A YouTube example container for discordrb

youtube.rb

# frozen_string_literal: true

# Use `bot.include! YouTubeContainer` to use this in your CommandBot
# This requires you to have youtube-dl installed as well as other voice prerequisites.
#
# This example is extremely slow, but could potentially be sped up if the youtube-dl
# `-o -` option actually worked. If you can get it to work, hit me up because other people's
# older examples always fail when I run them locally.

require 'discordrb'

module YouTubeContainer
  extend Discordrb::Commands::CommandContainer

  # This regex is used to validate that we're actually trying to play a video
  # The base regex, before I made it non capturing, is from this stack overflow answer
  # https://stackoverflow.com/a/41029451
  YOUTUBE_URL = /^(?:http(s)??\:\/\/)?(?:www\.)?(?:(?:youtube\.com\/watch\?v=)|(?:youtu.be\/))(?:[a-zA-Z0-9\-_])+/
  YOUTUBE_DL_OPTIONS = '--no-playlist --extract-audio --max-filesize 50M --audio-format vorbis'

  command :yt do |event, url|
    unless url =~ YOUTUBE_URL
      return 'This is not a valid youtube url'
    end

    unless event.author.voice_channel
      return 'You must be in a voice channel to use this command'
    end

    voice_bot = event.bot.voice(event.server)
    voice_bot ||= event.bot.voice_connect(event.author.voice_channel)

    Dir.mktmpdir("#{event.server.id}-yt") do |dir|
      result = `youtube-dl #{YOUTUBE_DL_OPTIONS} -o \"#{dir}/%(title)s.%(ext)s\" #{url}`
      title = `youtube-dl --get-filename -o \"%(title)s\" #{url}`.chomp
      
      return 'There was an issue downloading this song' unless title


      event.send_embed do |embed|
        embed.title = 'YouTube'
        embed.description = title
      end

      10.times { sleep 1 unless File.exist? "#{dir}/#{title}.ogg" }

      voice_bot.play_file("#{dir}/#{title}.ogg")
    end

    voice_bot.destroy
    nil    
  end

  command :yt_stop do |event|
    voice = event.bot.voice(event.server)
    
    return 'Nothing is playing' unless voice
    
    voice.stop_playing
    voice.destroy
    
    nil
  end
end