为什么我在 Corda 中收到 initiator of CollectSignaturesFlow must pass in exact sessions 错误？

Question

我正在制作一个涉及两方的 CorDapp——客户和承销商。我有两个主要流程，一个是 IssuePolicy，另一个是 PayoutPolicy。当我运行每个流量一次时，没有问题。当我再次运行 IssuePolicy 时，我收到错误消息：The Initiator of CollectSignaturesFlow must pass in exactly the sessions required to sign the transaction. 我已经搜索了 Stack Overflow 并找到了这个 post: 但我相信我已经与一方签约并与对方一起发起了流程，所以我不确定这个解决方案是否适用于我。如有任何帮助，我们将不胜感激！

问题政策流程：

        // Step 3. Building.
        progressTracker.currentStep = BUILDING
        val notary = serviceHub.networkMapCache.notaryIdentities[0]
        val utx = TransactionBuilder(notary = notary)
                .addOutputState(policy, INSUREFLIGHT_CONTRACT_ID)
                .addCommand(InsureFlightContract.Commands.Issue(), policy.participants.map { it.owningKey })
                .setTimeWindow(serviceHub.clock.instant(), 30.seconds)

        // Stage 4. Get some cash from the vault and add a spend to our transaction builder.
        // We pay cash to the underwriter's policy key.
        val (_, cashSigningKeys) = Cash.generateSpend(serviceHub, utx, premium, underwriter)
        check(cashSigningKeys == cashSigningKeys){
            throw FlowException("")
        }
        // Step 5. Sign the transaction.
        progressTracker.currentStep = SIGNING
        val ptx = serviceHub.signInitialTransaction(utx, policy.client.owningKey)

        // Step 6. Get the counter-party signature.
        progressTracker.currentStep = COLLECTING
        val otherpartySession = initiateFlow(underwriter)
        val stx = subFlow(CollectSignaturesFlow(
                ptx,
                listOf(otherpartySession),
                COLLECTING.childProgressTracker())
        )

        // Step 7. Finalize the transaction.
        progressTracker.currentStep = FINALIZING
        return subFlow(FinalityFlow(stx, FINALIZING.childProgressTracker()))
    }
}

// Allows counterparty to respond.
@InitiatedBy(Initiator::class)
class IssuePolicyResponder(val otherPartySession: FlowSession) : FlowLogic<Unit>() {
@Suspendable
override fun call() {
    val signTransactionFlow = object : SignTransactionFlow(otherPartySession, SignTransactionFlow.tracker()) {
        override fun checkTransaction(stx: SignedTransaction) = requireThat {
        }
    }

    subFlow(signTransactionFlow)
}
}
}

政策状态定义：

//Policy Class, includes premium, claim, client, underwriter, flight, and policyID
data class Policy(val premium: Amount<Currency>,
              val claim: Amount<Currency>,
              val client: Party,
              val underwriter: Party,
              val flight: String,
              override val linearId: UniqueIdentifier = UniqueIdentifier()) : LinearState {

//Get clients and underwriters
override val participants: List<Party> get() = listOf(client, underwriter)

//Functions to update policy parameters
fun payPremium(amountToPay: Amount<Currency>) = copy(premium = premium + amountToPay)
fun payClaim(amountToPay: Amount<Currency>) = copy(claim = claim + amountToPay)
fun withNewClient(newClient: Party) = copy(client = newClient)
fun withNewUnderwriter(newUnderwriter: Party) = copy(underwriter = newUnderwriter)
fun withNewFlight(newFlight: String) = copy(flight = newFlight)

//Provides response
override fun toString(): String {
    val clientString = (client as? Party)?.name?.organisation ?: client.owningKey.toBase58String()
    val underwriterString = (underwriter as? Party)?.name?.organisation ?: underwriter.owningKey.toBase58String()
    return "Policy($linearId): $clientString has paid a premium of $$premium for flight $flight, underwritten by $underwriterString with" +
            "a claim amount of $$claim."
}
}

合约中的命令：

interface Commands : CommandData {
    class Issue : TypeOnlyCommandData(), Commands
    class Settle : TypeOnlyCommandData(), Commands
}

override fun verify(tx: LedgerTransaction): Unit {
    val command = tx.commands.requireSingleCommand<Commands>()
    val setOfSigners = command.signers.toSet()
    when (command.value) {
        is Commands.Issue -> verifyIssue(tx, setOfSigners)
        is Commands.Settle -> verifySettle(tx, setOfSigners)
        else -> throw IllegalArgumentException("Unrecognized command. You can only issue or settle.")
    }
}

Answer 1

并非节点保险库中的所有现金都由节点的主 public 密钥拥有。这是因为当 Cash.generateSpend 生成更改输出时，出于隐私原因，此更改将分配给新的机密身份而不是您节点的主要身份。

这是 Cash.generateSpend 返回的 cashSigningKeys 的目的。这是 public 键的列表，这些键拥有 Cash.generateSpend 添加到交易生成器的所有现金。

我猜你第一次运行 IssuePolicy/PayoutPolicy 时，它会产生一些由新机密身份拥有的现金。您永远不会使用新机密身份的密钥签署交易。实际上，当您调用 CollectSignaturesFlow.

时，丢失的正是这个机密身份的会话

当然，用这个机密身份创建会话没有意义，因为它实际上对应于运行ning 流的节点。相反，您需要获取 Cash.generateSpend 返回的 cashSigningKeys，并在调用 CollectSignaturesFlow 之前使用这些签署交易，方法是调用：

val ptx = serviceHub.signInitialTransaction(
    utx, 
    cashSigningKeys + policy.client.owningKey)

为什么我在 Corda 中收到 initiator of CollectSignaturesFlow must pass in exact sessions 错误？

Why do I get initiator of CollectSignaturesFlow must pass in exact sessions error in Corda?

corda