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Create Trust Line and Send Currency Using JavaScript
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Create Trust Line and Send Currency Using JavaScript

This example shows how to:

  1. Configure accounts to allow transfer of funds to third party accounts.
  2. Set a currency type for transactions.
  3. Create a trust line between the standby account and the operational account.
  4. Send issued currency between accounts.
  5. Display account balances for all currencies.

Test harness with currency transfer

You can download the Quickstart Samples archive to try each of the samples in your own browser.

Note
Without the Quickstart Samples, you will not be able to try the examples that follow.

Usage

Open the Token Test Harness and get accounts:

  1. Open 2.create-trustline-send-currency.html in a browser.
  2. 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 Trust Line

To create a trust line between accounts:

  1. Enter a currency code in the Currency field.
  2. Enter the maximum transfer limit in the Amount field.
  3. Enter the destination account value in the Destination field.
  4. Click Create Trustline.

Trust line results

Send an Issued Currency Token

To transfer an issued currency token, once you have created a trust line:

  1. Enter the Amount.
  2. Enter the Destination.
  3. Enter the Currency type.
  4. Click Send Currency.

Currency transfer

Code Walkthrough

You can download the Quickstart Samples archive to try each of the samples in your own browser.

ripplex2-send-currency.js

Configure Account

When transferring fiat currency, the actual transfer of funds is not simultaneous, as it is with XRP. If currency is transferred to a third party for a different currency, there can be a devaluation of the currency that impacts the originating account. To avoid this situation, this up and down valuation of currency, known as rippling, is not allowed by default. Currency transferred from one account can only be transferred back to the same account. To enable currency transfer to third parties, you need to set the rippleDefault value to true. The Token Test Harness provides a checkbox to enable or disable rippling.

// *******************************************************
// **************** Configure Account ********************
// *******************************************************
      
async function configureAccount(type, defaultRippleSetting) {

Connect to the ledger

  let net = getNet()
  let resultField = 'standbyResultField'
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + getNet() + '....'
  await client.connect()
  results += '\nConnected, finding wallet.'

Get the account wallets.

if (type=='standby') {
  my_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
} else {
  my_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  resultField = 'operationalResultField'
}
results += '\nRipple Default Setting: ' + defaultRippleSetting
resultField.value = results

Prepare the transaction. If the rippleDefault argument is true, set the asfDefaultRipple flag. If it is false, clear the asfDefaultRipple flag.

  let settings_tx = {}
  if (defaultRippleSetting) {
    settings_tx = {
      "TransactionType": "AccountSet",
      "Account": my_wallet.address,
      "SetFlag": xrpl.AccountSetAsfFlags.asfDefaultRipple
    } 
    results += '\n Set Default Ripple flag.' 
    } else {
      settings_tx = {
      "TransactionType": "AccountSet",
      "Account": my_wallet.address,
      "ClearFlag": xrpl.AccountSetAsfFlags.asfDefaultRipple
    }
    results += '\n Clear Default Ripple flag.' 
  }
  results += '\nSending account setting.'   
  resultField.value = results

Auto-fill the default values for the transaction.

  const prepared = await client.autofill(settings_tx)

Sign the transaction.

  const signed = my_wallet.sign(prepared)

Submit the transaction and wait for the result.

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

Report the result.

  if (result.result.meta.TransactionResult == "tesSUCCESS") {
    results += '\nAccount setting succeeded.'
    document.getElementById(resultField).value = results
  } else {
    throw 'Error sending transaction: ${result}'
    results += '\nAccount setting failed.'
    resultField.value = results
  }     
  client.disconnect()
} // End of configureAccount()

Create Trust Line

A trust line enables two accounts to trade a defined currency up to a set limit. This gives the participants assurance that any exchanges are between known entities at agreed upon maximum amounts.

// *******************************************************
// ***************** Create TrustLine ********************
// *******************************************************
      
async function createTrustline() {
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + getNet() + '....'
  standbyResultField.value = results

  await client.connect()
  results += '\nConnected.'
  standbyResultField.value = results

Get the standby and operational wallets.

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

Capture the currency code from the standby currency field.

  const currency_code = standbyCurrencyField.value

Define the transaction, capturing the currency code and (limit) amount from the form fields.

  const trustSet_tx = {
    "TransactionType": "TrustSet",
    "Account": standbyDestinationField.value,
    "LimitAmount": {
      "currency": standbyCurrencyField.value,
      "issuer": standby_wallet.address,
      "value": standbyAmountField.value
    }
  }

Prepare the transaction by automatically filling the default parameters.

  const ts_prepared = await client.autofill(trustSet_tx)

Sign the transaction.

  const ts_signed = operational_wallet.sign(ts_prepared)
  results += '\nCreating trust line from operational account to standby account...'
  standbyResultField.value = results

Submit the transaction and wait for the results.

  const ts_result = await client.submitAndWait(ts_signed.tx_blob)

Report the results.

  if (ts_result.result.meta.TransactionResult == "tesSUCCESS") {
    results += '\nTrustline established between account \n' +
      standbyDestinationField.value + ' \n and account\n' + standby_wallet.address + '.'
    standbyResultField.value = results
  } else {
    results += '\nTrustLine failed. See JavaScript console for details.'
    document.getElementById('standbyResultField').value = results     
    throw 'Error sending transaction: ${ts_result.result.meta.TransactionResult}'
  }
} //End of createTrustline()

Send Issued Currency

Once you have created a trust line from an account to your own, you can send issued currency tokens to that account, up to the established limit.

// *******************************************************
// *************** Send Issued Currency ******************
// *******************************************************
      
async function sendCurrency() {

Connect to the ledger.


  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + getNet() + '....'
  document.getElementById('standbyResultField').value = results

  await client.connect()

  results += '\nConnected.'
  standbyResultField.value = results

Get the account wallets.

  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  const currency_code = standbyCurrencyField.value
  const issue_quantity = standbyAmountField.value
        
  const send_token_tx = {
    "TransactionType": "Payment",
    "Account": standby_wallet.address,
    "Amount": {
      "currency": standbyCurrencyField.value,
      "value": standbyAmountField.value,
      "issuer": standby_wallet.address
    },
    "Destination": standbyDestinationField.value
  }

Prepare the transaction by automatically filling default values.

  const pay_prepared = await client.autofill(send_token_tx)

Sign the transaction.

  const pay_signed = standby_wallet.sign(pay_prepared)
  results += 'Sending ${issue_quantity} ${currency_code} to ' +
    standbyDestinationField.value + '...'
  standbyResultField.value = results

Submit the transaction and wait for the results.

  const pay_result = await client.submitAndWait(pay_signed.tx_blob)

Report the results.

  if (pay_result.result.meta.TransactionResult == "tesSUCCESS") {
    results += 'Transaction succeeded: https://testnet.xrpl.org/transactions/${pay_signed.hash}'
    standbyResultField.value = results
  } else {
    results += 'Transaction failed: See JavaScript console for details.'
    standbyResultField.value = results
    throw 'Error sending transaction: ${pay_result.result.meta.TransactionResult}'
  }
  standbyBalanceField.value = (await client.getXrpBalance(standby_wallet.address))
  operationalBalanceField.value = (await client.getXrpBalance(operational_wallet.address))
  getBalances()
  client.disconnect()
} // end of sendCurrency()

Get Balances

// *******************************************************
// ****************** Get Balances ***********************
// *******************************************************

async function getBalances() {

Connect to the ledger.

  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + getNet() + '....'
  standbyResultField.value = results
  await client.connect()   
  results += '\nConnected.'
  standbyResultField.value = results

Get the account wallets.

  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)   
  results = "\nGetting standby account balances...\n"

Define and send the request for the standby account, then wait for the results.

  const standby_balances = await client.request({
    command: "gateway_balances",
    account: standby_wallet.address,
    ledger_index: "validated",
    hotwallet: [operational_wallet.address]
  })

Report the results.

  results += JSON.stringify(standby_balances.result, null, 2)
  standbyResultField.value = results

Define and send the request for the operational account, then wait for the results.

  results += "\nGetting operational account balances...\n"
  const operational_balances = await client.request({
    command: "gateway_balances",
    account: operational_wallet.address,
    ledger_index: "validated"
  })

Report the results.

  results += JSON.stringify(operational_balances.result, null, 2)
  operationalResultField.value = results

Update the form with current XRP balances.

  operationalBalanceField.value = (await client.getXrpBalance(operational_wallet.address))
  standbyResultField.value = results
  standbyBalanceField.value = (await client.getXrpBalance(standby_wallet.address))

Disconnect from the ledger.

  client.disconnect()
} // End of getBalances()

Reciprocal Transactions

For each of the transactions, there is an accompanying reciprocal transaction, with the prefix oP, for the operational account. See the corresponding function for the standby account for code commentary. The getBalances() request does not have a reciprocal transaction, because it reports balances for both accounts.

// *******************************************************
// ************ Create Operational TrustLine *************
// *******************************************************
      
async function oPcreateTrustline() {
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + getNet() + '....'
  operationalResultField.value = results
        
  await client.connect()
  results += '\nConnected.'
  operationalResultField.value = results
          
  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  const trustSet_tx = {
    "TransactionType": "TrustSet",
    "Account": operationalDestinationField.value,
    "LimitAmount": {
      "currency": operationalCurrencyField.value,
      "issuer": operational_wallet.address,
      "value": operationalAmountField.value
    }
  }
  const ts_prepared = await client.autofill(trustSet_tx)
  const ts_signed = standby_wallet.sign(ts_prepared)
  results += '\nCreating trust line from operational account to ' +
   operationalDestinationField.value + ' account...'
  operationalResultField.value = results
  const ts_result = await client.submitAndWait(ts_signed.tx_blob)
  if (ts_result.result.meta.TransactionResult == "tesSUCCESS") {
    results += '\nTrustline established between account \n' + operational_wallet.address +
      ' \n and account\n' + operationalDestinationField.value + '.'
    operationalResultField.value = results
  } else {
    results += '\nTrustLine failed. See JavaScript console for details.'
    operationalResultField.value = results     
    throw 'Error sending transaction: ${ts_result.result.meta.TransactionResult}'
  }
} //End of oPcreateTrustline
      
// *******************************************************
// ************* Operational Send Issued Currency ********
// *******************************************************
      
async function oPsendCurrency() {
  let net = getNet()
  const client = new xrpl.Client(net)
  results = 'Connecting to ' + getNet() + '....'
  operationalResultField.value = results
        
  await client.connect()        
  results += '\nConnected.'
  operationalResultField.value = results
          
  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
  const operational_wallet = xrpl.Wallet.fromSeed(operationalSeedField.value)
  const currency_code = operationalCurrencyField.value
  const issue_quantity = operationalAmountField.value
        
  const send_token_tx = {
    "TransactionType": "Payment",
    "Account": operational_wallet.address,
    "Amount": {
      "currency": currency_code,
      "value": issue_quantity,
      "issuer": operational_wallet.address
    },
    "Destination": operationalDestinationField.value
  }
      
  const pay_prepared = await client.autofill(send_token_tx)
  const pay_signed = operational_wallet.sign(pay_prepared)
  results += 'Sending ${issue_quantity} ${currency_code} to ' +
    operationalDestinationField.value + '...'
  operationalResultField.value = results
  const pay_result = await client.submitAndWait(pay_signed.tx_blob)
  if (pay_result.result.meta.TransactionResult == "tesSUCCESS") {
    results += 'Transaction succeeded: https://testnet.xrpl.org/transactions/${pay_signed.hash}'
    operationalResultField.value = results
  } else {
    results += 'Transaction failed: See JavaScript console for details.'
    operationalResultField.value = results
    throw 'Error sending transaction: ${pay_result.result.meta.TransactionResult}'
  }
  standbyBalanceField.value = (await client.getXrpBalance(standby_wallet.address))
  operationalBalanceField.value = (await client.getXrpBalance(operational_wallet.address))
  getBalances()
  client.disconnect()
} // end of oPsendCurrency()

2.create-trustline-send-currency.html

Update the form to support the new functions.

<html>
  <head>
    <title>Token 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]/build/xrpl-latest-min.js'></script>
    <script src='ripplex1-send-xrp.js'></script>
    <script src='ripplex2-send-currency.js'></script>
    <script>
      if (typeof module !== "undefined") {
        const xrpl = require('xrpl')
      }
    </script>
  </head>
  
<!-- ************************************************************** -->
<!-- ********************** The Form ****************************** -->
<!-- ************************************************************** -->

  <body>
    <h1>Token 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="testnet">Testnet</label>
      &nbsp;&nbsp;
      <input type="radio" id="dn" name="server"
        value="wss://s.devnet.rippletest.net:51233">
      <label for="devnet">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">
                        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>
                    <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
                      </td>
                      <td>
                        <input type="text" id="standbyDestinationField" 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">
                        Currency
                      </td>
                      <td>
                        <input type="text" id="standbyCurrencyField" size="40" value="USD"></input>
                      </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="createTrustline()">Create TrustLine</button>
                        <br/>
                        <button type="button" onClick="sendCurrency()">Send Currency</button>
                        <br/>
                        <button type="button" onClick="getBalances()">Get Balances</button>
                      </td>
                    </tr>
                    </td>
                    </tr>
                  </table>
                </td>
              </tr>
            </table>
          </td>
          <td>
            <table>
              <tr>
                <td>
                <td>
                  <table>
                    <tr>
                      <td align="center" valign="top">
                        <button type="button" onClick="oPsendXRP()">&#60; Send XRP</button>
                        <br/><br/>
                        <button type="button" onClick="oPcreateTrustline()">Create TrustLine</button>
                        <br/>
                        <button type="button" onClick="oPsendCurrency()">Send Currency</button>
                        <br/>
                        <button type="button" onClick="getBalances()">Get Balances</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">
                              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>
                          <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">
                              Destination
                            </td>
                            <td>
                              <input type="text" id="operationalDestinationField" 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">
                              Currency
                            </td>
                            <td>
                              <input type="text" id="operationalCurrencyField" size="40" value="USD"></input>
                            </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>
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