Magento – how to add shipping city attribute to the cart rules

Create a product attribute called city that has a plaintext City Name - match on this in an observer for the predispatch event of the Mage_Checkout_OnepageController::saveShippingAction.

class MyCompany_MyModule_Model_Observer {

    public function saveShippingActionPredispatch($observer){

        $billing = $observer->getEvent()->getController()->getRequest()->getPost('billing');

        foreach(Mage::getSingleton('checkout/session')->getQuote()->getAllItems() as $item){
            if(!$billing['city']==$item->getProduct()->getCity()){
                Mage::throwException("You can't buy this product because you're shipping to the wrong place!");
            }
        }
    }

}

However, this is the easiest part - the reason Zones Manager is so complex is because this is a very complex problem. Thinking through this - there are many considerations:

• How to handle misspelled city names? (probably would use Zip/Postcodes, obviously)
• How to obtain /manage a list of postcodes?
• How to query the customer for their ultimate shipping address before displaying products to them? Geolocation?
• How to limit the catalog to only show regional items?
• If you instead use category structure for products / cities, how do you limit them from purchasing a product that wasn't intended for a city at the end of the day?
• Are you concerned about this complexity impacting your conversion rate?

(corrected the code by putting the missing curly bracket to close the foreach loop)

I solved it like that

Just change process function in Validator.php to

public function process($_quote) {
    $i               = 0;
    $quote           = $_quote;
    $customerSession = Mage::getSingleton('customer/session');
    foreach ($this->_rules as $rule) {
        // @var $rule FME_Affiliates_Model_Program
        // already tried to validate and failed
        if ($rule->getIsValid() === false) {
            continue;
        }
        if ($rule->getIsValid() !== true) { 
            $rule->afterLoad();
            if (!$rule->validate($quote)) { // quote does not meet rule's conditions , //Call Found.php
                $rule->setIsValid(false);
                continue;
            }
            $rule->setIsValid(true); // passed all validations, remember to be valid
        }

        $this->_appliedProductsIds[]                 =  Mage::getSingleton('checkout/session')->getReturnProductRuleValues();
        $this->_appliedProductsIds[$i]['program_id'] =  $rule->getProgramId();
        Mage::getSingleton('checkout/session')->unsReturnProductRuleValues($this->_ReturnValues);
        $i = $i + 1;
    }
    return $this;
}

And validate function in Found.php to

public function validate(Varien_Object $object) { 
//Called form Validator.php
    $all       = $this->getAggregator() === 'all';
    $true      = (bool)$this->getValue();
    $found     = false;

$Count =  count($object->getAllItems()); 
$i = 0;
    foreach ($object->getAllItems() as $item) {
        $found = $all ? true : false;
        foreach ($this->getConditions() as $cond) {

            $validated = $cond->validate($item); // Call to Product.php's function 'validate'

    if($validated) {
        $this->_ProductId[] = $item->getProductId();
    }

    if($i == $Count) {
        if ($all && !$validated) {
        $found = false;
        break;
        } elseif (!$all && $validated) {
        $found = true;
        break 2;
        }
    }

        }
    if($i == $Count) {
    if ($found && $true) {
        break;
    }
    }
    $i = $i + 1;
    }

$this->_ReturnValues['Product_Id'] = $this->_ProductId;
if(!empty($this->_ProductId)) {
    $this->_ReturnValues['Bool'] = true;
} else {
    $this->_ReturnValues['Bool'] = false;
}

    if ($found && $true) {
        // found an item and we're looking for existing one
    Mage::getSingleton('checkout/session')->setReturnProductRuleValues($this->_ReturnValues);
        return true;
    } elseif (!$found && !$true) {
        // not found and we're making sure it doesn't exist
    Mage::getSingleton('checkout/session')->setReturnProductRuleValues($this->_ReturnValues);
        return true;
    }
Mage::getSingleton('checkout/session')->setReturnProductRuleValues($this->_ReturnValues);
    return false;
}

And access the values in Observer with Vadidator class object like $appliedProductsIds = $validator->_appliedProductsIds;

Hop this will help someone..