ssh2-sftp-client reconnect on error demostration

.env.example

SFTP_USER=
SFTP_HOST=127.0.0.1
SFTP_PORT=22
SFTP_PASSWORD=

ssh2-sftp-client-reconnect-on-error-demostration.js

require('dotenv').config()
const max = 1000
const SftpClient = require('ssh2-sftp-client')
const sleep = ms => new Promise(resolve => setTimeout(resolve, ms))

const { SFTP_HOST, SFTP_USER, SFTP_PORT, SFTP_PASSWORD } = process.env

const sftpConfig = {
  host: SFTP_HOST,
  port: SFTP_PORT,
  username: SFTP_USER,
  password: SFTP_PASSWORD,
  // keepaliveInterval: 30,
  retries: 30,
  retry_minTimeout: 5000
}
console.log(sftpConfig)

const reconnect = async oldSftp => {
  if (oldSftp !== undefined) {
    try {
      await oldSftp.end()
    } catch (err) {
      console.log('not able to call end() on the original sftp client: ', err)
    }
  }
  const sftp = new SftpClient()
  await sleep(5000)
  await sftp.connect(sftpConfig)
  return sftp
}

const run = async () => {
  let sftp = await reconnect()
  sftp.on('error', async error => {
    console.log(`sftp error handling: ${error.message}`)
    sftp = await reconnect(sftp)
  })

  const listDir = async () => {
    let listFiles
    try {
      listFiles = await sftp.list('/', '*.txt')
      const files = listFiles.map(f => f.name)
      return files
    } catch (err) {
      console.log(`list: sftp error: ${err.message}`)
      sftp = await reconnect()
      return []
    }
  }
  for (let cnt = 0; cnt < max; cnt++) {
    console.time(`listing-${cnt}`)
    console.log(await listDir())
    console.timeEnd(`listing-${cnt}`)
    await sleep(2000)
  }
}

run()

// to test, 1. create .env based on .env.example 2. run `node index.js`, 
// after some seconds, reboot the target sftp server and watch the listing
// continues after sftp server is back on line again.