Create Escrow in incrementing instalments

index.mjs

import fetch from 'node-fetch'
import { XrplDefinitions, derive, sign } from 'xrpl-accountlib'

const now = new Date()

const Server = 'https://xahau-test.net' // can be testnet, xahau-test.net / xahau.network
const secret = '{sender secret}' // can be RK secret
const Account = derive.familySeed(secret)
Account.address = '{sender account r-address}'

const Destination = '{destination r-address}'
const XahAmount = 10_000 // in XAH
const Instalments = 24 // months
const StartAtInstalment = 0 // skip if already at some place

const ServerDefinitions = (await (await fetch(Server + '/server_definitions')).json()).result
const ServerInfo = (await (await fetch(Server + '/server_info')).json()).result
const AccountInfo = (await (await fetch(Server + '/account_info?account=' + Account.address)).json()).result

let iteration = 0
let AccountTxnID
let Sequence = AccountInfo.account_data.Sequence

const definitions = new XrplDefinitions(ServerDefinitions)

const submit = async signed => {
  // For next tx
  Sequence++
  AccountTxnID = signed.id

  const submitted = await (await fetch(Server, {
    method: 'POST',
    headers: { 'content-type': 'application/json' },
    body: JSON.stringify({
      method: 'submit',
      params: [ { tx_blob: signed.signedTransaction, } ]
    })
  })).json()

  console.log(submitted)

  return submitted
}

const releaseDates = Array(Instalments)
  .fill()
  .map((_, index) => new Date(now.getFullYear(), now.getMonth() + ++index, 1))
  .map(r => Math.round(Number(r) / 1000) - 946684800)

if (typeof AccountInfo.account_data.AccountTxnID === 'undefined') {
  // First set tracking of Account TX ID
  const tx = {
    TransactionType: 'AccountSet',
    Fee: String(40),
    SetFlag: 5, // asfAccountTxnID
    Account: Account.address,
    NetworkID: ServerInfo.info.network_id,
    Sequence,
  }

  const signed = sign(tx, Account, definitions)
  console.log(signed)
  await submit(signed)
  // First one not required
  AccountTxnID = undefined
}
///

for await (const FinishAfter of releaseDates) {
  iteration++

  if (iteration > StartAtInstalment) {
    const tx = {
      TransactionType: 'EscrowCreate',
      Account: Account.address,
      Destination,
      Fee: String(1337),
      Amount: String(XahAmount * iteration * 1_000_000),
      NetworkID: ServerInfo.info.network_id,
      FinishAfter,
      AccountTxnID,
      Sequence,
    }

    console.log(tx.Amount)

    // This makes it real
    const signed = sign(tx, Account, definitions)
    console.log(signed)
    await submit(signed)
    await new Promise(resolve => setTimeout(resolve, 4500))
  }
}