xrpl-dev-portal/_code-samples/verify-credential/js/verify_credential.js

import { Client, rippleTimeToISOTime, convertStringToHex } from 'xrpl'

const client = new Client('wss://s.devnet.rippletest.net:51233')
await client.connect()

const SUBJECT_ADDRESS = 'rsYhHbanGpnYe3M6bsaMeJT5jnLTfDEzoA'
const ISSUER_ADDRESS = 'rEzikzbnH6FQJ2cCr4Bqmf6c3jyWLzkonS'
const CREDENTIAL_TYPE = convertStringToHex('my_credential').toUpperCase()

// Look up Credential ledger entry --------------------------------------------
const ledgerEntryRequest = {
  command: 'ledger_entry',
  credential: {
    subject: SUBJECT_ADDRESS,
    issuer: ISSUER_ADDRESS,
    credential_type: CREDENTIAL_TYPE,
  },
  ledger_index: 'validated',
}
console.log('Looking up credential...')
console.log(JSON.stringify(ledgerEntryRequest, null, 2))

let xrplResponse
try {
  xrplResponse = await client.request(ledgerEntryRequest)
} catch (err) {
  if (err.data?.error === 'entryNotFound') {
    console.error('Credential was not found')
  } else {
    console.error(err)
  }
  process.exit(1)
}

const credential = xrplResponse.result.node
console.log('Found credential:')
console.log(JSON.stringify(credential, null, 2))

// Check if the credential has been accepted ----------------------------------
const lsfAccepted = 0x00010000
if (!(credential.Flags & lsfAccepted)) {
  console.log('Credential is not accepted.')
  process.exit(2)
}

// Confirm that the credential is not expired ---------------------------------
if (credential.Expiration) {
  const expirationTime = rippleTimeToISOTime(credential.Expiration)
  console.log(`Credential has expiration: ${expirationTime}`)
  console.log('Looking up validated ledger to check for expiration.')

  const ledgerResponse = await client.request({
    command: 'ledger',
    ledger_index: 'validated',
  })

  const closeTime = rippleTimeToISOTime(ledgerResponse.result.ledger.close_time)
  console.log(`Most recent validated ledger was at: ${closeTime}`)

  if (new Date(closeTime) > new Date(expirationTime)) {
    console.log('Credential is expired.')
    process.exit(3)
  }
}

// Credential has passed all checks -------------------------------------------
console.log('Credential is valid.')
client.disconnect()