How to edit or write on existing PDF with Ruby?

Question

I have a couple of PDF template files with complex content and several blank regions/areas in them. I need to be able to write text in those blank regions and save the resul

Answer 1

Since Prawn has removed the template feature (it was full of bugs) the easiest way I've found is the following:

1. Use Prawn to generate a PDF with ONLY the dynamic parts you want to add.
2. Use PDF::Toolkit (which wraps PDFtk) to combine the Prawn PDF with the original.

Rough Example:

require 'prawn'
require 'pdf/toolkit'

template_filename = 'some/dir/Awesome-Graphics.pdf'
prawn_filename = 'temp.pdf'
output_filename = 'output.pdf'

Prawn::Document.generate(prawn_filename) do
  # Generate whatever you want here.
  text_box "This is some new text!", :at => [100, 300]
end

PDF::Toolkit.pdftk(prawn_filename, "background", template_filename, "output", output_filename)