Email previews in Ruby on Rails - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of email previews in Rails?

Email previews let you see how your emails will look in a browser before sending them. This helps catch mistakes and design issues early.

beginner

Where do you place email preview files in a Rails app?

Email preview files go in the test/mailers/previews folder by default. Rails uses these to show previews in the browser.

beginner

How do you access email previews in a Rails development environment?

You open http://localhost:3000/rails/mailers in your browser to see a list of email previews.

intermediate

How do you define a preview method inside a preview class?

Inside the preview class, define a method that returns the mailer method call with sample data. For example: def welcome_email; UserMailer.welcome_email(User.first); end

beginner

Why is it helpful to use email previews during development?

Email previews save time by letting you check email content and layout without sending real emails. This avoids spamming users and speeds up design fixes.

Where do Rails email previews live by default?

A config/mailers

B app/mailers/previews

C app/views/mailers

D test/mailers/previews

Rails expects email preview files in the test/mailers/previews folder.

How do you view email previews in Rails development?

A Check logs/mail_preview.log

B Visit /rails/mailers in the browser

C Run rails email:preview command

D Use rails console to call preview methods

You open http://localhost:3000/rails/mailers to see previews.

What does an email preview method return?

A A mailer method call that returns a Mail::Message

B A string with email content

C A JSON object with email data

D A plain text file

The preview method calls a mailer method which returns a Mail::Message object.

Why should you use email previews instead of sending test emails?

A Previews are faster and avoid spamming real inboxes

B Previews automatically send emails to all users

C Previews encrypt emails for security

D Previews only work in production

Previews let you check emails quickly without sending real emails.

Which Rails class do you create to define email previews?

A MailerPreview

B EmailPreviewer

C ActionMailer::Preview

D PreviewMailer

Email preview classes inherit from ActionMailer::Preview.

Explain how to set up and use email previews in a Rails app.

Think about where files go, what classes to use, and how to see previews.

Describe the benefits of using email previews during Rails development.

Consider how previews save time and prevent mistakes.