render-an-alternative-action-mailer-template.md

Render An Alternative ActionMailer Template

The convention for Rails's ActionMailer is to render the view template that corresponds to the mailer class's name and the specific action.

For instance, the welcome_email method in the RegistrationMailer class will correspond to the app/views/registration_mailer/welcome_email.html.erb view.

This convention can be overridden. By passing, the template_name and template_path arguments as options to the mail method, you can tell the mailer to render a different template.

class RegistrationMailer < ActionMailer::Base
  def welcome_email
    # mail setup ...

    mail(to: @user.email,
        subject: 'Welcome!',
        template_name: 'new_welcome')
  end
end

This will look for and use the app/views/registration_mailer/new_welcome.html.erb template.

Also including the template_path option will alter the path to the named template:

class RegistrationMailer < ActionMailer::Base
  def welcome_email
    # mail setup ...

    mail(to: @user.email,
        subject: 'Welcome!',
        template_path: 'v2_mailer_templates',
        template_name: 'new_welcome')
  end
end

This will look for the app/views/v2_mailer_templates/new_welcome.html.erb template.

source