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

This worked for me

pdf = Prawn::Document.new(:page_size => "LETTER", :page_layout => :landscape)
pdf.render_file File.join(Rails.root, "app/pdfs", "x.pdf")
current_user.certificate = File.open("#{Rails.root}/app/pdfs/x.pdf")
current_user.save!

Where certificate is what my paperclip attachment is saved as in the model:

class User < ActiveRecord::Base
  has_attached_file :certificate

Answer 2

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.

Answer 3

I got it working without instance eval by turning it the other way around : generate the PDF in your model and render it in you controller

In a model :

  def generate_pdf
    Prawn::Document.new(:page_size => 'A4', :top_margin => 0, :left_margin => 0) do |pdf|
        <your pdf code here>
        <copy paste from your template>
    end.render
  end

You can then send it as a mail attachment :

attachment = generate_pdf
mail = Notifier.send_pdf(attachment)
mail.deliver

Or render it in your browser windows in your controller :

send_data your_model.generate_pdf, :type => "application/pdf", :disposition => 'inline'

Answer 4

@Adam Albrecht,You will be saving image as a attachment but for saving pdf as an attachment you need to add one more validation -

****validates_attachment :document, content_type: { content_type: 'application/pdf' }****

Answer 5

It should work if you just pass a File reference to that PDF to Paperclip.

require 'prawn'
pdf = Prawn::Document.new
pdf.text("Prawn Rocks")
pdf.render_file('/path/to/prawn.pdf')

pdf_file = File.open('/path/to/prawn.pdf')

# assuming your Paperclip association is named "pdf_attachment"
my_model.pdf_attachment = pdf_file