Magento adding downloadable product to cart by coding php

Probably you know it’s possible to add a product to the cart via querystring, but may be you prefer code a new module for your needs using Magento objects and methods.

So adding a simple product is easy:

...

$cart = Mage::getSingleton('checkout/cart');

// start adding the product

try {

$cart->addProduct($product, array('qty' => 1));

// save the cart

$cart->save();

$result = null;

} catch (Mage_Core_Exception $e) {

$result = $e->getMessage();

}

But how to add a Downloadable product with its right link? Just try this, it’s a controller I used to integrate an “add to cart” API:

public function cartaddAction()
{
$productId  = (int) $this->getRequest()->getParam('id');
$callback  = (string) $this->getRequest()->getParam('callback');

$cart = Mage::getSingleton('checkout/cart');

// call the Magento catalog/product model
$product = Mage::getModel('catalog/product')
// set the current store ID
->setStoreId(Mage::app()->getStore()->getId())
// load the product object
->load($productId);

$links = Mage::getModel('downloadable/product_type')->getLinks( $product );

foreach ( $links as $link )
if ( preg_match("/epub/i", $link->getTitle()) )
$linkId = $link->getLinkId();

// Here is the trick to add the right link id

$input = array( 'qty' => 1, 'links' => array( $linkId ) );
$request = new Varien_Object();
$request->setData($input);

// start adding the product
try {
$cart->addProduct($product, $request);
// save the cart
$cart->save();

$result = null;
} catch (Mage_Core_Exception $e) {
$result = $e->getMessage();
}

// very straightforward, set the cart as updated
Mage::getSingleton('checkout/session')->setCartWasUpdated(true);
}