Sending an SMTP email in Dart

dart, email

Solution

There's a library called `mailer`, which does exactly what you asked for: sends out emails.

Set it as a dependency in your `pubspec.yaml` and run `pub install`:

dependencies:
  mailer: any

I will give a simple example using Gmail on my local Windows machine:

import 'package:mailer/mailer.dart';

main() {
  var options = new GmailSmtpOptions()
    ..username = 'kaisellgren@gmail.com'
    ..password = 'my gmail password'; // If you use Google app-specific passwords, use one of those.

  // As pointed by Justin in the comments, be careful what you store in the source code.
  // Be extra careful what you check into a public repository.
  // I'm merely giving the simplest example here.

  // Right now only SMTP transport method is supported.
  var transport = new SmtpTransport(options);

  // Create the envelope to send.
  var envelope = new Envelope()
    ..from = 'support@yourcompany.com'
    ..fromName = 'Your company'
    ..recipients = ['someone@somewhere.com', 'another@example.com']
    ..subject = 'Your subject'
    ..text = 'Here goes your body message';

  // Finally, send it!
  transport.send(envelope)
    .then((_) => print('email sent!'))
    .catchError((e) => print('Error: $e'));
}

The `GmailSmtpOptions` is just a helper class. If you want to use a local SMTP server:

var options = new SmtpOptions()
  ..hostName = 'localhost'
  ..port = 25;

You can check here for all possible fields in the `SmtpOptions` class.

Here's an example using the popular Rackspace Mailgun:

var options = new SmtpOptions()
  ..hostName = 'smtp.mailgun.org'
  ..port = 465
  ..username = 'postmaster@yourdomain.com'
  ..password = 'from mailgun';

The library supports HTML emails and attachments as well. Check out the example to learn how to do that.

I am personally using `mailer` with Mailgun in production use.

Problem

I looked through the API documentation and language guide, but I did not see anything about sending emails in Dart. I also checked this google groups post, but it's quite old by Dart standards. Is this possible to do? I know that I can always use the Process class to invoke external programs, but I'd prefer a real Dart solution if there's any.

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