Testing some ways to generate short GUID

01-guid_collision.pl

#!/usr/bin/env perl

use strict;
use warnings;

use Data::GUID;
use Digest::CRC 'crc32';
use Data::Printer;

my %keys_hex;
my %keys_b64;

my $sample = shift(@ARGV) || 1_000_000;

for (my $cpt = 0 ; $cpt < $sample ; $cpt++) {
  my $guid = Data::GUID->new();
  my $crc_hex  = crc32( $guid->as_hex() );
  my $crc_b64  = crc32( $guid->as_base64() );
  push @{$keys_hex{$crc_hex}}, $guid->as_string();
  push @{$keys_b64{$crc_b64}}, $guid->as_string();
}

my $b64_collisions = 0;
map { $b64_collisions++ if scalar( @{$keys_b64{$_}} ) > 1 } keys %keys_b64;

my $hex_collisions = 0;
map { $hex_collisions++ if scalar( @{$keys_hex{$_}} ) > 1 } keys %keys_hex;

print "We have $b64_collisions collisions for the Base64 version.\n";
print "We have $hex_collisions collisions for the Hex version.\n";