LetterCarrier for PHP Event Bus Using RabbitMQ

letter-carrier.php

<?php 

class LetterCarrier extends AbstractCarrier {

    public function __construct($queueName = , $host = 'localhost', $port = 5672, $username = 'guest', $password = 'guest') {
        parent::__construct($queueName, $host, $port, $username, $password);
    }

    protected function receivedParcel($msg) {
        /* @param AMQPMessage $msg */

        /* get the parcel by unserializing the meesage body */
        $parcel = unserialize($msg->body);

        /* check that the parcel is a Slack carrot */
        if ($parcel instanceof Letter) {
            /* @var $parcel \Franklin\Parcels\LetterParcel */   
            /* do stuff with parcel */
            echo "The message in the letter is: {$parcel->getMessage()}";
        }else{
            echo 'The parcel is not a Letter. Unsure how to handle.';
        }

        // Acknowledge the message so that it's removed from the queue
        $msg->delivery_info['channel']->basic_ack($msg->delivery_info['delivery_tag']);

    }
}