/config/mail.js

Purpose

This module is responsible for managing email registration workflows, including:

1. Creating a new user with a temporary password.

2. Saving the user's email to a mailing list.

3. Sending a registration email with the temporary password via Mailgun.

Prerequisites

This module relies on the following environment variables to function correctly:

• MAILGUN_API_KEY: Your Mailgun API key for authenticating email delivery.

• MAILGUN_DOMAIN: The domain associated with your Mailgun account.

Dependencies

The module makes use of several packages and custom helper files:

• nodemailer and nodemailer-mailgun-transport: For configuring and sending emails through Mailgun.

• bcrypt: Used to hash the temporary password for secure storage.

• mongoose: Handles database operations, specifically to save the user and email details.

• Custom Helpers and Models:

  • generateTemporaryPassword from passwordHelper: Generates a random temporary password for user registration.

  • UserModel and EmailList models: Manage user and email list data in MongoDB.

Environment Setup

To configure the Mailgun transporter, you need to define the following in your .env file:

MAILGUN_API_KEY=<Your Mailgun API Key>
MAILGUN_DOMAIN=<Your Mailgun Domain>

Functions

transporter

A Mailgun transporter instance is created with nodemailer using the API key and domain, allowing for secure, authenticated email transmission.

const transporter = nodemailer.createTransport(
  mailgunTransport({
    auth: {
      api_key: process.env.MAILGUN_API_KEY,
      domain: process.env.MAILGUN_DOMAIN,
    },
  })
);

sendRegistrationEmail(email)

This asynchronous function performs the following steps:

1. Generate and Hash Password: Uses generateTemporaryPassword to create a temporary password and hashes it with bcrypt before saving it in the database.

2. Create User Record: Creates a new user in MongoDB with the temporary password and an email identifier.

3. Email List Management: Adds the email to a mailing list (using MongoDB’s upsert functionality to prevent duplicates).

4. Compose and Send Email: Sends a registration email containing the temporary password, instructing the user to update their password upon first login.

Parameters

• email (string): The recipient’s email address.

Sample Email Content

• Subject: “Welcome to Our Service!”

• Body:

  • HTML and plain text versions are included, with instructions for logging in and changing the password.

Notes

• Customization: Update the from field in mailOptions with your service's email address.

• Asynchronous Email Handling: sendMail runs asynchronously, with results logged to the console.

This file is intended to provide a general-purpose email registration solution, with flexibility for future enhancements or modifications.

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This documentation outlines the setup, functionality, and use of /config/mail.js.