In this guide, we will walk you through the process of sending password or email verification links using Node.js. We will cover the necessary steps, tools, and configurations to set up a basic application that can send verification emails via Express and Nodemailer.

The first step is to create a new project directory and initialize it with npm.

Create a new directory for your project: Initialize the directory with npm: mkdir email-verification
cd email-verification
npm init -y

You will need Express for the web server and Nodemailer for sending emails. Install these packages via npm.

npm install express nodemailer dotenv

Create a .env file in the root of your project to store your email credentials securely.

.env

EMAIL_USERyour-email@
EMAIL_PASSyour-email-password

Create an index.js file and set up a basic Express server.

// index.js
const express require('express');
const nodemailer require('nodemailer');
require('dotenv').config();

const app express();
const PORT 3000;

express.json();

// Endpoint to send verification email
/send-verification async (req, res) {
const { email } ;
const verificationLink `http://localhost:${PORT}/verify?token${()};

const transporter {
service: 'gmail', // You can use other services like SendGrid, Mailgun, etc.
auth: {
user: _USER,
pass: _PASS
}
};

const mailOptions {
from: _USER,
to: email,
subject: 'Email Verification',
text: `Please verify your email by clicking the link: ${verificationLink}`
};

try {
await (mailOptions);
(200).send();
} catch (error) {
( (500).send();
}
}

(PORT, () > {
console.log(` });
}

Start your server with the following command:

node index.js

You can test the email verification endpoint using a tool like Postman or cURL. Send a POST request to http://localhost:3000/send-verification with a JSON body containing the email address.

{
"email": ""
}

For a real application, you will want to generate a unique token for each user. You can use libraries like jsonwebtoken to create a secure token.

Note: In the above example, we used a simple random string generator for demonstration purposes. In a production environment, you should use a secure token generation method.

Implement a route to handle the verification link when the user clicks it. You will need to validate the token and perform the necessary actions.

Ensure you handle errors and validate email addresses properly. Consider using HTTPS for secure communication.

Note: It is important to handle errors gracefully to prevent sensitive information from being exposed.

Depending on your email service provider, you might need to adjust the transporter configuration. For example, you might need to use OAuth2 for Gmail.

This setup provides a basic framework for sending email verification links in a Node.js application. You can expand upon it based on your specific requirements. Whether you are building a user authentication system, or need to securely send important notifications, this guide should give you a strong foundation to get started.