To generate a new mailer, enter the following command
rails generate mailer PostMailer
This will generate a blank template file in app/mailers/post_mailer.rb
named PostMailer
class PostMailer < ApplicationMailer
end
Two layout files will also be generated for the email view, one for the html format and one for the text format.
If you prefer not to use the generator, you can create your own mailers. Make sure they inherit from ActionMailer::Base