Concept code for AnyEvent::RabbitMQ

I need some advice for this concept.

use AnyEvent::RabbitMQ;

my $cv = AnyEvent->condvar;

my $failur_cb = sub {
    warn @_;
    $cv->send;
};

my $ar = AnyEvent::RabbitMQ->new({
    timeout => 1,
})->load_xml_spec(
    '/path/to/amqp0-8.xml',
)->connect({
    host           => 'localhosti',
    port           => 5672,
    user           => 'guest',
    port           => 'guest',
    vhost         => '/',
    on_success => sub {
        $ar->open_channel({
            channel_id => 1,
            on_success => sub {
                my $channel = shift;
                $channel->declare_exchange({
                    exchange   => 'test_exchange',
                    on_success => sub {
                        print 'Declared exchange', "\n";
                        $cv->send;
                    },
                    on_failur  => $failur_cb,
                });
            },
            on_failur  => $failur_cb,
        });
    },
    on_failur  => $failur_cb,
});

$cv->recv;