Back Orders

Product Back Orders 

This feature allows the Admin to decide if their website will allow negative orders. Once enabled and integrated into orders, the website will allow the checkout for any products who have quantity of zero or less. 

To allow Back Orders for all products, navigate to Catalogues module → Configure → Manage Configuration and click the "Allow Back Orders" switch.

In prodcatalogue templates, this value will be available as $allow_back_orders

<{$allow_back_orders}>

Suggestion of implementation:

<{if !$allow_back_orders && $product->getQty() <= 0}>
    // deny add to cart view partial
<{else}>
    <{if $product->getQty() <= 0 && $product->getRestockDate('U') > $smarty.now}>
        // Show message about when product will be back in stock
    <{/if}>
    // allow add to cart view partial
<{/if}>

On checkout with Back Orders enabled and when a Product has hit quantity zero, the site admin will receive a mail notifying them that the stock for this product is zero. 

Back orders is not compatible with the 'stock-active' centre option. If you are receiving the error "<product name> is out of stock" you must remove the 'stock-active' centre option.