Generate PDF from Rails

Question

The Ruby On Rails Wiki lists a couple of libraries that facilitate PDF generation in Rails. I need to print out address labels (in letter f

Answer 1

I've used flying saucer for pdf generation from html. It's a java library but you can use the Ruby-Java Bridge gem to access it in your rails app. It's css 2.1 compliant and has a few additions from css3 to allow some extra control over paging. I'd recommend it as it doesn't require you to put 'pdf code' in your html, you can use the same views and partials to display to the browser as you do to generate pdfs.

Flying Saucer: https://github.com/flyingsaucerproject/flyingsaucer

Ruby Java Bridge: http://rjb.rubyforge.org/

I use this module code to generate the pdfs

require 'rubygems'
require 'rjb'

module Html2Pdf

  def self.included(controller)
      controller.send :helper_method, :create_pdf
  end

  def create_pdf(options = {})
      itext = "#{RAILS_ROOT}/lib/html2pdf/jars/iText-2.0.8.jar"
      core_renderer = "#{RAILS_ROOT}/lib/html2pdf/jars/core-renderer.jar"
      xerces = "#{RAILS_ROOT}/lib/html2pdf/jars/xml-apis-xerces-2.9.1.jar" 
      joinchar = (RUBY_PLATFORM.include? 'mswin') ? ';' : ':'
          classpath = [itext, core_renderer, xerces].join(joinchar)
      Rjb::load(classpath, jvmargs=['-Djava.awt.headless=true'])
      if options[:htmlstring].nil?
      options[:layout] ||= false
          options[:template] ||= File.join(controller_path,action_name+".pdf.erb")
          html_string = render_to_string(:template => options[:template], :layout => options[:layout])
    else
          html_string = options[:htmlstring]
    end
    # Make all paths relative, on disk paths...
    html_string.gsub!(".com:/",".com/") # strip out bad attachment_fu URLs
    html_string.gsub!( /src=["']+([^:]+?)["']/i ) { |m| "src=\"file:///#{RAILS_ROOT}/public/" + $1 + '"' } # re-route absolute paths
    html_string.gsub!( /url\(["']+([^:]+?)["']/i ) { |m| "url\(\"file:///#{RAILS_ROOT}/public/" + $1 + '"' } # re-route absolute paths
    # Remove asset ids on images with a regex // tbh i can't remember what this line is for but i'm sure it did something awesome
    html_string.gsub!( /src=["'](\S+\?\d*)["']/i ) { |m| 'src="' + $1.split('?').first + '"' } 
    filename = "#{RAILS_ROOT}/public/pdfs/"+options[:filename]+".pdf"
    fileOutputStream = Rjb::import('java.io.FileOutputStream')
      iTextRenderer = Rjb::import('org.xhtmlrenderer.pdf.ITextRenderer')
      renderer = iTextRenderer.new
      renderer.setDocumentFromString(html_string)
      os = fileOutputStream.new(filename)
      renderer.layout()
      renderer.createPDF(os)
      os.close()
  end

end

Calling it with code like this:

def generate_pdf  
  htmlsrc = render_to_string(:partial => 'invoice', :layout => false)
  rnd = Time.now.to_s(:datentime).gsub!(/[\/ \.:]/,'')
  filename = "docstore/tmp_#{rnd}"
  create_pdf(:htmlstring => htmlsrc, :filename => filename)
  contents = open("#{RAILS_ROOT}/public/pdfs/#{filename}.pdf", "rb") { |io| io.read }
  File.delete("#{RAILS_ROOT}/public/pdfs/#{filename}.pdf")
  respond_to do | wants |
    wants.html { render :text => contents, :content_type => 'application/pdf' }
  end    
end

Answer 2

Prawn is the way to go. Now with prawn-labels that is really easy to do.

Check out the project's README here:

https://github.com/jordanbyron/prawn-labels#readme

This is a super simple example being used in a Rails controller. Don't forget to add gem 'prawn-labels' to your Gemfile.

names = %w{Jordan Kelly Greg Bob}

labels = Prawn::Labels.render(names, :type => "Avery5160") do |pdf, name|
  pdf.text name
end

send_data labels, :filename => "names.pdf", :type => "application/pdf"

Answer 3

There's also RTeX. That works well if you're willing to translate to LaTeX first. LaTeX is a very good way to store marked-up documents. It just depends on how static each document is. If most of the document is dynamic, you might do better with Prawn or PDF::Writer. If most of it is static, with just a couple of text-replacements for each, LaTeX might be a better choice.

Answer 4

There is also PDFKit. It's quite interesting too.

Answer 5

The best I've seen so far is Prawn:

• Prawn http://prawn.majesticseacreature.com/
• http://advent2008.hackruby.com/past/2008/12/17/awn_and_the_future_of_ruby_pdf_generation/
• http://railstips.org/2008/10/14/how-to-generate-pdfs-in-rails-with-prawn
• Prawn Rails plugin: http://www.cracklabs.com/prawnto

Answer 6

Prawn with Prawnto for sure. The DSL is a real treat, as is the simplicity of being able to treat PDF as any other format in a respond_to format block:

respond_to do |format|
format.pdf { render :layout => false }

There's a tutorial video on Prawn here: