stacker.news/worker/nostr.js

import { getInvoice } from 'ln-service'
import { Relay, signId, calculateId, getPublicKey } from 'nostr'

const nostrOptions = { startAfter: 5, retryLimit: 21, retryBackoff: true }

export function nip57 ({ boss, lnd, models }) {
  return async function ({ data: { hash } }) {
    console.log('running nip57')

    let inv, lnInv
    try {
      lnInv = await getInvoice({ id: hash, lnd })
      inv = await models.invoice.findUnique({
        where: {
          hash
        }
      })
    } catch (err) {
      console.log(err)
      // on lnd related errors, we manually retry which so we don't exponentially backoff
      await boss.send('nip57', { hash }, nostrOptions)
      return
    }

    // check if invoice still exists since HODL invoices get deleted after usage
    if (!inv) return

    try {
      // if parsing fails it's not a zap
      console.log('zapping', inv.desc)
      const desc = JSON.parse(inv.desc)
      const ptag = desc.tags.filter(t => t?.length >= 2 && t[0] === 'p')[0]
      const etag = desc.tags.filter(t => t?.length >= 2 && t[0] === 'e')[0]
      const atag = desc.tags.filter(t => t?.length >= 2 && t[0] === 'a')[0]
      const relays = desc.tags.find(t => t?.length >= 2 && t[0] === 'relays').slice(1)

      const tags = [ptag]
      if (etag) tags.push(etag)
      if (atag) tags.push(atag)
      tags.push(['bolt11', lnInv.request])
      tags.push(['description', inv.desc])
      tags.push(['preimage', lnInv.secret])

      const e = {
        kind: 9735,
        pubkey: getPublicKey(process.env.NOSTR_PRIVATE_KEY),
        created_at: Math.floor(new Date(lnInv.confirmed_at).getTime() / 1000),
        content: '',
        tags
      }
      e.id = await calculateId(e)
      e.sig = await signId(process.env.NOSTR_PRIVATE_KEY, e.id)

      console.log('zap note', e, relays)
      await Promise.allSettled(
        relays.map(r => new Promise((resolve, reject) => {
          const timeout = 1000
          const relay = Relay(r)

          function timedout () {
            relay.close()
            console.log('failed to send to', r)
            reject(new Error('relay timeout'))
          }

          let timer = setTimeout(timedout, timeout)

          relay.on('open', () => {
            clearTimeout(timer)
            timer = setTimeout(timedout, timeout)
            relay.send(['EVENT', e])
          })

          relay.on('ok', () => {
            clearTimeout(timer)
            relay.close()
            console.log('sent zap to', r)
            resolve()
          })
        })))
    } catch (e) {
      console.log(e)
    }
    console.log('done running nip57')
  }
}