Module: Laze::Plugins::CacheBuster

Defined in:
lib/laze/plugins/cache_buster.rb

Overview

This plugin applies cache busters to CSS files, Javascript files and image files in your stylesheets. This means it will append the last modified time of these referenced files to the URL references as query parameters, so you force the server to bypass caches and give you a new file when a file has changed.

Example:

# css file
body {
  background: url(image.png);
}

# HTML file
<link href="screen.css">

Becomes:

# css file
body {
  background: url(image.png?201009231441);
}

# HTML file
<link href="screen.css?201009231441">

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.applies_to?(kind) ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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# File 'lib/laze/plugins/cache_buster.rb', line 30

def self.applies_to?(kind) #:nodoc:
  kind == 'Laze::Renderers::PageRenderer' || kind == 'Laze::Renderers::StylesheetRenderer'
end

Instance Method Details

#render(locals = {}) ⇒ Object 



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# File 'lib/laze/plugins/cache_buster.rb', line 34

def render(locals = {})
  Laze.info("Adding cache busters to #{options[:locals][:filename]}")
  [ /((?:href|src)=(?:'|"))(.+\.(?:css|js))("|')/,
    /(url\([\s"']*)([^\)"'\s]*\.(?:png|gif|jpg))([\s"']*\))/m
  ].inject(super) do |output, regex|
    output.gsub(regex) do |match|
      filename = File.expand_path(File.join('input', options[:locals][:path], $2))
      output = "#{$1}#{$2}%s#{$3}"
      cache_buster = File.exists?(filename) ? '?' + File.mtime(filename).strftime('%Y%m%d%H%M') : ''
      output % cache_buster
    end
  end
end