"Dammit, I can't believe Picasa requires me to download photos one by one. Someone needs to do something about that."

picasaweb_download_client.rb

#!/usr/bin/env ruby

require "net/http"
require "rexml/document"

class PicasawebDownloadClient

  PICASAWEB = "picasaweb.google.com"

  # Will return a list of links to every photo in an album
  # 
  # Let's go DOM spelunking.
  def find_links_for_album(googleUser, picasaAlbum, authkey = nil)
    httpnet = Net::HTTP.new(PICASAWEB, 80)
    httpnet.start do |http|
      url = "/data/feed/api/user/#{googleUser}/album/#{picasaAlbum}?kind=photo"
      url = url + "&authkey=#{authkey}" unless authkey.nil?
      request = Net::HTTP::Get.new(url)
      response = http.request(request)
      response.value
      #File.open("xml.data", "w") {|x| x.write response.body }
      root = REXML::Document.new(response.body).root
      list = root.elements.collect("//entry/media:group/media:content") {|x| x.attributes["url"]}
    end
  end
end

if __FILE__ == $0
  if ARGV.length == 0 
    puts "Generate curl statements that will download all photos in a Picasa photo album\n\nUsage: #{__FILE__} user album [authkey] | sh" 
    exit
  end
  user, album, authkey = ARGV[0], ARGV[1], ARGV[2]
  # puts "Downloading #{user}/#{album} (authkey = #{authkey})"
  
  list = PicasawebClient.new.find_links_for_album(user, album, authkey)
  list.each {|x| puts "curl -O #{x}"}
end