Issue a Token improvements: python, UI fixes, etc.

- Display some errors without marking the step as complete
  (Also applied to Require Destination Tags tutorial)
- Add Python equivalent script

content/_code-samples/issue-a-token/js/issue-a-token.js

@@ -0,0 +1,194 @@
+// Stand-alone code sample for the "issue a token" tutorial:
+// https://xrpl.org/issue-a-fungible-token.html
+
+// Uncomment these dependencies for Node.js. In browsers, use <script> tags as
+// in the example demo.html.
+// const ripple = require('ripple-lib')
+// const fetch = require('node-fetch')
+// const submit_and_verify = require('../submit-and-verify/submit-and-verify.js').submit_and_verify
+
+// Connect ---------------------------------------------------------------------
+async function main() {
+  api = new ripple.RippleAPI({server: 'wss://s.altnet.rippletest.net:51233'})
+  console.log("Connecting to Testnet...")
+  await api.connect()
+
+  // Get credentials from the Testnet Faucet -----------------------------------
+  // This doesn't technically need to happen after you call api.connect() but
+  // it's convenient to do here.
+  async function get_faucet_address() {
+    const faucet_url = "https://faucet.altnet.rippletest.net/accounts"
+    const faucet_options = {
+      method: 'POST',
+      headers: {
+        "Content-Type": "application/json"
+      },
+      body: '{}'
+    }
+    const response = await fetch(faucet_url, faucet_options)
+    if (!response.ok) {
+      throw `Faucet returned an error: ${data.error}`
+    }
+    const data = await response.json()
+    return data
+  }
+
+  console.log("Requesting addresses from the Testnet faucet...")
+  const hot_data = await get_faucet_address()
+  const hot_address = hot_data.account.address
+  const hot_secret = hot_data.account.secret
+
+  const cold_data = await get_faucet_address()
+  const cold_address = cold_data.account.address
+  const cold_secret = cold_data.account.secret
+
+  console.log("Waiting until we have a validated starting sequence number...")
+  // If you go too soon, the funding transaction might slip back a ledger and
+  // then your starting Sequence number will be off. This is mostly relevant
+  // when you want to use a Testnet account right after getting a reply from
+  // the faucet.
+  while (true) {
+    try {
+      await api.request("account_info", {
+        account: cold_address,
+        ledger_index: "validated"
+      })
+      await api.request("account_info", {
+        account: hot_address,
+        ledger_index: "validated"
+      })
+      break
+    } catch(e) {
+      if (e.data.error != 'actNotFound') throw e
+      await new Promise(resolve => setTimeout(resolve, 1000))
+    }
+  }
+  console.log(`Got hot address ${hot_address} and cold address ${cold_address}.`)
+
+  // Configure issuer (cold address) settings ----------------------------------
+  const cold_settings_tx = {
+    "TransactionType": "AccountSet",
+    "Account": cold_address,
+    "TransferRate": 0,
+    "TickSize": 5,
+    "Domain": "6578616D706C652E636F6D", // "example.com"
+    "SetFlag": 8 // enable Default Ripple
+    //"Flags": (api.txFlags.AccountSet.DisallowXRP |
+    //          api.txFlags.AccountSet.RequireDestTag)
+  }
+
+  const cst_prepared = await api.prepareTransaction(
+    cold_settings_tx,
+    {maxLedgerVersionOffset: 10}
+  )
+  const cst_signed = api.sign(cst_prepared.txJSON, cold_secret)
+  // submit_and_verify helper function from:
+  // https://github.com/XRPLF/xrpl-dev-portal/tree/master/content/_code-samples/submit-and-verify/
+  console.log("Sending cold address AccountSet transaction...")
+  const cst_result = await submit_and_verify(api, cst_signed.signedTransaction)
+  if (cst_result == "tesSUCCESS") {
+    console.log(`Transaction succeeded: https://testnet.xrpl.org/transactions/${cst_signed.id}`)
+  } else {
+    throw `Error sending transaction: ${cst_result}`
+  }
+
+
+  // Configure hot address settings --------------------------------------------
+
+  const hot_settings_tx = {
+    "TransactionType": "AccountSet",
+    "Account": hot_address,
+    "Domain": "6578616D706C652E636F6D", // "example.com"
+    "SetFlag": 2 // enable Require Auth so we can't use trust lines that users
+                 // make to the hot address, even by accident.
+    //"Flags": (api.txFlags.AccountSet.DisallowXRP |
+    //          api.txFlags.AccountSet.RequireDestTag)
+  }
+
+  const hst_prepared = await api.prepareTransaction(
+    hot_settings_tx,
+    {maxLedgerVersionOffset: 10}
+  )
+  const hst_signed = api.sign(hst_prepared.txJSON, hot_secret)
+  console.log("Sending hot address AccountSet transaction...")
+  const hst_result = await submit_and_verify(api, hst_signed.signedTransaction)
+  if (hst_result == "tesSUCCESS") {
+    console.log(`Transaction succeeded: https://testnet.xrpl.org/transactions/${hst_signed.id}`)
+  } else {
+    throw `Error sending transaction: ${hst_result}`
+  }
+
+
+  // Create trust line from hot to cold address --------------------------------
+  const currency_code = "FOO"
+  const trust_set_tx = {
+    "TransactionType": "TrustSet",
+    "Account": hot_address,
+    "LimitAmount": {
+      "currency": currency_code,
+      "issuer": cold_address,
+      "value": "10000000000" // Large limit, arbitrarily chosen
+    }
+  }
+
+  const ts_prepared = await api.prepareTransaction(
+    trust_set_tx,
+    {maxLedgerVersionOffset: 10}
+  )
+  const ts_signed = api.sign(ts_prepared.txJSON, hot_secret)
+  console.log("Creating trust line from hot address to issuer...")
+  const ts_result = await submit_and_verify(api, ts_signed.signedTransaction)
+  if (ts_result == "tesSUCCESS") {
+    console.log(`Transaction succeeded: https://testnet.xrpl.org/transactions/${ts_signed.id}`)
+  } else {
+    throw `Error sending transaction: ${ts_result}`
+  }
+
+
+  // Send token ----------------------------------------------------------------
+  const issue_quantity = "3840"
+  const send_token_tx = {
+    "TransactionType": "Payment",
+    "Account": cold_address,
+    "Amount": {
+      "currency": currency_code,
+      "value": issue_quantity,
+      "issuer": cold_address
+    },
+    "Destination": hot_address
+  }
+
+  const pay_prepared = await api.prepareTransaction(
+    send_token_tx,
+    {maxLedgerVersionOffset: 10}
+  )
+  const pay_signed = api.sign(pay_prepared.txJSON, cold_secret)
+  // submit_and_verify helper from _code-samples/submit-and-verify
+  console.log(`Sending ${issue_quantity} ${currency_code} to ${hot_address}...`)
+  const pay_result = await submit_and_verify(api, pay_signed.signedTransaction)
+  if (pay_result == "tesSUCCESS") {
+    console.log(`Transaction succeeded: https://testnet.xrpl.org/transactions/${pay_signed.id}`)
+  } else {
+    throw `Error sending transaction: ${pay_result}`
+  }
+
+  // Check balances ------------------------------------------------------------
+  console.log("Getting hot address balances...")
+  const hot_balances = await api.request("account_lines", {
+    account: hot_address,
+    ledger_index: "validated"
+  })
+  console.log(hot_balances)
+
+  console.log("Getting cold address balances...")
+  const cold_balances = await api.request("gateway_balances", {
+    account: cold_address,
+    ledger_index: "validated",
+    hotwallet: [hot_address]
+  })
+  console.log(JSON.stringify(cold_balances, null, 2))
+
+  api.disconnect()
+} // End of main()
+
+main()