ActionMailer attachments in Ruby on Rails

If you use ActionMailer to send a lot of emails, at some point, you'll probably want to attach files to them. You might want to send a .pdf invoice to a customer, or attach custom images inline inside a newsletter email.Fortunately, ActionMailer makes attaching files really easy!In this article, I'll show you how to send emails with attachments using ActionMailer. We'll cover a few examples, including —attaching a .pdf file to an email,attaching multiple files,adding inline attachments for things like images,and specifying custom encodings for your attachments.