cpanfile

requires 'IO::Uncompress::RawInflate';
requires 'XML::Twig';
requires 'Mojolicious';
#!/usr/bin/env perl
use v5.24;
use warnings;
use experimental 'signatures';
no warnings 'experimental::signatures';

use FindBin '$Bin';
use lib "$Bin/local/lib/perl5";

use MIME::Base64;
use IO::Uncompress::RawInflate;
use Mojo::URL;
use XML::Twig;

my $url = shift // die "$0 <url>\n";
my $sreq = get_urlparam($url, 'SAMLRequest');
say "\nSAMLRequest = $sreq\n";
my $xml = decode_saml($sreq);
say pretty_xml($xml);

sub decode_saml ($input) {
   my $binary = MIME::Base64::decode_base64($input);
   my $output;
   IO::Uncompress::RawInflate::rawinflate(\$binary, \$output);
   return $output;
}

sub get_urlparam ($url, $name) { Mojo::URL->new($url)->query->param($name) }

sub pretty_xml ($input) {
   XML::Twig->new(pretty_print => 'indented')->parse($input)->sprint
}