Preview email in the browser instead of sending it. This means you do not need to set up email delivery in your development environment, and you no longer need to worry about accidentally sending a test email to someone else's address.
First add the gem to your development environment and run the bundle command to install it.
gem "letter_opener", :group => :development
Then set the delivery method in config/environments/development.rb
config.action_mailer.delivery_method = :letter_opener
Now any email will pop up in your browser instead of being sent. The messages are stored in tmp/letter_opener.
Non Rails Setup
If you aren't using Rails, this can be easily set up with the Mail gem. Just set the delivery method when configuring Mail and specify a location.
require "letter_opener" Mail.defaults do delivery_method LetterOpener::DeliveryMethod, :location => File.expand_path('../tmp/letter_opener', __FILE__) end
Alternatively, if you are using ActionMailer directly (without Rails) you will need to add the delivery method.
require "letter_opener" ActionMailer::Base.add_delivery_method :letter_opener, LetterOpener::DeliveryMethod, :location => File.expand_path('../tmp/letter_opener', __FILE__) ActionMailer::Base.delivery_method = :letter_opener
Letter Opener uses Launchy to open sent mail in the browser. This assumes the Ruby process is running on the local development machine. If you are using a separate staging server or VM this will not work. In that case consider using Mailtrap or MailCatcher.
In order to keep this project simple, I don't have plans to turn it into a Rails engine with an interface for browsing the sent mail. However it would be awesome if someone wants to release that as a separate gem, perhaps called remote_letter_opener.
Development & Feedback
Questions or problems? Please use the issue tracker. If you would like to contribute to this project, fork this repository and run bundle and rake to run the tests. Pull requests appreciated.