Rails - ActionMailer - How to send an attachment that you create?

Question

In rails3 w ActionMailer, I want to send a .txt file attachment. The challenge is this txt file does not exist but rather I want to create the txt file given a large block o

Answer 1

It's described for files in the API documentation of ActionMailer::Base

class ApplicationMailer < ActionMailer::Base
  def welcome(recipient)
    attachments['free_book.pdf'] = File.read('path/to/file.pdf')
    mail(:to => recipient, :subject => "New account information")
  end
end

But that doesn't have to be a File, it can be a string too. So you could do something like (I'm also using the longer Hash-based form where you can specify your own mimetype too, you can find documentation for this in ActionMailer::Base#attachments):

class ApplicationMailer < ActionMailer::Base
  def welcome(recipient)
    attachments['filename.jpg'] = {:mime_type => 'application/mymimetype',
                                   :content => some_string }
    mail(:to => recipient, :subject => "New account information")
  end
end