Ruby on Rails: How to setup and use MailCatcher to capture and test emails locally

Testing email features in Ruby on Rails can be tricky without the right tools. MailCatcher makes it easy by acting as a local email server where you can view and debug your emails in a web interface.

This guide will show you how to set up and use MailCatcher in your Rails app, making email testing simple and effective.

Setup

1. Install the mailcatcher gem by running this command in your console. It will install the gem locally:

   gem install mailcatcher
   

2. Configure the ActionMailer settings of your Rails project by adding these lines of code to config/environments/development.rb:

   config.action_mailer.raise_delivery_errors = false
   config.action_mailer.delivery_method = :smtp
   config.action_mailer.smtp_settings = {
     address: '127.0.0.1',
     port: 1025,
   }
   

1. Start mailcatcher by running the command mailcatcher in the terminal.

2. Go to http://127.0.0.1:1080/, where you can access the web interface.

MailCatcher

After completing the setup, you will be able to send emails from your Rails application and view them instantly in the MailCatcher web interface.

This interface lists all captured emails, allowing you to view the email subject, sender, recipient, and time of receipt at a glance.

Clicking on an email reveals its full content. You can inspect the email headers to verify details like the sender’s address, recipient(s), and subject. You can also view the HTML, Plain Text, and Source versions of the email body.

Summary

In essence, MailCatcher serves as a valuable tool for ensuring your email functionality is robust and error-free during the development and testing phases of your Rails project.

It provides a safe environment to experiment with email templates, test different scenarios, and validate email delivery settings without affecting real users.

This capability not only enhances development efficiency but also helps in debugging and fine-tuning your email features before they go live.