pdfkit.rb

Moonshine::PDFKit is a Moonshine plugin for installing and configuring PDFKit and WKHTMLToPDF.

 

      		
    

    

      
        

          
        

        
Prerequisites

      		
      
        

      		
    

    

      
        

          
        

        
We need to include any class level methods we need.
We’ll also need to configure some sane defaults for versions of the libraries.

      		
      
        
module Moonshine
  module PDFKit

    def self.included(manifest)
      manifest.class_eval do
        extend ClassMethods
        configure :pdfkit => { :version => '0.5.0' }
        configure :wkhtmltopdf => { :version => '0.9.9' }
      end
    end

    module ClassMethods
    end

      		
    

    

      
        

          
        

        
Recipe

      		
      
        

      		
    

    

      
        

          
        

        
We define the :pdfkit recipe which can take inline options.

      		
      
        
    def pdfkit(options = {})

      		
    

    

      
        

          
        

        
We ensure that the PDFKit gem is installed, and is either the version
the user specified, or the default version

      		
      
        
      gem 'pdfkit',
        :ensure => (options[:version] || configuration[:pdfkit][:version]),
        :require => exec('install_wkhtmltopdf')

      		
    

    

      
        

          
        

        
WKHTMLToPDF is required for PDFKit to work.
In order to install WKHTMLToPDFKit, we ensure we have met
its dependencies.

      		
      
        
      wkhtmltopdf_dependencies = %w(openssl build-essential xorg libssl-dev)
      wkhtmltopdf_dependencies.each do |pkg|
        package pkg, :ensure => :installed
      end

      		
    

    

      
        

          
        

        
WKHTMLToPDF provides different binaries depending on the arch, so
we use Facter to determine what arch the server is.

      		
      
        
      arch = case Facter.architecture
             when 'x86_64'
               'amd64'
             else
               'i386'
             end

      		
    

    

      
        

          
        

        
WKHTMLToPDF is provided in a precompiled tarball.



Before attempting to install it, we first check:



    

  • If it is currently installed
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  • If it is currently executable
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  • If the installed version is the version we want installed
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If neither of those conditions are met, then it wasn’t installed
or configured by this plugin, or the version is not the right one,
so we want to install it.



The installation process:



    

  • Navigates to the /tmp directory
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  • Cleans up any old tarballs
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  • Downloads WKHTMLToPDF
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  • Copies the pre-compiled binaries into place
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  • Ensures the binaries are executable
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      wkhtmltopdf_version = (options[:version] || configuration[:wkhtmltopdf][:version])

      exec 'install_wkhtmltopdf',
        :command => [ 
          'cd /tmp',
          'rm -f wkhtmltopdf*',
          "wget http://wkhtmltopdf.googlecode.com/files/wkhtmltopdf-#{wkhtmltopdf_version}-static-#{arch}.tar.bz2",
          "tar xvjf wkhtmltopdf-#{wkhtmltopdf_version}-static-#{arch}.tar.bz2",
          "mv wkhtmltopdf-#{arch} /usr/local/bin/wkhtmltopdf",
          'chmod +x /usr/local/bin/wkhtmltopdf'
          ].join(' && '),
        :onlyif => [ 
          'test ! -f /usr/local/bin/wkhtmltopdf',
          'test ! -x /usr/local/bin/wkhtmltopdf',
          "test `wkhtmltopdf --version | grep wkhtmltopdf | cut -d ' ' -f 4` != '#{wkhtmltopdf_version}'"
          ].join(' && '),
        :require => wkhtmltopdf_dependencies.map { |pkg| package(pkg) }
    end

  end
end