.htaccess

Header add Access-Control-Allow-Origin "*"
Header add Access-Control-Allow-Headers "origin, x-requested-with, content-type"
Header add Access-Control-Allow-Methods "GET, POST, OPTIONS"

db_install.sql

CREATE DATABASE logger;
USE logger;

DROP TABLE IF EXISTS `pixel`;
CREATE TABLE `pixel` (
    `id`                 bigint(20)   NOT NULL AUTO_INCREMENT,
    `impression`         varchar(127) DEFAULT NULL,
    `product`            varchar(80)  DEFAULT NULL,
    `seen`               bigint(100),
    `capt`               bigint(100),
    PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 ;

index.php

<?php header('Access-Control-Allow-Origin: *');
      require '../src/Database/Logger.php';

$filter = array_filter(filter_input_array(INPUT_POST, [
    'impr' => FILTER_VALIDATE_INT,
    'cell' => FILTER_VALIDATE_INT,
    'verb' => FILTER_SANITIZE_STRING,
    'time' => FILTER_VALIDATE_INT,
]));

if (isset($filter['impr'], $filter['time'], $filter['verb']))
{
    $log = New \Database\Logger();
    $row = $log->register($filter);

        die ($row);
}

if (isset($filter['cell'], $filter['time']))
{
    $log = New \Database\Logger();
    $log->update($filter);

        die (418);
}

header("HTTP/1.0 404 Not Found");
die;

JS Tracker

<script src='//code.jquery.com/jquery-latest.min.js'
        type='text/javascript'></script>

<script type='text/javascript'>
    $(function () // do work
    {
        var srv = '//54.201.115.206', // EC2
            blk = 'javascript',
            qst = 'ref';

        var ck = function (name) { var re = new RegExp(name + "=([^;]+)"); var value = re.exec(document.cookie); return (value != null) ? unescape(value[1]) : null; }
        var bu = function (base, key, value){return base + ((base.indexOf('?') > -1) ? '&' : '?') + key + '=' + value;};
        var qs = function (key)
        {
            var match = location.search.match(new RegExp("[?&]" + key.replace(/[*+?^$.\[\]{}()|\\\/]/g, '\\$&') + '=([^&]+)(&|$)'));
            return match && decodeURIComponent(match[1].replace(/\+/g, " "));
        };

        var cat = [
            '70177',  // Medium Duffle Bag  - Heavy Tin
            '70163',  // Original Briefcase - Heavy Tin
            '10519',  // Explorer Jacket - Cover Cloth
            '50125',  // Filson PH Boot
            '63208'   // 1st Avenue Belt
        ];

        var num = location.pathname.split('/').reverse() [0].split('.').reverse() [1],
            itm = location.pathname.split('/').reverse() [0].split('.').reverse() [2],
            lim = Math.round((new Date()).getTime() / 1000) - ck("__utma").split('.').reverse() [1];

        if ('uncrate' === qs(qst))
        {
            if ('-1015' === location.pathname.split('/').reverse() [1]) // strpos for black collection
            {
                $('#subcontent a').each(function ()
                {
                    if(! $(this).attr('href').match(new RegExp(blk, 'gi'))   // not a js link
                    && ! $(this).attr('href').match(new RegExp(qst, 'gi')))  // or has already been applied
                    {
                        $(this).attr('href', bu($(this).attr('href'), qst, 'uncrate')); // bound
                    };
                });
            }
            else if (num.match(new RegExp('^[0-9]{5}$', 'g')) || (lim <= 20 && (-1 !== $.inArray(num, cat)))) // is proid
            {
                $.post(srv, {impr: num, verb: itm, time: Math.round((new Date()).getTime() / 1000)})
                 .done(function (cell)
                 {
                    $('#prodaddbtn').click(function () // rebind
                    {
                        $.post(srv, {cell: cell, time: Math.round((new Date()).getTime() / 1000)});
                    });
                });
            };
        };
    });
</script>

Logger.php

<?php

Namespace Database
{
    Class Logger
    {
        private     $user = false,
                    $pass = false;

        protected   $conn = false;

        public function __construct ()
        {
            $this->user = getenv('DBUSER');
            $this->pass = getenv('DBPASS');

            try {
                $conn = new \PDO('mysql:host=localhost;dbname=logger', $this->user, $this->pass);
                $conn->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
            } catch(\PDOException $e) {
                echo 'ERROR: ' . $e->getMessage();
            }

            $this->conn = $conn;
        }

        public function register ($filter)
        {
            $dbh = $this->conn;

            $stmt = $dbh->prepare(
                'INSERT INTO pixel SET impression = :impr, product = :verb, seen = :time'
            );
                $stmt->execute([
                    ':impr' => $filter['impr'],
                    ':verb' => $filter['verb'],
                    ':time' => $filter['time'],
                ]);

            return $dbh->lastInsertId();
        }

        public function update ($filter)
        {
            $dbh = $this->conn;

            $stmt = $dbh->prepare(
                'UPDATE pixel SET capt = :time WHERE id = :cell'
            );

                $stmt->execute([
                    ':time' => $filter['time'],
                ]);

            return true;
        }
    }
}