bin/whatever-dl

   1 #!/usr/bin/ruby -wKU
   2 #
   3 # whatever-dl, a script to download online (web-based) videos.
   4 #
   5 # Copyright Michael Orlitzky
   6 #
   7 # http://michael.orlitzky.com/
   8 #
   9 # This program is free software: you can redistribute it and/or modify
  10 # it under the terms of the GNU General Public License as published by
  11 # the Free Software Foundation, either version 3 of the License, or
  12 # (at your option) any later version.
  13 #
  14 # This program is distributed in the hope that it will be useful,
  15 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17 # GNU General Public License for more details.
  18 #
  19 # http://www.fsf.org/licensing/licenses/gpl.html
  20 #
  21
  22 # We need Pathname to get the real filesystem path
  23 # of this script (and not, for example, the path of
  24 # a symlink which points to it.
  25 require 'pathname'
  26
  27 # And getoptlong to check for our one option, --continue.
  28 require 'getoptlong'
  29
  30 # This bit of magic adds the parent directory (the
  31 # project root) to the list of ruby load paths.
  32 # Thus, our require statements will work regardless of
  33 # how or from where the script was run.
  34 executable = Pathname.new(__FILE__).realpath.to_s
  35 $: << File.dirname(executable) + '/../'
  36
  37 # Load our config file.
  38 require 'bin/configuration'
  39
  40 # And the downloaders...
  41 require 'src/downloader'
  42
  43 # The Dir.glob that's coming up doesn't use the
  44 # Ruby library path so we need to tell it where to
  45 # look explicitly.
  46 websites_pattern = File.dirname(executable) + '/../src/websites/*.rb'
  47
  48 # All of the website classes are located in one
  49 # directory, so we can 'require' them automatically.
  50 Dir.glob(websites_pattern).each do |r|
  51   require r
  52 end
  53
  54
  55 EXIT_SUCCESS = 0
  56 EXIT_NO_URL = 1
  57 EXIT_INVALID_URL = 2
  58 EXIT_COULDNT_GET_VIDEO_URL = 3
  59 EXIT_IO_ERROR = 4
  60 EXIT_ERROR_READING_FROM_VIDEO_URL = 5
  61 EXIT_CONNECTION_REFUSED = 6
  62 EXIT_HTTP_ERROR = 7
  63 EXIT_ACCESS_DENIED = 8
  64
  65 def usage()
  66   puts <<EOF
  67
  68 Usage: whatever-dl [options] <url>
  69
  70 Options:
  71   -c, --continue        Continue downloading a previously-attempted file.
  72
  73 EOF
  74
  75 end
  76
  77 # Only actually do something if this script was called
  78 # directly (i.e. not from the tests).
  79 if (__FILE__ == $0) then
  80   # Default options.
  81   options = { :continue => false }
  82
  83   # Parse the command-line options into the options hash.
  84   opts = GetoptLong.new(["--continue", "-c", GetoptLong::NO_ARGUMENT],
  85                         ["--help", "-h", GetoptLong::NO_ARGUMENT])
  86
  87   opts.each do |opt, arg|
  88     case opt
  89     when '--help'
  90       usage()
  91       Kernel.exit(EXIT_SUCCESS)
  92     when '--continue'
  93       options[:continue] = true
  94     end
  95   end
  96
  97   # Warn about nonsensical options.
  98   if options[:continue] and not (Configuration::DOWNLOAD_METHOD == :wget)
  99     puts 'WARNING: The --continue flag does nothing unless DOWNLOAD_METHOD is :wget.'
 100   end
 101
 102   # Note that GetoptLong steals its arguments from ARGV, so we don't need
 103   # to take optional arguments into account when figuring out whether or not
 104   # we were passed a URL.
 105   if (ARGV.length < 1) then
 106     # If the user didn't give us a URL, yell
 107     # at him or her.
 108     usage()
 109     Kernel.exit(EXIT_NO_URL)
 110   end
 111
 112   # Factory method.
 113   site = Website.create(ARGV[0])
 114
 115   if site.nil?
 116     puts 'Invalid URL.'
 117     exit(EXIT_INVALID_URL)
 118   end
 119
 120   video_url = site.get_video_url()
 121
 122   if video_url.nil?
 123     puts 'Error retrieving video URL.'
 124     exit(EXIT_COULDNT_GET_VIDEO_URL)
 125   end
 126
 127   # The Downloader class is a factory; it should decide
 128   # which subclass we get.
 129   downloader = Downloader.create(Configuration::DOWNLOAD_METHOD)
 130
 131   # Attempt to download the file, and rescue and report
 132   # any (predictable) exceptions. The wget downloader will
 133   # naturally not report any of these, since it will die in
 134   # its own process.
 135   begin
 136     downloader.download(video_url,
 137                         site.get_video_filename(),
 138                         site.headers(),
 139                         continue=options[:continue])
 140   rescue Errno::ECONNREFUSED => e
 141     puts 'The connection to the server (to download the video file) was refused. Check your connection, and try again later.'
 142     Kernel.exit(EXIT_CONNECTION_REFUSED)
 143   rescue Errno::EACCES => e
 144     puts "Access denied. Check that you have write permission to the output file/directory. Details: #{e.message}."
 145   rescue OpenURI::HTTPError => e
 146     puts "An HTTP error occurred while downloading the video file: #{e.message}."
 147     Kernel.exit(EXIT_HTTP_ERROR)
 148   rescue IOError => e
 149     puts "Input/Output Error: #{e.message}"
 150     Kernel.exit(EXIT_IO_ERROR)
 151   end
 152
 153   # Write an empty line at the end for aesthetic reasons.
 154   puts ''
 155
 156   Kernel.exit(EXIT_SUCCESS)
 157 end