add pagination to YouTube Model

youtube_paginate.rb

YouTubeModel::SingletonMethods.class_eval do
  include WillPaginate::Finders::Base

  protected

  def wp_query(options, pager, args)
    # dup options and set limit
    args << options.merge(:max_results => pager.per_page)
    # carefully add start_index (YouTube goes nuts if it's zero)
    args.last[:start_index] = pager.offset if pager.offset > 0
    # perform the search
    youtube = send(:find, *args)
    # populate the collection with videos
    pager.replace youtube.videos
    # keep track of total results
    unless pager.total_entries
      pager.total_entries = youtube.totalResults.to_i
    end
  end
end