Gets youtube video URL and exports mp3 file while asking for artist and title

Usage

~/Dev/ytdl ❯ ruby ytdl.rb https://www.youtube.com/watch\?v\=ftIBZNklEFU                                                                                                                            R: 2.2.2
[youtube] ftIBZNklEFU: Downloading webpage
[youtube] ftIBZNklEFU: Downloading video info webpage
[youtube] ftIBZNklEFU: Extracting video information
[youtube] ftIBZNklEFU: Downloading DASH manifest
[youtube] ftIBZNklEFU: Downloading DASH manifest
[download] Destination: Acid Interstate V1 - 2015 Remake-ftIBZNklEFU.m4a
[download] 100% of 3.33MiB in 00:01
[ffmpeg] Correcting container in "Acid Interstate V1 - 2015 Remake-ftIBZNklEFU.m4a"
[ffmpeg] Destination: Acid Interstate V1 - 2015 Remake-ftIBZNklEFU.mp3
Deleting original file Acid Interstate V1 - 2015 Remake-ftIBZNklEFU.m4a (pass -k to keep)

File name: Acid Interstate V1 - 2015 Remake-ftIBZNklEFU.mp3
Artist: No idea
Title: Acid Interstate

Enjoy!
~/Dev/ytdl ❯

ytdl.rb

#!/usr/bin/env ruby
# Requires youtube-dl (https://rg3.github.io/youtube-dl/),
# ffmpeg (https://www.ffmpeg.org/download.html)
# and https://github.com/moumar/ruby-mp3info (gem install ruby-mp3info)

require "mp3info" # imports required library for use

url = ARGV.shift # ARGV is an array of arguments passed to the script
command = "youtube-dl -x --audio-format mp3 --audio-quality 0 #{ url }"
file_name = nil
IO.popen(command) do |io| # runs a command and exposes stream of it's output
  while (line = io.gets) do
    puts line
    if match = line.match(/\[ffmpeg\] Destination: (.+)/) # Checks for line that starts with '[ffmpeg] Destination: ' and extracts the rest of it
      file_name ||= match[1] # here we actually get the first something in parentheses from line above
    end
  end
end

puts
puts "File name: %s" % file_name

Mp3Info.open(file_name) do |mp3| # that's just mp3info usage (https://github.com/moumar/ruby-mp3info)
  print "Artist: "
  mp3.tag.artist = gets.chomp
  print "Title: "
  mp3.tag.title = gets.chomp
end

puts
puts "Enjoy!"