Sending emails with Mailgun is straightforward.

Overview

Mailgun

Google Domains

MXToolBox

GoogleAdminToolBox

Google Admin Console

Configuring DMARC for Google Workspace

Introduction

Previously I used Nodemailer and Gmail to send emails. For details, see Sending Emails from Express Application and Google Gmail Configuration. For a variety of reasons, I chose to move away from Gmail.

Mailgun

Mailgun

• Sign up for an account

A sandbox domain will be provided which is useful for basic development and verification of the environment.

However, for proper application usage, it is necessary to

• Upgrade

Now it is possible to create a custom domain.

• Dashboard
• Domains
  • Add New Domain

I chose to use a domain I already own, thus

• Domain Name: mg.my-domain.com
• US
• 1024

When the domain is added, some DNS changes are required to the my-domain.com domain.

Add DNS entries

From Mailgun Dashboard

• Select domain mg.my-domain.com
• Select Domain Settings
• Select DNS records

Notice the SPF, DKIM, MX and CNAME records. These need to be added as DNS entries to the domain.

Add the following DNS records

Type: CNAME
Hostname: email.mg
Value: mailgun.org

Type: TXT
Hostname: mg
Value: v=spf1 include:mailgun.org ~all

Type: TXT
Hostname: pic._domainkey.mg
Value: paste value here

Type: MX
Hostname: mg
Value: mxa.mailgun.org

Type: MX
Hostname: mg
Value: mxb.mailgun.org

Using Google Domains, the changes are propagated almost immediately.

See section 4, Wait for your domain to verify

• Verify DNS Settings.

Once the DNS settings have been verified, Mailgun is ready for use.

Verify SPF and DKIM

To verify these are working:

• MXToolBox
• Choose SPF Record Lookup
• Enter mg.johnvincent.io

should show

v=spf1 include:mailgun.org ~all

• Choose DKIM Lookup
• Enter pic._domainkey.mg.johnvincent.io

should show

v=DKIM1; k=rsa; p= ........ 

Search for DMARC record

• MXToolBox
• Choose DMARC Lookup
• Enter mg.johnvincent.io

should show

No DMARC Record found

Add DMARC record

To add a basic DMARC DNS record

• Start Google Domains
• Select the domain
• DNS

Create new record

• Host name: _dmarc.mg
• Type: TXT
• TTL: 1 hour
• Data: v=DMARC1; p=none; pct=100; sp=none; rua=mailto:postmaster@johnvincent.io; adkim=r; aspf=r

Retest with MXToolBox

Reports

Reports will be sent to postmaster@johnvincent.io. Ensure the email id has been created.

Lookup your Mailgun API Keys

• Dashboard
• API Keys (on the right)
• Copy the Private API key and paste into the code below.

Code

The following is fairly self explanatory.

Configuration code in config.js

const CONFIG = {
	MAILGUN: {
		apiKey: 'your-mailgun-api-key',
		domain: 'your-mailgun-domain'
	}
};

exports.CONFIG = CONFIG;

Sending emails with Mailgun in email.js

const Mailgun = require('mailgun-js');

const { CONFIG } = require('./config');
const { APPLICATION_NAME, MAIL_FROM_EMAIL, MAIL_SUPPORT_EMAIL, MAIL_TEST_EMAILS } = CONFIG;

....

	handleTestEmails() {
		const subject = `${APPLICATION_NAME}; Email Testing`;
		const text = `Testing the email system`;
		const html = `<h1>Email Test</h1><p>Testing message for ${APPLICATION_NAME}</p>`;
		const emailData = {
			from: `${MAIL_FROM_EMAIL}`,
			subject,
			text,
			html
		};
		MAIL_TEST_EMAILS.forEach(emailId => {
			console.log('emailId ', emailId);
			emailData.to = `${emailId}`;
			this.sendEmail(emailData);
		});
	}

	sendEmail(emailData) {
		logger.info('--- config/email::sendEmailWithMailgun, emailData ', emailData);

		const { MAILGUN } = CONFIG;

		const mailgun = new Mailgun({apiKey: MAILGUN.apiKey, domain: MAILGUN.domain});

		logger.info(`Attempting to send email from ${emailData.from}`);
		mailgun.messages().send(emailData, (err, body) => {
			if (err) {
				logger.error(`Problem sending email: ${err}`);
				console.log("got an error: ", err);
			}
			else {
				logger.info(`Email sent; body `, body);
			}
		});
	}