PDF export from a Model method using render_to_string

Question

I need to implement a _to_pdf method on my ProjectBill model which generates a PDF of my bill at this place:

/public/xls/bills/project_#{project.number}_bill_#{bill.number}.pdf

My application is using HTMLDoc for generating PDF. I am using Rails 2.3.11. With the HTMLDoc gem, I need to pass a render_to_string of my partial view _bill.pdf.haml, wich is not accessible in the model (only in the controllers), to HTMLDoc.

I already have an export_to_pdf action in my controller, triggered by the user when he wants an export (this one works). The model method will be called by a scheduled task, an emailer sending the bills when the scheduled_date is equal to Date.today.

I've already tried tons of solutions:

• http://www.omninerd.com/articles/render_to_string_in_Rails_Models_or_Rake_Tasks/print_friendly
• Have a to_pdf action on my ProjectBill controller and call it in from Model (but not working, saying that render_to_string is not defined even if its called in the Controller)
• Use my working export_to_pdf method with a get request sent from my Model (but I figured out that I cannot really send a request from a Model...)
• Use a Helper with the render_to_string inside it (not working: undefined method)
• and even more !

But still not working.

Can somebody help me with this issue? Im stuck and can't find any solution...

Answer 1

Ahh I finally did it !

Thanks for your answer Sean but I was not looking for a better Gem, I was looking for a solution to my issue.

For some reason I couldn't use the render_to_string method in my Model... So I created my export_to_pdf method on my model:

  def export_to_pdf
    bill = self
    project = self.project

    path = "facture_#{self.project.id}_#{self.bill_number}_#{Date.today.strftime('%Y_%m_%d')}.pdf"

    Plus::BillingItemsController.new._to_pdf(bill.id)

    if File.exists?(path)
      return path
    else
      return nil
    end
  end

As you can see I call my Controller in my Model. Here is my _to_pdf method:

 def _to_pdf(bill_id)
    @bill = Plus::ProjectBill.find_by_id(bill_id)
    @project = @bill.project
    path = "#{RAILS_ROOT}/public/xls/facture_#{@project.id}_#{@bill.bill_number}_#{Date.today.strftime('%Y_%m_%d')}.pdf"

    av = ActionView::Base.new(Rails::Configuration.new.view_path)
    av.class_eval do
      include ApplicationHelper
      include ActionController::UrlWriter
      default_url_options[:host] = 'mysite.com'
    end

    av.extend ApplicationController.master_helper_module
    html = av.render(:partial => "/plus/billing_items/bill_for_pdf.haml", :locals => {:bill => @bill})
    data = to_pdf(html, false, {:header => '', :headfootsize => 0, :outfile => path})
  end

My to_pdf function is just doing the PDF::HTMLDoc.new and the set_option of links, logoimage , etc. and return pdf.generate

I hope this can help someone someday somewhere !