Ruby script to generate a list of related articles.

nanoc_helper_related_articles.rb

require 'time'

# To generate related articles
def related_articles
  articles = []
  tm = DateTime.strptime(@item[:created_at], "%Y/%m/%d %H:%M:%S")
  if @item[:tags] != nil
    @item[:tags].each do |tag|
      @items.each do |item|
        if item[:kind] == "article" &&
           DateTime.strptime(item[:created_at], "%Y/%m/%d %H:%M:%S") < tm
          if item[:tags] != nil && item[:tags].include?(tag)
            articles << item unless articles.include?(item)
          end
        end
      end
    end

    # Sort by created_at
    articles.sort! {|a, b| b[:created_at] <=> a[:created_at]}
  end
  articles
end