Wicked PDF 
A PDF generation plugin for Ruby on Rails
Wicked PDF uses the shell utility wkhtmltopdf to serve a PDF file to a user from HTML. In other words, rather than dealing with a PDF generation DSL of some sort, you simply write an HTML view as you would normally, then let Wicked take care of the hard stuff.
Wicked PDF has been verified to work on Ruby 1.8.7 and 1.9.2; Rails 2 and Rails 3
Installation
First, be sure to install wkhtmltopdf. If your wkhtmltopdf executable is not on your webserver's path, configure it in an initializer: WickedPdf.config = { :exe_path => '/usr/local/bin/wkhtmltopdf' } Note that versions before 0.9.0 have problems on some machines with reading/writing to streams. This plugin relies on streams to communicate with wkhtmltopdf.
More information about wkhtmltopdf could be found here.
Next:
script/plugin install git://github.com/mileszs/wicked_pdf.git
script/generate wicked_pdf
or add this to your Gemfile:
gem 'wicked_pdf'
You may also need to add Mime::Type.register "application/pdf", :pdf to config/initializers/mime_types.rb
Basic Usage
class ThingsController < ApplicationController
def show
respond_to do |format|
format.html
format.pdf do
render :pdf => "file_name"
end
end
end
end
Advanced Usage with all available options
class ThingsController < ApplicationController
def show
respond_to do |format|
format.html
format.pdf do
render :pdf => 'file_name',
:disposition => 'attachment', # default 'inline'
:template => 'things/show.pdf.erb',
:layout => 'pdf.html', # use 'pdf.html' for a pdf.html.erb file
:wkhtmltopdf => '/usr/local/bin/wkhtmltopdf', # path to binary
:show_as_html => params[:debug].present?, # allow debuging based on url param
:orientation => 'Landscape', # default Portrait
:page_size => 'A4, Letter, ...', # default A4
:save_to_file => Rails.root.join('pdfs', "#{filename}.pdf"),
:save_only => false, # depends on :save_to_file being set first
:proxy => 'TEXT',
:basic_auth => false # when true username & password are automatically sent from session
:username => 'TEXT',
:password => 'TEXT',
:cover => 'URL',
:dpi => 'dpi',
:encoding => 'TEXT',
:user_style_sheet => 'URL',
:cookie => ['_session_id SESSION_ID'], # could be an array or a single string in a 'name value' format
:post => ['query QUERY_PARAM'], # could be an array or a single string in a 'name value' format
:redirect_delay => NUMBER,
:zoom => FLOAT,
:page_offset => NUMBER,
:book => true,
:default_header => true,
:disable_javascript => false,
:grayscale => true,
:lowquality => true,
:enable_plugins => true,
:disable_internal_links => true,
:disable_external_links => true,
:print_media_type => true,
:disable_smart_shrinking => true,
:use_xserver => true,
:no_background => true,
:extra => '' # directly inserted into the command to wkhtmltopdf
:margin => {:top => SIZE, # default 10 (mm)
:bottom => SIZE,
:left => SIZE,
:right => SIZE},
:header => {:html => { :template => 'users/header.pdf.erb', # use :template OR :url
:layout => 'pdf_plain.html', # optional, use 'pdf_plain.html' for a pdf_plain.html.erb file, defaults to main layout
:url => 'www.example.com',
:locals => { :foo => @bar }},
:center => 'TEXT',
:font_name => 'NAME',
:font_size => SIZE,
:left => 'TEXT',
:right => 'TEXT',
:spacing => REAL,
:line => true,
:content => 'HTML CONTENT ALREADY RENDERED'}, # optionally you can pass plain html already rendered (useful if using pdf_from_string)
:footer => {:html => { :template => 'shared/footer.pdf.erb', # use :template OR :url
:layout => 'pdf_plain.html', # optional, use 'pdf_plain.html' for a pdf_plain.html.erb file, defaults to main layout
:url => 'www.example.com',
:locals => { :foo => @bar }},
:center => 'TEXT',
:font_name => 'NAME',
:font_size => SIZE,
:left => 'TEXT',
:right => 'TEXT',
:spacing => REAL,
:line => true,
:content => 'HTML CONTENT ALREADY RENDERED'}, # optionally you can pass plain html already rendered (useful if using pdf_from_string)
:toc => {:font_name => "NAME",
:depth => LEVEL,
:header_text => "TEXT",
:header_fs => SIZE,
:l1_font_size => SIZE,
:l2_font_size => SIZE,
:l3_font_size => SIZE,
:l4_font_size => SIZE,
:l5_font_size => SIZE,
:l6_font_size => SIZE,
:l7_font_size => SIZE,
:l1_indentation => NUM,
:l2_indentation => NUM,
:l3_indentation => NUM,
:l4_indentation => NUM,
:l5_indentation => NUM,
:l6_indentation => NUM,
:l7_indentation => NUM,
:no_dots => true,
:disable_links => true,
:disable_back_links => true},
:outline => {:outline => true,
:outline_depth => LEVEL}
end
end
end
end
By default, it will render without a layout (:layout => false) and the template for the current controller and action.
Super Advanced Usage
If you need to just create a pdf and not display it:
# create a pdf from a string
pdf = WickedPdf.new.pdf_from_string('<h1>Hello There!</h1>')
# create a pdf from string using templates, layouts and content option for header or footer
WickedPdf.new.pdf_from_string(
render_to_string(:pdf => "pdf_file.pdf", :template => 'templates/pdf.html.erb', :layout => 'pdfs/layout_pdf'),
:footer => {:content => render_to_string({:template => 'templates/pdf_footer.html.erb', :layout => 'pdfs/layout_pdf'})}
# or from your controller, using views & templates and all wicked_pdf options as normal
pdf = render_to_string :pdf => "some_file_name"
# then save to a file
save_path = Rails.root.join('pdfs','filename.pdf')
File.open(save_path, 'wb') do |file|
file << pdf
end
If you need to display utf encoded characters, add this to your pdf views or layouts:
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
Styles
You must define absolute paths to CSS files, images, and javascripts; the best option is to use the wicked_pdf_stylesheet_link_tag, wicked_pdf_image_tag, and wicked_pdf_javascript_include_tag helpers.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<%= wicked_pdf_stylesheet_link_tag "pdf" -%>
<%= wicked_pdf_javascript_include_tag "number_pages" %>
</head>
<body onload='number_pages'>
<div id="header">
<%= wicked_pdf_image_tag 'mysite.jpg' %>
</div>
<div id="content">
<%= yield %>
</div>
</body>
</html>
Page Numbering
A bit of javascript can help you number your pages. Create a template or header/footer file with this:
<html>
<head>
<script>
function number_pages() {
var vars={};
var x=document.location.search.substring(1).split('&');
for(var i in x) {var z=x[i].split('=',2);vars[z[0]] = unescape(z[1]);}
var x=['frompage','topage','page','webpage','section','subsection','subsubsection'];
for(var i in x) {
var y = document.getElementsByClassName(x[i]);
for(var j=0; j<y.length; ++j) y[j].textContent = vars[x[i]];
}
}
</script>
</head>
<body onload="number_pages()">
Page <span class="page"></span> of <span class="topage"></span>
</body>
</html>
Anything with a class listed in "var x" above will be auto-filled at render time.
If you do not have explicit page breaks (and therefore do not have any "page" class), you can also use wkhtmltopdf's built in page number generation by setting one of the headers to "[page]":
render :pdf => 'filename', :header => { :right => '[page] of [topage]' }
Configuration
You can put your default configuration, applied to all pdf's at "wicked_pdf.rb" initializer.
Further Reading
Andreas Happe's post Generating PDFs from Ruby on Rails
StackOverflow questions with the tag "wicked-pdf"
Debugging
Now you can use a debug param on the URL that shows you the content of the pdf in plain html to design it faster.
First of all you must configure the render parameter ":show_as_html => params[:debug]" and then just use it like normally but adding "debug=1" as a param:
http://localhost:3001/CONTROLLER/X.pdf?debug=1
However, the wicked_pdf_* helpers will use file:// paths for assets when using :show_as_html, and your browser's cross-domain safety feature will kick in, and not render them. To get around this, you can load your assets like so in your templates:
<%= params[:debug].present? ? image_tag('foo') : wicked_pdf_image_tag('foo') %>
Inspiration
You may have noticed: this plugin is heavily inspired by the PrinceXML plugin princely. PrinceXML's cost was prohibitive for me. So, with a little help from some friends (thanks jqr), I tracked down wkhtmltopdf, and here we are.
Awesome Peoples
Also, thanks to unixmonkey, galdomedia, jcrisp, lleirborras, tiennou, and everyone else for all their hard work and patience with my delays in merging in their enhancements.