조건부 에스크로 생성하기(Create Conditional Escrows Using JavaScript)

이 페이지에서는 아래 3가지를 배울 수 있습니다:

1. 모든 계정에서 주문 처리 코드(fulfillment code)를 입력하면 사용할 수 있는, 에스크로 결제를 생성합니다.

2. 조건부 에스크로 거래를 완료합니다.

3. 조건부 에스크로 거래를 취소합니다.

전제 조건

Quickstart Samples 이브를 다운로드하여 활용할 수 있습니다.

사용 방법

에스크로 생성(Create Escrow)

조건 코드와 연결된 주문 처리 코드를 사용하여 조건 기반 에스크로를 생성합니다. 다섯 종 조건 애플리케이션을 사용하여 조건/이행 쌍을 생성합니다.

five-bells-condition설치하기:

1. 터미널 창에서, navig로컬의 Quickstart 디렉토리로 이동하기 (편의를 위해)

2. npm install five-bells-condition를 작성하기

Condition/Fulfillment pair 생성하기:

1. 터미널 창에서, navig로컬의 Quickstart 디렉토리로 이동하기 (편의를 위해)

2. node getConditionAndFulfillment.js를 작성하기

3. 생성된 Condition 및 Fulfillment pair를 복사하여 저장하기

Test 계정 만들기:

1. Open 9.escrow-condition.html in a browser

2. 'Testnet' 또는 'Devnet' 선택하기

3. Test 계정들을 가져오기

   1. 만약 기존의 account seeds 를 갖고 있다면,

      1. Seeds field에 account seeds 값을 붙여넣기

      2. 'Get Accounts from Seeds' 클릭하기

   2. 만약 기존의 account seeds 를 갖고 있지 않다면,

      1. 'Get New Standby Account' 클릭하기

      2. 'Get New Operational Account' 클릭하기

조건부 에스크로 생성(Create Conditional Escrow)

조건부 에스크로를 생성할 때는 예약하고자 하는 금액과 위에서 생성한 조건 값을 지정해야 합니다. 에스크로를 더 이상 사용할 수 없는 취소 날짜와 시간을 설정할 수도 있습니다.

조건부 에스크로 생성하기:

1. 전송할 Amount 를 입력하기

2. Operational Account 값을 복사하기

3. Destination Account field 에 붙여넣기

4. Escrow Condition 값을 작성하기

5. Escrow Cancel (seconds) 값을 작성하기

6. 'Create Escrow' 클릭하기

7. Standby Result field 에서 나오는 에스크로 Sequence Number 를 복사하여 저장하기

에스크로는 XRP Ledger instance에 생성되며, 요청하신 XRP 금액에 거래 비용을 더한 금액을 예약합니다.

에스크로를 생성할 때 Sequence Number를 캡처하여 저장하면 에스크로 거래를 완료하는 데 사용할 수 있습니다.

조건부 에스크로 완료(Finish Conditional Escrow)

모든 계정은 에스크로 취소 시간 전에 언제든지 조건부 에스크로를 완료할 수 있습니다. 위의 예에 따라 에스크로 취소 시간이 지나면 시퀀스 번호를 사용하여 거래를 완료할 수 있습니다.

조건부 에스크로 완료하기:

1. Operational account Escrow Sequence Number field에 Sequence number 를 붙여넣기

2. Condition에 대한 Fulfillment 코드를 작성하기

3. Finish Conditional Escrow 클릭하기

거래가 완료되고 Standby 및 Operational accounts, 모두에 대한 잔액이 업데이트됩니다.

에스크로 불러오기(Get Escrows)

Standby account 및 Operational account에 대한 Get Escrows를 클릭하여 현재 에스크로 목록을 확인합니다.

에스크로 취소(Cancel Escrow)

에스크로 취소 시간이 지나면 수취인은 더 이상 에스크로를 사용할 수 없습니다. 에스크로 개시자는 거래 수수료를 제외한 XRP를 회수할 수 있습니다. 취소 시간이 지나면 모든 계정에서 에스크로를 취소할 수 있습니다. 에스크로 취소 시간 전에 거래를 취소하려는 계정에는 명목 거래 비용(12드롭)이 청구되지만 실제 에스크로는 에스크로 취소 시간 이후까지 취소할 수 없습니다.

시퀀스 번호 찾기(Oh No! I Forgot to Save the Sequence Number!)

시퀀스 번호를 저장하는 것을 잊어버린 경우 에스크로 거래 기록에서 찾을 수 있습니다.

1. Create a new escrow as described in Create Escrow, above.

2. Click Get Escrows to get the escrow information.

3. Copy the PreviousTxnID value from the results.

   
4. Paste the PreviousTxnID in the Transaction to Look Up field.

   
5. Click Get Transaction.

6. Locate the Sequence value in the results.

   

실전 예제

이 웹사이트의 소스 리포지토리에서 Quickstart Samples 다운로드할 수 있습니다.

getConditionAndFulfillment.js

To generate a condition/fulfillment pair, use Node.js to run the getConditionAndFulfillment.js script.

function getConditionAndFulfillment() {

Instantiate the five-bells-condition and crypto libraries.

  const cc = require('five-bells-condition')
  const crypto = require('crypto')

Create a random 32-byte seed string.

  const preimageData = crypto.randomBytes(32)

Create a fulfillment object.

  const fulfillment = new cc.PreimageSha256()

Generate a fulfillment code.

  fulfillment.setPreimage(preimageData)

Generate the condition value based on the fulfillment value.

  const condition = fulfillment.getConditionBinary().toString('hex').toUpperCase()

Return the condition.

  console.log('Condition:', condition)

Convert the fulfillment code to a hexadecimal string.

  const fulfillment_hex = fulfillment.serializeBinary().toString('hex').toUpperCase()

Return the fulfillment code. Keep it secret until you want to finish the escrow.

  console.log('Fulfillment:', fulfillment_hex)
}
getConditionAndFulfillment()

ripplex9-escrow-condition.js

Create Conditional Escrow

async function createConditionalEscrow() {

Connect to your preferred ledger.

  results  = "Connecting to the selected ledger.\n"
  standbyResultField.value = results
  let net = getNet()
  results = "Connecting to " + net + "....\n"
  const client = new xrpl.Client(net)
  await client.connect()

  results  += "Connected. Creating conditional escrow.\n"
  standbyResultField.value = results

Instantiate the standby and operational wallets

  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)

Capture the amount to send in the escrow.

  const sendAmount = standbyAmountField.value

Update the results field.

  results += "\nstandby_wallet.address: = " + standby_wallet.address
  standbyResultField.value = results

Create a date value and add your requested number of seconds.

  let escrow_cancel_date = new Date()
  escrow_cancel_date = addSeconds(parseInt(standbyEscrowCancelDateField.value))

Prepare the EscrowCreate transaction.

  const escrowTx = await client.autofill({
    "TransactionType": "EscrowCreate",
    "Account": standby_wallet.address,
    "Amount": xrpl.xrpToDrops(sendAmount),
    "Destination": standbyDestinationField.value,
    "CancelAfter": escrow_cancel_date,
    "Condition": standbyEscrowConditionField.value
  })

Sign the transaction.

  const signed = standby_wallet.sign(escrowTx)

Submit the transaction and wait for the results.

  const tx = await client.submitAndWait(signed.tx_blob)

Report the results and update balance fields.

  results += "\nSequence Number (Save!): " + JSON.stringify(tx.result.Sequence)
  results  += "\n\nBalance changes: " + 
  JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  standbyBalanceField.value = (await client.getXrpBalance(standby_wallet.address))
  operationalBalanceField.value = (await client.getXrpBalance(operational_wallet.address))
  standbyResultField.value = results

Disconnect from the XRPL

client.disconnect()

} // End of createTimeEscrow()

Finish Conditional Escrow

Finish the escrow by submitting the condition and fulfillment codes.

async function finishConditionalEscrow() {

Connect to your preferred XRP Ledger instance.

  results  = "Connecting to the selected ledger.\n"
  operationalResultField.value = results
  let net = getNet()
  results += 'Connecting to ' + getNet() + '....'
  const client = new xrpl.Client(net)
  await client.connect()
  results  += "\nConnected. Finishing escrow.\n"
  operationalResultField.value = results

Get the standby and operational account wallets.

  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const sendAmount = operationalAmountField.value

  results += "\noperational_wallet.address: = " + operational_wallet.address
  operationalResultField.value = results

Prepare the transaction.

  const prepared = await client.autofill({
    "TransactionType": "EscrowFinish",
    "Account": operationalAccountField.value,
    "Owner": standbyAccountField.value,
    "OfferSequence": parseInt(operationalEscrowSequenceField.value),
    "Condition": standbyEscrowConditionField.value,
    "Fulfillment": operationalFulfillmentField.value
  })

Sign the transaction.

  const signed = operational_wallet.sign(prepared)

Submit the transaction and wait for the results.

  const tx = await client.submitAndWait(signed.tx_blob)

Report the results.

  results  += "\nBalance changes: " + 
    JSON.stringify(xrpl.getBalanceChanges(tx.result.meta), null, 2)
  operationalResultField.value = results
  standbyBalanceField.value = (await client.getXrpBalance(standby_wallet.address))
  operationalBalanceField.value = (await client.getXrpBalance(operational_wallet.address))

Disconnect from the XRPL.

  client.disconnect()

} // End of finishEscrow()

9.escrow-condition.html

<html>
  <head>
    <title>Conditional Escrow Test Harness</title>
    <link href='https://fonts.googleapis.com/css?family=Work Sans' rel='stylesheet'>
    <style>
       body{font-family: "Work Sans", sans-serif;padding: 20px;background: #fafafa;}
       h1{font-weight: bold;}
       input, button {padding: 6px;margin-bottom: 8px;}
       button{font-weight: bold;font-family: "Work Sans", sans-serif;}
       td{vertical-align: middle;}
    </style>    
    <script src='https://unpkg.com/xrpl@2.2.3'></script>
    <script src='ripplex1-send-xrp.js'></script>
    <script src='ripplex2-send-currency.js'></script>
    <script src='ripplex8-escrow.js'></script>
    <script src='ripplex9-escrow-condition.js'></script>
  </head>

<!-- ************************************************************** -->
<!-- ********************** The Form ****************************** -->
<!-- ************************************************************** -->

  <body>
    <h1>Conditional Escrow Test Harness</h1>
    <form id="theForm">
      Choose your ledger instance:  
      &nbsp;&nbsp;
      <input type="radio" id="tn" name="server"
        value="wss://s.altnet.rippletest.net:51233" checked>
      <label for="tn">Testnet</label>
      &nbsp;&nbsp;
      <input type="radio" id="dn" name="server"
        value="wss://s.devnet.rippletest.net:51233">
      <label for="dn">Devnet</label>
      <br/><br/>
      <button type="button" onClick="getAccountsFromSeeds()">Get Accounts From Seeds</button>
      <br/>
      <textarea id="seeds" cols="40" rows= "2"></textarea>
      <br/><br/>
      <table>
        <tr valign="top">
          <td>
            <table>
              <tr valign="top">
                <td>
                <td>
                  <button type="button" onClick="getAccount('standby')">Get New Standby Account</button>
                  <table>
                    <tr valign="top">
                      <td align="right">
                        Standby Account
                      </td>
                      <td>
                        <input type="text" id="standbyAccountField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        XRP Balance
                      </td>
                      <td>
                        <input type="text" id="standbyBalanceField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Amount
                      </td>
                      <td>
                        <input type="text" id="standbyAmountField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Destination Account
                      </td>
                      <td>
                        <input type="text" id="standbyDestinationField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Escrow Condition
                      </td>
                      <td>
                        <input type="text" id="standbyEscrowConditionField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Escrow Cancel (seconds)
                      </td>
                      <td>
                        <input type="text" id="standbyEscrowCancelDateField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Escrow Sequence Number
                      </td>
                      <td>
                        <input type="text" id="standbyEscrowSequenceNumberField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr valign="top">
                      <td><button type="button" onClick="configureAccount('standby',document.querySelector('#standbyDefault').checked)">Configure Account</button></td>
                      <td>
                        <input type="checkbox" id="standbyDefault" checked="true"/>
                        <label for="standbyDefault">Allow Rippling</label>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Public Key
                      </td>
                      <td>
                        <input type="text" id="standbyPubKeyField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Private Key
                      </td>
                      <td>
                        <input type="text" id="standbyPrivKeyField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                    <tr>
                      <td align="right">
                        Seed
                      </td>
                      <td>
                        <input type="text" id="standbySeedField" size="40"></input>
                        <br>
                      </td>
                    </tr>
                  </table>
                  <p align="left">
                    <textarea id="standbyResultField" cols="80" rows="20" ></textarea>
                  </p>
                </td>
                </td>
                <td>
                  <table>
                    <tr valign="top">
                      <td align="center" valign="top">
                        <button type="button" onClick="sendXRP()">Send XRP &#62;</button>
                        <br/><br/>
                        <button type="button" onClick="getBalances()">Get Balances</button>       
                        <br/>
                        <button type="button" onClick="createConditionalEscrow()">Create Conditional Escrow</button>
                        <br/>
                        <button type="button" onClick="getStandbyEscrows()">Get Escrows</button>
                        <br/>
                        <button type="button" onClick="cancelEscrow()">Cancel Escrow</button>
                      </td>
                      </td>
                    </tr>
                    </td>
                    </tr>
                  </table>
                </td>
              </tr>
            </table>
          </td>
          <td>
            <table>
              <tr>
                <td>
                <td>
                  <table>
                    <tr valign="top">
                      <td align="center" valign="top">
                        <button type="button" onClick="oPsendXRP()">&#60; Send XRP</button>
                        <br/><br/>
                        <button type="button" onClick="getBalances()">Get Balances</button>
                        <br/>
                        <button type="button" onClick="finishConditionalEscrow()">Finish Conditional Escrow</button>
                        <br/>
                        <button type="button" onClick="getOperationalEscrows()">Get Escrows</button>
                        <br/>
                        <button type="button" onClick="getTransaction()">Get Transaction</button>
                      </td>
                      <td valign="top" align="right">
                        <button type="button" onClick="getAccount('operational')">Get New Operational Account</button>
                        <table>
                          <tr valign="top">
                            <td align="right">
                              Operational Account
                            </td>
                            <td>
                              <input type="text" id="operationalAccountField" size="40"></input>
                              <br>
                            </td>
                          </tr>

                          <tr>
                            <td align="right">
                              XRP Balance
                            </td>
                            <td>
                              <input type="text" id="operationalBalanceField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Amount
                            </td>
                            <td>
                              <input type="text" id="operationalAmountField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Fulfillment Code
                            </td>
                            <td>
                              <input type="text" id="operationalFulfillmentField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                          <tr>
                            <td align="right">
                              Escrow Sequence Number
                            </td>
                            <td>
                              <input type="text" id="operationalEscrowSequenceField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Transaction to Look Up
                            </td>
                            <td>
                              <input type="text" id="operationalTransactionField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                          <td>
                            </td>
                            <td align="right">
                            <input type="checkbox" id="operationalDefault" checked="true"/>
                              <label for="operationalDefault">Allow Rippling</label>
                              <button type="button" onClick="configureAccount('operational',document.querySelector('#operationalDefault').checked)">Configure Account</button>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Public Key
                            </td>
                            <td>
                              <input type="text" id="operationalPubKeyField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Private Key
                            </td>
                            <td>
                              <input type="text" id="operationalPrivKeyField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                          <tr>
                            <td align="right">
                              Seed
                            </td>
                            <td>
                              <input type="text" id="operationalSeedField" size="40"></input>
                              <br>
                            </td>
                          </tr>
                        </table>
                        <p align="right">
                          <textarea id="operationalResultField" cols="80" rows="20" ></textarea>
                        </p>
                      </td>
                      </td>
                    </tr>
                    </td>
                    </tr>
                  </table>
                </td>
              </tr>
            </table>
          </td>
        </tr>
      </table>
    </form>
  </body>
</html>