Lazy extract rar archives.

lazy_extract.rb

#!/usr/bin/env ruby
require "rubygems"
require "thor"
require "pty"

class LazyExtract < Thor

  desc "extract archive", "lazy extract an archive"
  method_option :password, :aliases => "-p", :desc => "Password for protected archives."
  method_option :verbose, :default => false, :aliases => "-v", :desc => "Print unrar output."
  def extract(archive)
    if !File.exists? archive
      puts "Archive not found. #{archive}"
      Process.exit
    end

    archiveName = "#{File.basename archive, ".part01.rar"}"
    targetDir = "#{File.dirname archive}/#{archiveName}"

    password = options[:password]
    cmd = "unrar x -vp -o+ "
    if password
      cmd += "-p#{password} "
    end
    cmd += "#{archive} #{targetDir}"

    if !File.directory?(targetDir)
      Dir.mkdir(targetDir)
    end

    puts cmd

    begin
      PTY.spawn(cmd) do |stdin, stdout, pid|
        begin
          
          done = false

          puts "Starting to extract."
          puts "Archive: #{archive}"
          puts "Target: #{targetDir}"

          chunk = 2

          last = ""

          stdin.each(1) do |char|
            last += char

            if options.verbose?
              putc char
            end

            if last =~ /\[C\]ontinue/
              puts "Waiting for part: #{chunk}"
              nextArchive = archive.gsub "part01", "part#{"%02d" % chunk}"
              while !File.exists? nextArchive
                sleep 1
              end
              puts "Found part #{chunk}."
              stdout.puts "C"
              chunk += 1
              last = ""
            end
          end
        rescue Errno::EIO
        end
      end
    rescue PTY::ChildExited
      puts "The child process exited!"
    end
  end
end
LazyExtract.start