railscast downloader

downloader.rb

require 'rubygems'
require 'nokogiri'
require 'open-uri'

doc = Nokogiri::HTML(open("http://railscasts.com/?type=free"))
total_pages = doc.css('.pagination a:nth-last-child(2)').inner_html.to_i

(1..total_pages).each do |i|
  puts "PAGE #{i} ================================"
  
  doc = Nokogiri::HTML(open("http://railscasts.com/?type=free&page=#{i}"))
  
  doc.css('.episode').each do |episode|
    href  = episode.css('.watch a:first-child')[0]['href'].split('?')[0]
    filename = href.split('/').last + '.m4v'
    download_url = "/assets/episodes/videos/#{filename}"
    filepath = File.dirname(__FILE__) + "/videos/" + filename
    
    unless File.exist?(filepath)
      puts "Downloading #{filename}"
      Net::HTTP.start('media.railscasts.com', 80) { |http|
        resp = http.get(download_url)
        open(filepath, "wb") { |file|
          file.write(resp.body)
        }
      }
    end
  end
  
  puts "================================"
end