Sending Emails with Nodemailer

Why Send Emails from Node.js?

Common use cases:

• Welcome emails after signup
• Password reset links
• Order confirmations
• Notifications
• Reports

Setup

npm install nodemailer

const nodemailer = require('nodemailer');

const transporter = nodemailer.createTransporter({
  host: 'smtp.gmail.com',
  port: 587,
  secure: false,
  auth: {
    user: 'your-email@gmail.com',
    pass: 'your-app-password'
  }
});

Note: Use App Password, not regular Gmail password.

Send Basic Email

async function sendEmail() {
  await transporter.sendMail({
    from: '"Your Name" <your-email@gmail.com>',
    to: 'recipient@example.com',
    subject: 'Hello from Node.js',
    text: 'Plain text content',
    html: '<b>HTML content</b>'
  });
}

Real Example: Welcome Email

async function sendWelcomeEmail(user) {
  const html = `
    <h1>Welcome, ${user.name}!</h1>
    <p>Thank you for signing up.</p>
    <a href="https://example.com/verify?token=${user.verifyToken}">
      Verify Email
    </a>
  `;
  
  await transporter.sendMail({
    from: '"MyApp" <noreply@example.com>',
    to: user.email,
    subject: 'Welcome to MyApp',
    html
  });
}

Real Example: Password Reset

async function sendPasswordReset(user, resetToken) {
  const resetURL = `https://example.com/reset-password?token=${resetToken}`;
  
  const html = `
    <h2>Password Reset Request</h2>
    <p>Click the link below to reset your password:</p>
    <a href="${resetURL}">Reset Password</a>
    <p>This link expires in 1 hour.</p>
  `;
  
  await transporter.sendMail({
    to: user.email,
    subject: 'Password Reset',
    html
  });
}

Queue Emails (Production)

const Queue = require('bull');
const emailQueue = new Queue('email');

async function queueEmail(to, subject, html) {
  await emailQueue.add({ to, subject, html });
}

emailQueue.process(async (job) => {
  const { to, subject, html } = job.data;
  
  await transporter.sendMail({
    from: 'noreply@example.com',
    to,
    subject,
    html
  });
});

await queueEmail('user@example.com', 'Welcome', '<h1>Welcome!</h1>');

Why queue? Don't block HTTP response waiting for email to send.

Key Takeaway

Use Nodemailer for sending emails. Queue emails in production for reliability. Use HTML templates for better design. Always handle errors. Consider services like SendGrid for high volume.