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Global Captures

This plugin allows you to capture content on one page and use it on any other page. Please see write up here: http://www.dseifert.net/archive/2008-09/.

Usage

Add the source below to your lib directory as, say, lib/global_captures.rb.

Then, on the page that has the global content, wrap the content as follows:


<% global_content_for :foo do %>
This is the FOO stuff.
<% end %>


Everything in the block will be captured and saved under the global tag :foo.

Then, in any page you want to see the :foo content, just use markup like the following.


<%= global_content_for :foo %>


Source


module Nanoc
  #Raised in the event of an unsatisified global capture dependency
  class UnsatisfiedGlobalCaptureReference < StandardError
  end
  class Compiler
    attr_accessor :recompiles
    alias :old_run :run
    def run(objects = nil, params = {})
      # Track recursion depth.  We allow a depth of no more
      # than 2. If greater, we have unsatisfied global capture
      # references
      (@depth ||= 0)
      @depth += 1
      if @depth > 2
        raise UnsatisfiedGlobalCaptureReference.new("The following pages have unsatisfied global capture references: #{@recompiles.join(', ')}") 
      end
     
      @recompiles = []
      old_run(objects, params)

      # Recompile stuff that had a global capture miss
      recompile_pages = @recompiles.map do |path|
        @site.pages.find do |site_page|
          check_path = path.gsub('.html', '/')
          site_page.path == check_path
        end
      end
      if recompile_pages.size > 0
        run(recompile_pages, :also_layout => params[:also_layout], :even_when_not_outdated => true, :from_scratch => true)
      end
    end  
  end
end

module GlobalCapturing
  CAPTURES = {}
  def global_content_for(name, &block)
    if !block.nil?
      global_captures[name] = global_capture(&block)
    end
    if !global_captures.has_key?(name)
      # TODO: Is this possible
      # Need to somehow signal the compiler that this page should be skipped for now
      # HACK: For some reason '==' does not work on @page objects, so use the path as the
      # equality check
      @site.compiler.recompiles << @page.path
    end
    global_captures[name]
  end

  def global_captures
    CAPTURES
  end

  private

  def global_capture(*args, &block)
    buffer = eval('_erbout', block.binding)

    pos = buffer.length
    block.call(*args)

    data = buffer[pos..-1]

    buffer[pos..-1] = ''

    data
  end
end

include GlobalCapturing