Basket Sales Row Totals

Sales Row Totals are defined in config.xml in the nodes:

<sales>
    <quote>
        <totals>
            <shipping>
                <class>sales/quote_address_total_shipping</class>
                <after>subtotal,freeshipping,tax_subtotal</after>
                <before>grand_total</before>
            </shipping>
        </totals>
    </quote>
</sales>

The class node is instantiated by each total type, and then collect is called on each. The fetch method actually adds the total type to the address — up until this point the config.xml definition only declares the total types which should be queried for addition. Logic could exist in the fetch method to check whether the total type should be added at all. Additionally, the fetch method could add more than one type of total, as the Mage_Tax_Model_Sales_Total_Quote_Tax does.

<?php
  public function fetch(Mage_Sales_Model_Quote_Address $address)
    {
        $amount = $address->getShippingAmount();
       if ($amount != 0 || $address->getShippingDescription()) {
            $title = Mage::helper('sales')->__('Shipping & Handling');
            if ($address->getShippingDescription()) {
                $title .= ' (' . $address->getShippingDescription() . ')';
            }
            $address->addTotal(array(
                'code' => $this->getCode(),
                'title' => $title,
                'value' => $address->getShippingAmount()
            ));
        }
        return $this;
    }

These are rendered by the Mage_Checkout_Block_Cart_Totals‘ renderTotal method. A total can also have a block total renderer assigned to it instead of having to rely on the default output in the cart rows. The block is instantiated using the node names of the total config definition. The total node name is used (in the node) with _total_renderer appended to it. This is done in the Cart Totals’ _getTotalRenderer() method. In the example above, the renderer would be called *shipping_total_renderer*.

Fishpigs Total Renderer Example

Fish pigs add a cart total renderer to the cart. To achieve this, they add a shipping_total_renderer in their layout XML:

<layout>
	
	<checkout_cart_index>
		<reference name="checkout.cart.totals">
			<block type="basketshipping/total_shipping" name="shipping_total_renderer" />
		</reference>
	</checkout_cart_index>
	
</layout>

– This block will now be rendered for the shipping_total. Due to the way the fetch method works however, the row will only be added to the cart totals is not equal to zero or the address does not has a shipping description. This can be changed by overwriting the Mage_Sales_Model_Quote_Address_Total_Shipping model.

Notes on Magento’s Tax Module

Magento’s tax modules adds renderers to many of the sales/quote/total rows. This may often be overlooked when looking at the config file from Magento’s Sales module. This changes the renderers of the subtotal, shipping, discount, and grand total to renderer blocks within the tax module:

 <subtotal>
    <renderer>tax/checkout_subtotal</renderer>
    <admin_renderer>adminhtml/sales_order_create_totals_subtotal</admin_renderer>
</subtotal>
<shipping>
    <renderer>tax/checkout_shipping</renderer>
    <admin_renderer>adminhtml/sales_order_create_totals_shipping</admin_renderer>
</shipping>
<discount>
    <renderer>tax/checkout_discount</renderer>
    <admin_renderer>adminhtml/sales_order_create_totals_discount</admin_renderer>
</discount>
<grand_total>
    <renderer>tax/checkout_grandtotal</renderer>
    <admin_renderer>adminhtml/sales_order_create_totals_grandtotal</admin_renderer>
</grand_total>

Basket Row Total Areas

There are three main areas in the shipping row totals: footer, taxes, and null. Null is the default area any is output by default, other renderers require explicit output in a template, such as the taxes area. This area area is only created if tax/cart_display/grandtotal is set to Yes.

The position of taxes in Magento will render based on the tax/cart_display/grandtotal setting. If this setting is set to Yes, then the tax will not be output as part of the regular totals, and assigned to the taxes area, which by default is output as part of the grand total template (tax/checkout/grandtotal.phtml):

<?php echo $this->renderTotals('taxes', $this->getColspan()); ?>

The area is set in the fetch method of Mage_Tax_Model_Sales_Total_Quote_Tax:

$area = null;
if ($this->_config->displayCartTaxWithGrandTotal($store) && $address->getGrandTotal()) {
    $area = 'taxes';
}

if (($amount != 0) || ($this->_config->displayCartZeroTax($store))) {
    $address->addTotal(array(
        'code' => $this->getCode(),
        'title' => Mage::helper('tax')->__('Tax'),
        'full_info' => $applied ? $applied : array(),
        'value' => $amount,
        'area' => $area
    ));
}

If the tax/cart_display/grandtotal is set to “No”, then area doesn’t get assigned, and defaults to null, so the total will be output alongside all of the other totals.