packingslip.rb

# coding: utf-8

class PackingSlip < Prawn::Document
  # recognized options
  # :needs_cover_page => true|false
  def initialize(orders, options = {})
    super(:page_layout => :portrait)
    @orders  = orders
    @options = options

    default_leading 5

    cover_page if cover_page_needed?

    @orders.each do |order|
      order_page(order)
      start_new_page unless order == orders.last
    end
  end

  # ...

end

Can you please also include the structure of order_page(order) here ?

Would make it complete ?