Simple Perl script that adds colors to e.g. log files using ANSI escape codes

colorize.pl

#!/usr/bin/env perl

=head1 NAME

colorize.pl -  adds colors to e.g. log files using ANSI escape codes

=head1 SYNOPSIS

    colorize.pl LOGFILE
    some_command | colorize.pl

Some examples:

    $ colorize.pl /var/log/apache/request.log

    $ tail -f /var/log/apache/request.log | colorize.pl

=head1 DESCRIPTION

The colorize.pl script will add colors to a file or stdin. The rules
for adding colors are based on some simple keywords appearing on a
line, e.g. a line containing the string "ERROR" will be red.

=for text
=encoding utf-8
=end

=head1 AUTHOR

Søren Lund, C<< <soren at lund dot org> >>

=head1 SEE ALSO

L<https://en.wikipedia.org/wiki/ANSI_escape_code>

=head1 COPYRIGHT

This file is made available under the Creative Commons CC0 1.0
Universal Public Domain Dedication.

See L<https://creativecommons.org/publicdomain/zero/1.0/deed.en>

=cut

use warnings;
use strict;
use utf8;

$|=1; # no buffering

while(<>) {
	if (/SUCCESS/) {
		print "$_";
	} elsif (/\d+ errors?|ERROR|FATAL|FAILURE/) {
		print "$_";
	} elsif (/WARN|SKIPPED/) {
		print "$_";
	} elsif (/INFO/) {
		print "$_";
	} elsif (/(?:^Downloading:|Downloaded:|^Loading source files for)/) {
		print "$_";
	} else {
		print $_;
	}
}