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xrpl-dev-portal/_code-samples/submit-and-verify/js/submit-and-verify2.js

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JavaScript

// Submit-and-verify XRPL transaction using xrpl.js (v2.0)
// Demonstrates how to submit a transaction and wait for validation.
// This is not true "robust" transaction submission because it does not protect
// against power outages or other sudden interruptions.
// It may be more robust than the submitAndWait() method included in xrpl.js 2.0
// because it uses subscriptions and checks the server's available ledger range.
// Look up a transaction's result.
// Arguments:
// @param api object Client instance connected to the network where you
// submitted the transaction. MUST ALREADY BE SUBSCRIBED TO THE
// `ledger` event stream.
// @param tx_id string The identifying hash of the transaction.
// @param max_ledger int optional The highest ledger index where the
// transaction can be validated.
// @param min_ledger int optional The lowest ledger index where the
// transaction can be validated.
// Returns: Promise<object> -> result of the tx command with the transaction's
// validated transaction results.
// On failure, the reason is an object with two fields:
// - failure_final: if true, this transaction did not achieve consensus and
// it can never be validated in the future (assuming the
// min_ledger and max_ledger values provided were accurate).
// - msg: A human-readable message explaining what happened.
function lookup_tx_final(api, tx_id, max_ledger, min_ledger) {
if (typeof min_ledger == "undefined") {
min_ledger = -1
}
if (typeof max_ledger == "undefined") {
max_ledger = -1
}
if (min_ledger > max_ledger) {
// Assume the args were just passed backwards & swap them
[min_ledger, max_ledger] = [max_ledger, min_ledger]
}
// Helper to determine if we (should) know the transaction's final result yet.
// If the server has validated all ledgers the tx could possibly appear in,
// then we should know its final result.
async function server_has_ledger_range(min_ledger, max_ledger) {
const si = await api.request({command: "server_info"})
// console.log(`Server has ledger range: ${si.result.info.complete_ledgers}`)
if (si.result.info.complete_ledgers == "empty") {
console.warn("Connected server is not synced.")
return false
}
// In case of a discontiguous set, use only the last set, since we need
// continuous history from submission to expiration to know that a
// transaction failed to achieve consensus.
const ledger_ranges = si.result.info.complete_ledgers.split(',')
// Note: last_range can be in the form 'x-y' or just 'y'
const last_range = ledger_ranges[ledger_ranges.length -1].split('-')
const lr_min = parseInt(last_range[0])
const lr_max = parseInt(last_range[last_range.length - 1])
if (lr_min <= min_ledger && lr_max >= max_ledger) {
// Server has ledger range needed.
return true
}
return false
}
return new Promise((resolve, reject) => {
ledger_listener = async (ledger) => {
try {
const tx_response = await api.request({
"command": "tx",
"transaction": tx_id,
"min_ledger": min_ledger,
"max_ledger": max_ledger
})
if (tx_response.result.validated) {
resolve(tx_response.result.meta.TransactionResult)
} else if (ledger.ledger_index >= max_ledger) {
api.off("ledgerClosed", ledger_listener)
// Transaction found, not validated, but we should have a final result
// by now.
// Work around https://github.com/ripple/rippled/issues/3727
if (await server_has_ledger_range(min_ledger, max_ledger)) {
// Transaction should have been validated by now.
reject({
failure_final: true,
msg: `Transaction not found in ledgers ${min_ledger}-${max_ledger}. This result is final if this range is correct.`
})
} else {
reject({
failure_final: false,
msg: "Can't get final result (1). Check a full history server."
})
}
} else {
// Transaction may still be validated later. Keep waiting.
}
} catch(e) {
console.warn(e)
if (e.data.error == "txnNotFound") {
if (e.data.searched_all) {
api.off("ledgerClosed", ledger_listener)
reject({
failure_final: true,
msg: `Transaction not found in ledgers ${min_ledger}-${max_ledger}. This result is final if this range is correct.`
})
} else {
if (max_ledger > ledger.ledger_index) {
api.off("ledgerClosed", ledger_listener)
// Transaction may yet be confirmed. This would not be a bad time
// to resubmit the transaction just in case.
} else {
// Work around https://github.com/ripple/rippled/issues/3750
if (await server_has_ledger_range(min_ledger, max_ledger)) {
reject({
failure_final: true,
msg: `Transaction not found in ledgers ${min_ledger}-${max_ledger}. This result is final if this range is correct.`
})
} else {
reject({
failure_final: false,
msg: "Can't get final result. Check a full history server."
})
}
}
}
} else {
// Unknown error; pass it back up
reject({
failure_final: false,
msg: `Unknown Error: ${e}`
})
}
}
} // end ledger event handler
api.on('ledgerClosed', ledger_listener)
}) // end promise def
}
// Submit a transaction blob and get its final result as a string.
// This can be one of these possibilities:
// tesSUCCESS. The transaction executed successfully.
// tec*. The transaction was validated with a failure code. It destroyed the XRP
// transaction cost and may have done some cleanup such as removing
// expired objects from the ledger, but nothing else.
// See https://xrpl.org/tec-codes.html for the full list.
// tefMAX_LEDGER. The transaction expired without ever being included
// in a validated ledger.
// unknown. Either the server you are querying does not have the
// necessary ledger history to find the transaction's final result, or
// something else went wrong when trying to look up the results. The
// warning written to the console can tell you more about what happened.
async function submit_and_verify(api, tx_blob) {
// Make sure we subscribe to the ledger stream. This is idempotent so we don't
// have to worry about oversubscribing.
api.request({"command": "subscribe", "streams": ["ledger"]})
const prelim = await api.request({"command": "submit", "tx_blob": tx_blob})
console.log("Preliminary result code:", prelim.result.engine_result)
const min_ledger = prelim.result.validated_ledger_index
if (prelim.result.tx_json.LastLedgerSequence === undefined) {
console.warn("Transaction has no LastLedgerSequence field. "+
"It may be impossible to determine final failure.")
}
const max_ledger = prelim.result.tx_json.LastLedgerSequence
const tx_id = prelim.result.tx_json.hash
let final_result
try {
final_result = await lookup_tx_final(api, tx_id, max_ledger, min_ledger)
} catch(reason) {
if (reason.failure_final) final_result = "tefMAX_LEDGER"
else final_result = "unknown"
console.warn(reason)
}
return final_result;
}
// Exports for node.js; no-op for browsers
if (typeof module !== "undefined") {
module.exports = {
submit_and_verify: submit_and_verify,
lookup_tx_final: lookup_tx_final
}
}