Configure a list of YouTube channels, and you can run this regularly to download new videos.

README.md

Configure a list of YouTube channels, and you can run this regularly to download new videos.

Creates .check-youtube folder in the user's home directory, where configuration and videos are stored. Example config.yml:

channels:
  - bluexephos
  - YogscastSips

Uses Ruby and the YouTube DL command-line utility.

check-youtube.rb

#! /usr/bin/ruby

require 'rubygems'
require 'json'
require 'open-uri'
require 'yaml'
require 'pty'

dir         = Dir.home() + '/.check-youtube'
config      = {'channels' => [], 'left_off_at' => {}}
config_file = dir + '/config.yml'

# Create folder if it doesn't exist
unless File.directory?(dir)
  `mkdir #{dir}`
  `mkdir #{dir}/videos`

  File.open(config_file, 'w') do |file|
    file.puts YAML::dump(config)
  end
end

# Load configuration and old data
config      = YAML::load(File.open(config_file))
channels    = config['channels'] || []
json_url    = 'https://gdata.youtube.com/feeds/base/users/%s/uploads?alt=json&orderby=published'
left_off_at = config['left_off_at'] || {}
new_videos_urls_total = []

# Check channels for new videos
channels.each do |channel|
  channel_json_url = json_url % channel
  videos = JSON.parse(open(channel_json_url).read)
  new_videos_urls = []

  videos['feed']['entry'].each do |video|
    if left_off_at.has_key?(channel) && video['id']['$t'] == left_off_at[channel]
      break
    end

    new_videos_urls << video['id']['$t']
  end

  if new_videos_urls.length > 0
    left_off_at[channel] = new_videos_urls.first
    new_videos_urls_total.concat new_videos_urls
  end
end

# Download new videos to folder
puts "Need to download %d videos" % new_videos_urls_total.length

new_videos_urls_total.each do |url|
  id = url.scan(/\/([^\/]+)\Z/).first.first
  puts "Working on #{id}..."

  # Download using youtube_dl
  begin
    PTY.spawn("youtube-dl --newline https://www.youtube.com/watch?v=#{id} -o \"#{dir}/videos/%(upload_date)s.%(title)s.%(ext)s\"") do |stdin, stdout, pid|
      begin
        # Output command progress in real-time
        stdin.each { |line| print line }
      rescue Errno::EIO
      end
    end
  rescue PTY::ChildExited
    "Done"
  end
end

# Save updated configuration
File.open(config_file, 'w') do |file|
  file.puts YAML::dump(config)
end