Setting Up the Mail Catcher Service

Oct 13, 2025 by talynt.org 87 views

Introduction

In today's digital age, email services play a crucial role in various applications, including account validation. When creating a new account, users need to verify their email address to ensure that they are genuine individuals. This process involves sending a verification email to the user's registered email address. In this article, we will explore the process of setting up a reliable email service using Docker, Node.js, and the nodemailer module.

Prerequisites

Before we dive into the implementation, let's outline the prerequisites for this project:

An email needs to be sent to the user to validate the account.
We will use Docker to create a new container for the mail catcher service.
We will utilize the nodemailer module to send emails.
We will tweak the orchestrator to consult the last mail sent and clear the inbox.

Setting Up the Mail Catcher Service

To set up the mail catcher service, we will create a new Docker container using the mailcatcher image. This will allow us to catch and store emails sent to the user's account.

Step 1: Create a New Docker Container

First, we need to create a new Docker container for the mail catcher service. We can do this by running the following command:

docker run -d --name mailcatcher -p 1080:1080 mailcatcher/mailcatcher

This command creates a new Docker container named mailcatcher and maps port 1080 from the container to port 1080 on the host machine.

Step 2: Create a Mail Catcher Service

Next, we need to create a mail catcher service that will catch and store emails sent to the user's account. We can do this by creating a new Node.js service that uses the nodemailer module to send emails.

const nodemailer = require('nodemailer');

const transporter = nodemailer.createTransport({
  host: 'localhost',
  port: 1080,
  secure: false,
});

const mailOptions = {
  from: 'your-email@example.com',
  to: 'user-email@example.com',
  subject: 'Account Verification',
  text: 'Please click on the following link to verify your account: http://example.com/verify',
};

transporter.sendMail(mailOptions, (error, info) => {
  if (error) {
    console.log(error);
  } else {
    console.log('Email sent: ' + info.response);
  }
});

This code creates a new nodemailer transporter that connects to the mail catcher service on port 1080. It then sends an email to the user's account with a verification link.

Step 3: Tweak the Orchestrator

To complete the email service, we need to tweak the orchestrator to consult the last mail sent and clear the inbox. We can do this by modifying the orchestrator to check the mail catcher service for new emails and clear the inbox when the user verifies their account.

const mailcatcher = require('mailcatcher');

const mailcatcherClient = new mailcatcher.Client({
  host: 'localhost',
  port: 1080,
});

mailcatcherClient.getMessages((error, messages) => {
  if (error) {
    console.log(error);
  } else {
    const lastMessage = messages[messages.length - 1];
    if (lastMessage.subject === 'Account Verification') {
      // Clear the inbox
      mailcatcherClient.clearInbox();
    }
  }
});

This code creates a new mailcatcher client that connects to the mail catcher service on port 1080. It then checks the last message in the inbox and clears the inbox if the subject is 'Account Verification'.

Testing the Email Service

To test the email service, we need to send a verification email to the user's account and verify that the email is sent correctly. We can do this by running the following command:

node send-email.js

This command sends a verification email to the user's account using the nodemailer module.

Conclusion

In this article, we explored the process of setting up a reliable email service using Docker, Node.js, and the nodemailer module. We created a new Docker container for the mail catcher service, created a mail catcher service that uses the nodemailer module to send emails, and tweaked the orchestrator to consult the last mail sent and clear the inbox. We also tested the email service by sending a verification email to the user's account and verifying that the email is sent correctly.

Future Improvements

There are several future improvements that we can make to the email service. Some of these improvements include:

Implementing email validation to ensure that the user's email address is valid.
Implementing email encryption to ensure that the email is secure.
Implementing email tracking to track the email's delivery status.
Implementing email templates to customize the email's content.

By implementing these improvements, we can make the email service more reliable and secure, and provide a better experience for the user.

References

Mail Catcher
Nodemailer
Docker
Email Service Q&A =====================

Frequently Asked Questions

In this article, we will answer some of the most frequently asked questions about the email service.

Q: What is the purpose of the email service?

A: The purpose of the email service is to send verification emails to users who create a new account. This ensures that the user is a genuine individual and helps to prevent spam accounts.

Q: How does the email service work?

A: The email service works by sending an email to the user's account with a verification link. The user clicks on the link to verify their account, and the email service checks the mail catcher service for new emails and clears the inbox when the user verifies their account.

Q: What is the mail catcher service?

A: The mail catcher service is a Docker container that catches and stores emails sent to the user's account. It is used to verify the user's email address and to clear the inbox when the user verifies their account.

Q: How do I set up the mail catcher service?

A: To set up the mail catcher service, you need to create a new Docker container using the mailcatcher image. You can do this by running the following command:

docker run -d --name mailcatcher -p 1080:1080 mailcatcher/mailcatcher

Q: How do I send emails using the email service?

A: To send emails using the email service, you need to use the nodemailer module to send emails to the user's account. You can do this by creating a new Node.js service that uses the nodemailer module to send emails.

Q: How do I test the email service?

A: To test the email service, you need to send a verification email to the user's account and verify that the email is sent correctly. You can do this by running the following command:

node send-email.js

Q: What are some future improvements for the email service?

A: Some future improvements for the email service include:

Implementing email validation to ensure that the user's email address is valid.
Implementing email encryption to ensure that the email is secure.
Implementing email tracking to track the email's delivery status.
Implementing email templates to customize the email's content.

Q: How do I troubleshoot issues with the email service?

A: To troubleshoot issues with the email service, you can check the mail catcher service for new emails and clear the inbox when the user verifies their account. You can also check the email service logs for any errors or issues.

Conclusion

In this article, we answered some of the most frequently asked questions about the email service. We covered topics such as the purpose of the email service, how it works, and how to set it up. We also discussed some future improvements for the email service and how to troubleshoot issues with it.