I'm looking for a simple way to programmatically send emails from a Linode Ubuntu server (not bulk or spamming, simple iOT type notifications). I have a dockerized postfix/dovecot system up and running, but I don't know how to use that from outside the container. I've looked into sendmail but that seems like duplication since I already have a configured SMTP server. My question is what can I install on my Ubuntu server that will allow me to send simple emails from the command line (script) that uses my existing SMTP server in my docker container?
For this problem, the easiest solution I have found is nodemailer, as my application that needs to send the emails is a node.js application, and I connect to it as you would from an email client.