rails 3 中 生成pdf 2: email pdf 附件

ActionMailer in Rails 3

http://cn.asciicasts.com/episodes/206-actionmailer-in-rails3

在邮件中发送pdf附件,WickedPdf来做pdf生成，ActionMailer支持发送附件，只需使用attachments设置好pdf即可：

attachments["invoice.pdf"] = WickedPdf.new.pdf_from_string('<h1>Hello There!</h1>')

重点是要用render_to_string 来输出格式化好的pdf，但ActionMailer的render_to_string跟controller中的行为不是完全一致的，需要一点hack，完整实现如下：

class InvoiceMailer < ActionMailer::Base
  default :from => ApplicationSettings.email.sender_email
 
  def email_invoice(invoice)
    @invoice = invoice # set var for views
    attachments["#{invoice.file_name}.pdf"] = generate_pdf(invoice)
    mail(:to => invoice.bill_to_email, :subject => "#{invoice.company_name} Invoice")
  end
 
  protected

    # http://stackoverflow.com/questions/5421615/rails-3-actionmailer-and-wicked-pdf
    def generate_pdf(invoice)
      _controller_path = controller_path # backup the controller_path
      controller_path('invoices') # set controller_path PartialRenderer#find_template
      pdf = render_to_string(:layout => "pdf.html.haml", :template => "invoices/show.pdf.haml")
      controller_path(_controller_path) # reset the controller_path for current mailer
      # http://chopmode.wordpress.com/2011/03/25/render_to_string-causes-subsequent-mail-rendering-to-fail/
      self.instance_variable_set(:@lookup_context, nil) # enable mail() method could render the collect views
      pdf = WickedPdf.new.pdf_from_string(pdf)
    end

end