Letter opener in a rails engine

We can use letter_opener https://github.com/ryanb/letter_opener to open up the email we sent in browser while we are developing. But when we are testing for sending out dozens of emails, opening up so much tab is not a good thing.

Letter_opener_web https://github.com/fgrehm/letter_opener_web provides a web app for you to view all the emails sent in one place.

# in Gemfile
gem 'letter_opener_web'

# in environments/development.rb
config.action_mailer.delivery_method = :letter_opener_web

# in routes.rb
if Rails.env.development?
  mount LetterOpenerWeb::Engine, at: "/letter_opener"
end

Then visit http://localhost:3000/letter_opener, we will see your mails!

The author also provide a demo site for his gem, check it out http://letter-opener-web.herokuapp.com/