Forewords

I needed a way to test mail confirmation. When you are dealing with deb authentication you would like to be sure that this email exist. And usually I use is_email_confirmed column next to user credentials in the database table. Once user hits siging endpoint as last step I send an email with confirmation token.

I was looking on few popular tools across the Internet:

• https://mailtrap.io/
• https://mailcow.email/
• https://mailu.io/1.7/
• https://poste.io/

What I found

My requirements were: run in docker, easy to config, basic functionality to render email. All things above quite heavy apps with complex configuration. After that I found found nice and lightweight way how to test it locally.

-> https://github.com/mailhog/MailHog

Setup

# docker-compose.dev.yml
...
  mailhog:
    image: mailhog/mailhog
    container_name: mailhog
    restart: always
    ports:
      - '8025:8025'
      - '1025:1025'
...

I did the small package in my project and now I can use it around my services to send emails and catch them in mailhog!

About golang smtp you can checkout here

• https://github.com/golang/go/wiki/SendingMail
• https://golang.org/pkg/net/smtp/

package main

import (
	"bytes"
	"log"
	"net/smtp"
)

func main() {
    // Connect to the remote SMTP server.
	c, err := smtp.Dial("localhost:1025")
	if err != nil {
		log.Fatal(err)
	}
	defer c.Close()
	// Set the sender and recipient.
	c.Mail("sender@example.org")
	c.Rcpt("recipient@example.net")
	// Send the email body.
	wc, err := c.Data()
	if err != nil {
		log.Fatal(err)
	}
	defer wc.Close()
	buf := bytes.NewBufferString("This is the email body.")
	if _, err = buf.WriteTo(wc); err != nil {
		log.Fatal(err)
	}
}

I would recommend setting this up via env, check my post about it.

Not sure if it will be useful to anyone, but i decided to share it.

Cover from github.com/ashleymcnamara/gophers.