Save a Prawn PDF as a Paperclip attachment?

Question

I\'m using Prawn and Prawnto to display a PDF-based reports to the user, but in some circumstances, I\'d also like to save the PDF as an attachment to one of my models. I\'m usi

Answer 1

When using prawnto you will need to eval the variables in the .pdf.prawn template. Second step is to mimic a real file for paperclip.

1. Generating the PDF:

   #find the prawwnto template you want
   template = File.read("#{RAILS_ROOT}/app/views/reports/your_report.pdf.prawn")
   
   pdf = Prawn::Document.new(:page_size => 'A4', :your_options => :etc)
   
   pdf.instance_eval do
     @report = find_report #put here, all local variables that the pdf template needs
     eval(template) #this evaluates the template with your variables
   end
   
   attachment = pdf.render
   

2. Save PDF with paperclip:

   file = StringIO.new(attachment) #mimic a real upload file
   file.class.class_eval { attr_accessor :original_filename, :content_type } #add attr's that paperclip needs
   file.original_filename = "your_report.pdf"
   file.content_type = "application/pdf"
   
   
   #now just use the file object to save to the Paperclip association.
   
   
   # assuming your Paperclip association is named "pdf_report"
   @report_store.pdf_report = file
   @report_store.save!
   

Hope this helps.