
       val txBuilder = TransactionBuilder(notary).withItems(StateAndContract(receivedData, IOU_CONTRACT_ID), txCommand)
       //Sign the transaction
       val partSignedTx = serviceHub.signInitialTransaction(txBuilder)
       otherPartyFlow.send(partSignedTx)
       return waitForLedgerCommit(partSignedTx.id)
}
}

您还可以考虑使用signTransactionsFlow来收集签名，而不是像上面所做的那样来回发送stx - 请参阅https://docs.corda.net/flow-state-machines.html

Answer 2

我创建了2个独立的流客户端和客户。

客户流程1：创建状态，将批准标志设置为0并提交到分类帐。

subFlow(FinalityFlow(fullySignedTx, FINALISING_TRANSACTION.childProgressTracker()))
客户流程2：
- 提取客户提交的状态，并将该状态用作客户流的输入。 val criteria = QueryCriteria.VaultQueryCriteria(status = Vault.StateStatus.UNCONSUMED) val results = serviceHub.vaultService.queryBy<POCState>(criteria) val pocState = results.states.last().state.data
- 重置审批标志= 1并提交分类帐。
val ourOtherOutputState: POCState = pocState.copy(stateCode = pocStateCode)
- 构建交易并提交到分类帐。
val txCommand = Command(BankContract.Commands.Create(), pocState.participants.map { it.owningKey }) val txBuilder = TransactionBuilder(notary).withItems(StateAndContract(ourOtherOutputState, POC_CONTRACT_ID), txCommand) val partSignedTx = serviceHub.signInitialTransaction(txBuilder) val fullySignedTx = subFlow(CollectSignaturesFlow(partSignedTx, setOf(otherPartyFlow), GATHERING_SIGS.childProgressTracker())) return subFlow(FinalityFlow(fullySignedTx, FINALISING_TRANSACTION.childProgressTracker()))

感谢@Raymond Mogg的支持！

接受者如何为州增值并发送回发起人

2 个答案: