Sending Transactional Email via SMTP

This article provides working code examples for sending transactional email through MigoSMTP using SMTP in six programming languages and frameworks. Each example follows security best practices — credentials are read from environment variables, not hard-coded.

Connection Details Recap

PHP — PHPMailer (Most Common)

<?php
use PHPMailerPHPMailerPHPMailer;
use PHPMailerPHPMailerSMTP;
use PHPMailerPHPMailerException;

require 'vendor/autoload.php';

$mail = new PHPMailer(true);

try {
    // SMTP configuration
    $mail->isSMTP();
    $mail->Host       = 'smtp.migosmtp.com';
    $mail->SMTPAuth   = true;
    $mail->Username   = getenv('SMTP_USERNAME');
    $mail->Password   = getenv('SMTP_PASSWORD');
    $mail->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
    $mail->Port       = 587;

    // Sender and recipient
    $mail->setFrom('noreply@yourcompany.com', 'Your Company');
    $mail->addAddress('customer@example.com', 'Customer Name');
    $mail->addReplyTo('support@yourcompany.com', 'Support');

    // Content
    $mail->isHTML(true);
    $mail->Subject = 'Your order #12345 has been confirmed';
    $mail->Body    = '<p>Hi Customer, your order has been received.</p>';
    $mail->AltBody = 'Hi Customer, your order has been received.';

    $mail->send();
    echo 'Message sent successfully';
} catch (Exception $e) {
    echo 'Message could not be sent. Error: ' . $mail->ErrorInfo;
}

Python — smtplib (Standard Library)

import os
import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

smtp_host = 'smtp.migosmtp.com'
smtp_port = 587
username  = os.environ['SMTP_USERNAME']
password  = os.environ['SMTP_PASSWORD']

msg = MIMEMultipart('alternative')
msg['Subject'] = 'Your order #12345 has been confirmed'
msg['From']    = 'noreply@yourcompany.com'
msg['To']      = 'customer@example.com'

html_part = MIMEText('<p>Hi Customer, your order has been received.</p>', 'html')
text_part = MIMEText('Hi Customer, your order has been received.', 'plain')
msg.attach(text_part)
msg.attach(html_part)

try:
    with smtplib.SMTP(smtp_host, smtp_port) as server:
        server.ehlo()
        server.starttls()
        server.login(username, password)
        server.sendmail(msg['From'], [msg['To']], msg.as_string())
    print('Email sent successfully')
except Exception as e:
    print(f'Failed to send: {e}')

Node.js — Nodemailer

const nodemailer = require('nodemailer');

const transporter = nodemailer.createTransport({
  host:    'smtp.migosmtp.com',
  port:    587,
  secure:  false,        // false = STARTTLS; true = SSL on port 465
  requireTLS: true,
  auth: {
    user: process.env.SMTP_USERNAME,
    pass: process.env.SMTP_PASSWORD,
  },
});

async function sendEmail() {
  try {
    const info = await transporter.sendMail({
      from:    '"Your Company" <noreply@yourcompany.com>',
      to:      'customer@example.com',
      subject: 'Your order #12345 has been confirmed',
      text:    'Hi Customer, your order has been received.',
      html:    '<p>Hi Customer, your order has been received.</p>',
    });
    console.log('Message sent:', info.messageId);
  } catch (error) {
    console.error('Error:', error);
  }
}

sendEmail();

Ruby — Net::SMTP

require 'net/smtp'

smtp_username = ENV['SMTP_USERNAME']
smtp_password = ENV['SMTP_PASSWORD']
from_address  = 'noreply@yourcompany.com'
to_address    = 'customer@example.com'

message = <<~MESSAGE
  From: Your Company <#{from_address}>
  To: #{to_address}
  Subject: Your order #12345 has been confirmed
  MIME-Version: 1.0
  Content-Type: text/html

  <p>Hi Customer, your order has been received.</p>
MESSAGE

Net::SMTP.start('smtp.migosmtp.com', 587, 'yourcompany.com',
                smtp_username, smtp_password, :login) do |smtp|
  smtp.enable_starttls
  smtp.send_message(message, from_address, to_address)
  puts 'Email sent successfully'
end

Java — Jakarta Mail

import jakarta.mail.*;
import jakarta.mail.internet.*;
import java.util.Properties;

public class SendEmail {
  public static void main(String[] args) throws MessagingException {
    String smtpUser = System.getenv("SMTP_USERNAME");
    String smtpPass = System.getenv("SMTP_PASSWORD");

    Properties props = new Properties();
    props.put("mail.smtp.host", "smtp.migosmtp.com");
    props.put("mail.smtp.port", "587");
    props.put("mail.smtp.auth", "true");
    props.put("mail.smtp.starttls.enable", "true");
    props.put("mail.smtp.ssl.protocols", "TLSv1.2 TLSv1.3");

    Session session = Session.getInstance(props,
      new Authenticator() {
        protected PasswordAuthentication getPasswordAuthentication() {
          return new PasswordAuthentication(smtpUser, smtpPass);
        }
      });

    Message message = new MimeMessage(session);
    message.setFrom(new InternetAddress("noreply@yourcompany.com", "Your Company"));
    message.setRecipients(Message.RecipientType.TO,
      InternetAddress.parse("customer@example.com"));
    message.setSubject("Your order #12345 has been confirmed");

    MimeMultipart content = new MimeMultipart("alternative");
    content.addBodyPart(createPart("Hi Customer, your order is confirmed.", "plain"));
    content.addBodyPart(createPart("<p>Hi Customer, your order is confirmed.</p>", "html"));
    message.setContent(content);

    Transport.send(message);
    System.out.println("Email sent successfully");
  }

  private static MimeBodyPart createPart(String text, String subtype)
      throws MessagingException {
    MimeBodyPart part = new MimeBodyPart();
    part.setText(text, "utf-8", subtype);
    return part;
  }
}

Go — net/smtp

package main

import (
    "crypto/tls"
    "fmt"
    "net/smtp"
    "os"
)

func main() {
    host     := "smtp.migosmtp.com"
    port     := "587"
    username := os.Getenv("SMTP_USERNAME")
    password := os.Getenv("SMTP_PASSWORD")

    auth := smtp.PlainAuth("", username, password, host)

    tlsConfig := &tls.Config{
        InsecureSkipVerify: false,
        ServerName:         host,
        MinVersion:         tls.VersionTLS12,
    }

    conn, err := smtp.Dial(host + ":" + port)
    if err != nil { panic(err) }
    defer conn.Close()

    if err = conn.StartTLS(tlsConfig); err != nil { panic(err) }
    if err = conn.Auth(auth); err != nil { panic(err) }
    if err = conn.Mail("noreply@yourcompany.com"); err != nil { panic(err) }
    if err = conn.Rcpt("customer@example.com"); err != nil { panic(err) }

    wc, err := conn.Data()
    if err != nil { panic(err) }
    fmt.Fprintf(wc, "Subject: Your order confirmed
Content-Type: text/plain

Hi Customer, your order is confirmed.")
    wc.Close()
    conn.Quit()
    fmt.Println("Email sent successfully")
}

Next Steps

• SMTP authentication methods
• Transactional email best practices
• Troubleshooting — SMTP Connection Issues