发送股票更新电子邮件Magento

我一直在为我的Magento商店开发这个股票更新电子邮件警报模块，我的代码基于这里的一个Magento堆栈交换线程。经过多次摆弄，我终于有了自己的版本。我想知道为什么示例代码不起作用：

class MyCompany_MyModule_Model_Observer
{
    public function lowStockReport($observer)
    {
        $stockItem = $observer->getEvent();
        if($stockItem->getQty() < $stockItem->getNotifyStockQty()){
            //stock is lower than the notify amount, send email
            $product = Mage::getModel('catalog/product')->load($stockItem->getProductId());
            $body = "{$product->getName()} :: {$product->getSku()} just Ran out of stock:'n'n";
            $body .= "Current Qty: {$stockItem->getQty()}'n";
            $body .= "Low Stock Date: {$stockItem->getLowStockDate()}'n";
            $mail = new Zend_Mail();
            $mail->setType(Zend_Mime::MULTIPART_RELATED);
            $mail->setBodyHtml($body);
            $mail->setFrom('lowstock@yourwebsite.com', 'Low Stock Notifier');
            $mail->addTo('youremail@gmail.com', 'Your Name Here');
            $mail->setSubject('[Notice] An Item Has Gone Out of Stock');
            $mail->send();
        }
    }
} 

然而，我的脏代码确实运行得很好：

class Custom_Stockupdate_Model_Observer
{
    public function lowStockReport($observer)
    {
        $stockItem = $observer->getEvent();
        $myItem = ($stockItem->debug());
        $theQty = $myItem['data_object (Mage_CatalogInventory_Model_Stock_Item)']['qty'];
        $theId = $myItem['data_object (Mage_CatalogInventory_Model_Stock_Item)']['product_id'];
        if($theQty == '0'){
            //stock is lower than the notify amount, send email
            $product = Mage::getModel('catalog/product')->load($theId);
            $body = "{$product->getName()} :: {$product->getSku()} just Ran out of stock:'n'n";
            $body .= "Current Qty: {$theQty}'n";
            $mail = new Zend_Mail();
            $mail->setType(Zend_Mime::MULTIPART_RELATED);
            $mail->setBodyHtml($body);
            $mail->setFrom('lowstock@yourwebsite.com', 'Low Stock Notifier');
            $mail->addTo('youremail@gmail.com', 'Your Name Here');
            $mail->setSubject('[Notice] An Item Has Gone Out of Stock');
            $mail->send();
        }
    }
} 

任何我错过的批评和最佳实践都将不胜感激，因为我还是一个新手。