update_ics_uids.pl

#!/usr/bin/perl

#
# Updates UID's listed in an .ics file
#
# Written to address the problem of importing calendar entries from an .ics
# into a Google Calendar, deleting them all, then finding that Google Calendar
# will not allow reimporting entries that it's already seen.
#
# This program updates the .ics in place, so make a backup copy first.
#
# Invocation:
#
# $ ./update_ics_uids.pl /tmp/your_entries.ics
#

use perl5i::2;
use IO::All;
use Data::UUID;

func main {
	die "Must specify a filename to modify in place." unless
		$ARGV[0];
	my $ical = io $ARGV[0];

	my $ug = Data::UUID->new();

	for (my $i = 0; $i < $#$ical; $i++) {
		if ($ical->[$i] =~ m/^UID:/) {
			$ical->[$i] = 'UID:' . $ug->create_str() . "\n";
		}
	}
}

main() if $0 eq __FILE__;