video-dl.rb

# このコードは　@taroyanaka様　が書いてくれた以下の記事をコピーし、必要な部分だけ残したものです。
# https://qiita.com/taroyanaka/items/c40f8d5df3ea67ba0b5a

require 'open3'

class Mediadl
  def initialize(file_name="./download_urls.txt")
    @file = file_name
  end

  def line_counter
    File.open(@file) do |f|
      while f.gets
        @total_lines = f.lineno
      end
    end
    return @total_lines
  end

  def dl
    counter = 0
    total_lines = self.line_counter
    File.open(@file,'r').each do |url|
      counter += 1
      puts "start file:#{counter}/#{total_lines}"
      Open3.capture3('youtube-dl -f mp4 ' + "#{url}")
      puts  "finish file:#{counter}/#{total_lines}"
    end
    Process.waitall
  end
end

download = Mediadl.new
download.dl