jamendo downloader

jamendo_downloader.rb

#!/usr/bin/ruby

require 'rubygems'
require 'open-uri'
require 'json'
require 'ftools'
require 'cgi'
require 'optparse'

@download_dir = nil
@genre = nil
@top_num = nil
# move cursor to beginning of line
cr = "\r"
cwd = Dir.getwd
# ANSI escape code to clear line from cursor to end of line
# "\e" is an alternative to "\033"
# cf. http://en.wikipedia.org/wiki/ANSI_escape_code
clear = "\e[0K"

# reset lines
@reset = cr + clear

# if possible restore downloaded album_id array
begin
    @downloaded = JSON.parse(File.new('downloaded.json').read.gsub(/\t|\r/,''))
rescue
    @downloaded = []
end

# Add colorizing functionalities to String #####################################

class String
    def red; colorize(self, "\e[1m\e[31m"); end
    def green; colorize(self, "\e[1m\e[32m"); end
    def dark_green; colorize(self, "\e[32m"); end
    def yellow; colorize(self, "\e[1m\e[33m"); end
    def dark_yellow; colorize(self, "\e[33m"); end
    def blue; colorize(self, "\e[1m\e[34m"); end
    def dark_blue; colorize(self, "\e[34m"); end
    def pur; colorize(self, "\e[1m\e[35m"); end
    def colorize(text, color_code)  "#{color_code}#{text}\e[0m" end
end

################################################################################

# Functions ####################################################################

def download(genre,album,tracks_url)
    artist_name = album['artist_name']
    album_name  = album['name']
    album_id    = album['id']

    local_download_path = File.expand_path "#{@download_dir}/#{genre}/#{artist_name}/#{album_name}"
    File.makedirs local_download_path
    Dir.chdir local_download_path

    print "\n\n"
    puts "Going to download of \"#{album_name}\" by \"#{artist_name}\" finished".dark_blue
    counter = 1
    tracks_url.each do |url|
      print "#{@reset}downloading #{counter}/#{tracks_url.size}"
      $stdout.flush

      open(CGI.unescape(url.split(/\?/).first.split(/\//).last),"wb").write(open(url).read)
      counter +=1
    end

    @downloaded << album_id
    
    puts "\nDownload finished".green
end

################################################################################

# parse command line options ###################################################

opt = OptionParser.new
opt.banner = "Usage: run_tests [options]"

opt.on( "-h", "--help", "Print this message" ) do
  puts opt
  exit
end

opt.on( "-g", "--genre", "=GENRE_NAME", "download music of the specified genre" ) do |val|
  @genre = val
end

opt.on( "-d", "--download_dir", "=DONWLOAD_DIR", "place where the music files will be downloaded" ) do |val|
  @download_dir = val
end

opt.on( "-t", "=TOP_NUM", "download only TOP_NUM album of the specified genre " ) do |val|
  @top_num = val
end

begin
  opt.parse!( ARGV )
rescue OptionParser::InvalidOption
  puts $!
  puts opt
  exit
end

if ARGV.size > 0
  puts "Too many arguments"
  puts opt
  exit
end

if @genre.nil?
  puts 'You have to specify the genre'
  puts opt
  exit 1
end

if @top_num.nil?
  puts 'You have to specify the top num param'
  puts opt
  exit 1
end

if @download_dir.nil?
  @download_dir = "#{Dir.pwd}/downloaded_files"
  puts 'You have not specified the download dir'
  puts "Files will be download inside #{@download_dir}"
end

################################################################################

query_url = "http://api.jamendo.com/get2/id+name+artist_name/album/jsonpretty/?tag_idstr=#{@genre}&n=#{@top_num}&order=rating_desc"
query_url += "&idexclude=#{@downloaded.join('+')}" unless @downloaded.empty?

JSON.parse(open(query_url).read.gsub(/\t|\r/,'')).each do |album|
  album_download_urls = "http://www.jamendo.com/get/track/id/album/audio/plain/#{album['id']}/"
  
  tracks_url = []
  open(album_download_urls).each do |track_url|
    tracks_url << track_url.chomp
  end

  download(@genre, album, tracks_url)
end

Dir.chdir cwd
open('downloaded.json','w') { |f| f << @downloaded.to_json }