Magento - Issue with creating a custom Module - php

Question

I'm using Magento 1.9.1 and i'm trying to create a module which is giving a 50% discount from the grand total.
Here is my code:
/app/code/local/VivasIndustries/PercentPayment/etc/config.xml :
<?xml version="1.0"?>
<config>
<modules>
<VivasIndustries_PercentPayment>
<version>0.1.0</version>
</VivasIndustries_PercentPayment>
</modules>
<global>
<sales>
<quote>
<totals>
<discount>
<class>VivasIndustries_PercentPayment_Model_Discount</class>
<after>subtotal</after>
</discount>
</totals>
</quote>
<order_invoice>
<totals>
<discount>
<class>VivasIndustries_PercentPayment_Model_Invoice</class>
<after>subtotal</after>
</discount>
</totals>
</order_invoice>
<order_creditmemo>
<totals>
<discount>
<class>VivasIndustries_PercentPayment_Model_Creditmemo</class>
<after>subtotal</after>
</discount>
</totals>
</order_creditmemo>
</sales>
</global>
</config>
/app/code/local/VivasIndustries/PercentPayment/controllers/IndexController.php :
<?PHP
class VivasIndustries_PercentPayment_Model_Discount extends Mage_Sales_Model_Quote_Address_Total_Abstract {
public function collect(Mage_Sales_Model_Quote_Address $address) {
if ($address->getData('address_type') == 'billing')
return $this;
$discount = 50; //your discount percent
$grandTotal = $address->getGrandTotal();
$baseGrandTotal = $address->getBaseGrandTotal();
$totals = array_sum($address->getAllTotalAmounts());
$baseTotals = array_sum($address->getAllBaseTotalAmounts());
$address->setFeeAmount(-$totals * $discount / 100);
$address->setBaseFeeAmount(-$baseTotals * $discount / 100);
$address->setGrandTotal($grandTotal + $address->getFeeAmount());
$address->setBaseGrandTotal($baseGrandTotal + $address->getBaseFeeAmount());
return $this;
}
public function fetch(Mage_Sales_Model_Quote_Address $address) {
if ($address->getData('address_type') == 'billing')
return $this;
$amt = $address->getDiscountAmount();
if ($amt != 0) {
$address->addTotal(array(
'code' => 'Discount',
'title' => 'Discount',
'value' => $amt
));
}
return $address;
}
}
?>
/app/etc/modules/VivasIndustries_PercentPayment.xml :
<?xml version="1.0"?>
<config>
<modules>
<VivasIndustries_PercentPayment>
<active>true</active>
<codePool>local</codePool>
</VivasIndustries_PercentPayment>
</modules>
</config>
This are all files which i've created for my new module. All what i've done.
I was using this guide: http://magento.ikantam.com/qa/how-add-discount-total-magento
Now when i try to open my checkout page i got error - There has been an error processing your request
When i open my error_log i can see this thing:
[09-Nov-2014 18:22:35 UTC] CSRF state token does not match one provided.
Can you please help me fix this problem and make my new Module works like intended ?
Thanks in advance!

Answer 1

Modifying total is always difficult part. And it's hard find out the problem in your code unless I have set up of that module in my system. Anyway here I have shared some codes for modifying total during checkout process. I explained as much I can.
For this you have to update lot of things. Quote, Address, Order, Creditmemo , Invoice, shipping, multi shipping etc. Okay here we go,
First we need to create our configuration file that's called config.xml,
config.xml
Update:
<config>
<modules>
<VivasIndustries_PercentPayment>
<version>0.1.0</version>
</VivasIndustries_PercentPayment>
</modules>
<global>
<helpers>
<percentpayment>
<class>VivasIndustries_PercentPayment_Helper</class>
</percentpayment>
</helpers>
<models>
<percentpayment>
<class>VivasIndustries_PercentPayment_Model</class>
<resourceModel>percentpayment_mysql4</resourceModel>
</percentpayment>
</models>
<resources>
<salesattribute1416562342_setup>
<setup>
<module>VivasIndustries_PercentPayment</module>
<class>Mage_Sales_Model_Mysql4_Setup</class>
</setup>
<connection>
<use>core_setup</use>
</connection>
</salesattribute1416562342_setup>
<salesattribute1416562342_write>
<connection>
<use>core_write</use>
</connection>
</salesattribute1416562342_write>
<salesattribute1416562342_read>
<connection>
<use>core_read</use>
</connection>
</salesattribute1416562342_read>
</resources>
<events>
<checkout_type_onepage_save_order_after> <!-- identifier of the event we want to catch -->
<observers>
<checkout_type_onepage_save_order_after_discount_handler> <!-- identifier of the event handler -->
<type>model</type> <!-- class method call type; valid are model, object and singleton -->
<class>percentpayment/newordertotalobserver</class> <!-- observers class alias -->
<method>saveDiscountTotal</method> <!-- observer's method to be called -->
<args></args> <!-- additional arguments passed to observer -->
</checkout_type_onepage_save_order_after_discount_handler>
</observers>
</checkout_type_onepage_save_order_after>
<checkout_type_multishipping_create_orders_single> <!-- identifier of the event we want to catch -->
<observers>
<checkout_type_multishipping_create_orders_single_discount_handler> <!-- identifier of the event handler -->
<type>model</type> <!-- class method call type; valid are model, object and singleton -->
<class>percentpayment/newordertotalobserver</class> <!-- observers class alias -->
<method>saveDiscountTotalForMultishipping</method> <!-- observer's method to be called -->
<args></args> <!-- additional arguments passed to observer -->
</checkout_type_multishipping_create_orders_single_discount_handler>
</observers>
</checkout_type_multishipping_create_orders_single>
</events>
<sales>
<quote>
<totals>
<discount_total>
<class>percentpayment/quote_address_total_discount</class>
<after>subtotal,freeshipping,tax_subtotal,shipping</after>
<before>grand_total</before>
</discount_total>
</totals>
</quote>
<order_invoice>
<totals>
<discount_total>
<class>percentpayment/order_invoice_total_discount</class>
<after>subtotal,freeshipping,tax_subtotal,shipping</after>
<before>grand_total</before>
</discount_total>
</totals>
</order_invoice>
<order_creditmemo>
<totals>
<discount_total>
<class>percentpayment/order_creditmemo_total_discount</class>
<after>subtotal,freeshipping,tax_subtotal,shipping</after>
<before>grand_total</before>
</discount_total>
</totals>
</order_creditmemo>
</sales>
</global>
</config>
change other things as per this configuration. before that go to your database using phpmyadmin open core_resources table. and delete your module entry if it is there. that's it.
Please comment here, if you have any doubt.