Magento - Create a minimum shipping charge

We use USPS API for international shipping. The API returns a shipping cost and we add % Handling charge. We want to set a minimum charge, e.g., i开发者_如何学Gof shipping + handling is less than $5 we want to set the shipping price to $5. Would this require writing a full shipping module or just adapt the USPS module?

You can accomplish this by overriding just a portion of the USPS module. The method that applies handling is in Mage_Shipping_Model_Carrier_Abstract:

public function getFinalPriceWithHandlingFee($cost) 

To override this method for US, create a new model override on Mage_Usa_Model_Shipping_Carrier_Usps (see elsewhere for how to set up this override):

class Namespace_Module_Model_Shipping_Carrier_Usps extends Mage_Usa_Model_Shipping_Carrier_Usps {

    function getFinalPriceWithHandlingFee($cost) {
        $parentValue = parent::getFinalPriceWithHandlingFee($cost);
        return max($parentValue,5);
    }
}

This will implement a "floor" for shipping prices. Keep in mind that this may in some cases lead to results that users notice as being odd. For contrived example:

• First Class - $5.00
• Media Mail - $5.00
• Priority Mail - $5.33

Keep it aboveboard and let them know that you're doing this.

Hope that helps!

Thanks, Joe