script for cross check of iptables and container inspect

test_docker_port.pl

use strict;
use warnings;

use JSON qw(decode_json);

my %iptables;
foreach my $iptables_row (qx(iptables -L -n -t nat | grep DNAT)) {
        if ($iptables_row =~ /dpt:(\d+)\s+to:([\d\.]+)/) {
                my $port = $1;
                my $ip = $2;

                $iptables{$ip}{$port} = 0;
        }
}

my @dockers_id = qx(docker ps --format={{.ID}});

foreach my $docker_id (@dockers_id) {
        chomp $docker_id;

        print "inspect $docker_id\n";
        my $inspect = qx(docker inspect $docker_id);
        my $docker_inspect = decode_json($inspect);

        my $ip_adress = $docker_inspect->[0]->{NetworkSettings}->{IPAddress};

        my @ports;
        foreach my $from_port (keys %{$docker_inspect->[0]->{NetworkSettings}->{Ports}}) {
                my $ports = $docker_inspect->[0]{NetworkSettings}{Ports}{$from_port};

                foreach my $port (@$ports) {
                        push @ports, $port->{HostPort};
                }

        }

        if (!@ports) {
                print "No exposed port\n";
        }
        elsif (!exists $iptables{$ip_adress}) {
                print "Should be exists ip $ip_adress\n";
        }
        elsif (scalar keys $iptables{$ip_adress} != scalar @ports) {
                print "Wired\n";
                print Dumper $iptables{$ip_adress};
                print Dumper \@ports;
        }
}