Batch-download YouTube videos to MP3s with ID3 Tags

W-V2Cm8CLJ4|Tony D'Aloia|Napoli

tfsisahydZw|Antonella|Arrivera' L'Estate

Am-HUOiRWXo|Antonella|La Mia Poesia

apt-get install youtube-dl

apt-get install id3tool

# Use strict!
use strict;

# Textfile parameter.
my $textfile = @ARGV[0];

# The "vids" array stores each line of the textfile.
my @vids;

# The "track" array that each line of the textfile is split into.
my @track;

# The variables used for storing information on each YouTube video.
my $id, my $artist, my $title, my $url, my $file, my $i;

# Find paths to required binaries.
chop(my $id3tool = `whereis id3tool | awk '{ print \$2}'`);
chop(my $youtube-dl = `whereis youtube-dl | awk '{ print \$2}'`);
chop(my $flv2mp3 = `whereis flv2mp3 | awk '{ print \$2}'`);

# Print welcome message.
print "youtube-grabber 0.05\n";
print "Written by Derek Pascarella\n\n";

# If one of the required binaries doesn't exist, print an error.
if($id3tool eq "" || $youtube-dl eq "" || $flv2mp3 eq "")
{
    print "Error!\n";
    print "Your system is missing required binaries.\n\n";
    print "id3tool: ";
    
    if($id3tool ne "")
    {
        print "found\n";
    }
    else
    {
        print "missing\n";
    }
    
    print "youtube-dl: ";

    if($youtube-dl ne "")
    {
        print "found\n";
    }
    else
    {
        print "missing\n";
    }


    print "flv2mp3: ";

    if($flv2mp3 ne "")
    {
        print "found\n";
    }
    else
    {
        print "missing\n";
    }
}
# If no textfile was specified, print an error.
elsif($textfile eq "")
{
    print "Error!\n";
    print "Usage: youtube-grabber.pl <textfile>\n";
}
# If a textfile was specified and exists, proceed.
elsif($textfile ne "" && -e $textfile)
{
    # Open textfile containing YouTube video information.
    open(TEXTFILE, "$textfile");
    chop(@vids = <TEXTFILE>);
    close(TEXTFILE);
    
    # Print number of videos found in textfile.
    print $#vids + 1 . " video ID(s) found in \"$textfile\"\n\n";

    # Parse through each line of the textfile.
    for($i = 0; $i <= $#vids; $i ++)
    {
        # Split current line by the pipe character (|).
        @track = split(/\|/, @vids[$i]);
        
        # Parse out the video ID, artist and song title.
        $id = @track[0];
        $artist = @track[1];
        $title = @track[2];
        
        # Create "url" and "file" variables.
        $url = "http://www.youtube.com/watch?v=" . $id;
        $file = $id . ".flv";
    
        # Print the artist and song title for the YouTube video
        # currently being worked on.
        print $i + 1 . ". $artist - $title\n";
        
        # Download FLV file from YouTube.
        print "\nyoutube-dl \"$url\"\n";
        system "$youtube-dl \"$url\"";
        
        # Convert the FLV file to an MP3.
        print "\nflv2mp3 $file \"$artist - $title.mp3\"\n";
        system "$flv2mp3 $file \"$artist - $title.mp3\"";
        
        # Tag the MP3 using the artist and song title information
        # from the textfile.
        print "\nid3tool -r \"$artist\" -t \"$title\" \"$artist - $title.mp3\"\n";
        system "id3tool -r \"$artist\" -t \"$title\" \"$artist - $title.mp3\"";
        
        # Remove the FLV file.
        print "\nCleaning up...\n";
        system "rm $file";
        
        # Sleep 2 seconds before the next download begins, reducing
        # timeouts.
        print "\nSleeping 2 seconds before beginning next download...\n\n";
        system "sleep 2";
    }
    
    print "Process complete!\n\n";
    print "Enjoy :)\n";
}
# If the textfile doesn't exist, print an error.
else
{
    print "Error!\n";
    print "Your textfile \"$textfile\" does not exist!\n";
}