refer to: https://api.rubyonrails.org/classes/ActionMailer/Base.html
class NotifierMailer < ApplicationMailer
def welcome(recipient)
attachments["free_book.pdf"] = File.read("path/to/file.pdf")
mail(to: recipient,
subject: "New account information",
content_type: "text/html",
body: "Hello there")
end
endd
动态内容
https://stackoverflow.com/questions/18591126/rails-mailer-custom-dynamic-content
还是需要用view. 在view中, 使用 <%= raw @dynamic_content %> 即可。
然后在mailer 中, (忽略没写完的from)

使用附件
都是上面