Create Conditional Escrows Using JavaScript

This example shows how to:

Create escrow payments that become available when any account enters a fulfillment code.
Complete a conditional escrow transaction.
Cancel a conditional escrow transaction.

Prerequisites

Download and expand the Quickstart Samples archive.

Usage

Create Escrow

You create a condition-based escrow using a fulfillment code associated with a condition code. Create the condition/fulfillment pair using the five-bells-condition application.

Install five-bells-condition:

In a terminal window, navigate to your local Quickstart directory (for convenience).
Enter the command npm install five-bells-condition.

To create a condition/fulfillment pair:

In a terminal window, navigate to your Quickstart directory.
Enter the command node getConditionAndFulfillment.js.
Copy and save the generated Condition and Fulfillment pair.

To get test accounts:

Open 9.escrow-condition.html in a browser
Choose Testnet or Devnet.
Get test accounts.
1. If you have existing account seeds
  1. Paste account seeds in the Seeds field.
  2. Click Get Accounts from Seeds.
2. If you do not have account seeds:
  1. Click Get New Standby Account.
  2. Click Get New Operational Account.

Create Conditional Escrow:

When you create a conditional escrow, you need to specify the amount you want to reserve and the Condition value you generated above. You can also set a cancel date and time, after which the escrow is no longer available.

To create a conditional escrow:

Enter an Amount to transfer.
Copy the Operational Account value.
Paste it in the Destination Account field.
Enter the Escrow Condition value.
Enter the Escrow Cancel (seconds) value.
Click Create Escrow.
Copy and save the Sequence Number of the escrow called out in the Standby Result field.

The escrow is created on the XRP Ledger instance, reserving your requested XRP amount plus the transaction cost.

When you create an escrow, capture and save the Sequence Number so that you can use it to finish the escrow transaction.

Finish Conditional Escrow

Any account can finish the conditional escrow any time before the Escrow Cancel time. Following on the example above, you can use the Sequence Number to finish the transaction once the Escrow Cancel time has passed.

To finish a time-based escrow:

Paste the sequence number in the Operational account Escrow Sequence Number field.
Enter the Fulfillment code for the Condition.
Click Finish Conditional Escrow.

The transaction completes and balances are updated for both the Standby and Operational accounts.

Get Escrows

Click Get Escrows for either the Standby account or the Operational account to see their current list of escrows.

Cancel Escrow

When the Escrow Cancel time passes, the escrow is no longer available to the recipient. The initiator of the escrow can reclaim the XRP, less the transaction fees. Any account can cancel an escrow once the cancel time has elapsed. Accounts that try to cancel the transaction prior to the Escrow Cancel time are charged the nominal transaction cost (12 drops), but the actual escrow cannot be cancelled until after the Escrow Cancel time.

Oh No! I Forgot to Save the Sequence Number!

If you forget to save the sequence number, you can find it in the escrow transaction record.

Create a new escrow as described in Create Escrow, above.
Click Get Escrows to get the escrow information.
Copy the PreviousTxnID value from the results.
Paste the PreviousTxnID in the Transaction to Look Up field.
Click Get Transaction.
Locate the Sequence value in the results.

Code Walkthrough

You can download the Quickstart Samplesin the source repository for this website.

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/[email protected]'></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>