How to send direct email with DKIM enabled with nodemailer?

Question

How can I send direct email via nodemailer with DKIM enabled?

I tried

const nodemailer = require('nodemailer')
const directTransport = require('nodemailer-direct-transport')

const transporter = nodemailer.createTransport(
  directTransport({
    dkim: {
      domainName: "mydomain.com",
      keySelector: "mail",
      privateKey: "<generated private key>"
    }
  }))

require('express')().get('/test', (req, res, next) => {
  console.log('sending mail')
  mailer.sendMail({
    from: 'support@mydomain.com',
    to: 'pmmEoRzqH5EyTO@dkimvalidator.com',
    subject: 'test email',
    html: 'Email content'
  }, (err, reply) => {
    console.log('email sent')
    console.log(err && err.stack)
    console.dir(reply)
  })
  res.send('test').end()
})

I also added the public key as TXT record to my DNS panel.

The email was sent but without DKIM as I checked at http://dkimvalidator.com/results

DKIM Information: DKIM Signature

This message does not contain a DKIM Signature

Is there anyone had succeed with this? This looks a straight forward cheap way to send email without setting up SMTP server but I did not see any post on this.

Answer 1

Finally, I figured out my own solution.

nodemailer is big project but it looks lack of maintainer. Non-bug-report issue is closed by default.

I switched to sendmail then everything works like a charm