How to get Diamond Inventory from RapNet using API ?

<?php
$data = '{"request": {"header": {"username": "xxxxxxx","password": "xxxx"},
"body": {
"shapes": [],
"size_to": "",
"size_from": "",
"color_from": "",
"color_to": "",
"clarity_from": "",
"clarity_to": "",
"cut_from": "",
"cut_to": "",
"polish_from": "",
"polish_to": "",
"symmetry_from": "",
"symmetry_to": "",
"labs": [],
"price_total_from": "",
"price_total_to": "",
"page_number": "1",
"page_size": "20",
"sort_by": "price",
"sort_direction": "ASC"
}}}';
$curl = curl_init();
curl_setopt($curl, CURLOPT_POST, 1);
curl_setopt($curl, CURLOPT_POSTFIELDS, $data);

curl_setopt($curl, CURLOPT_URL, 'http://technet.rapaport.com/HTTP/JSON/RetailFeed/GetDiamonds.aspx');
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
$result = curl_exec($curl);
$data = json_decode($result,true);
$diamonds_returned = $data['response']['body']['search_results']['diamonds_returned'];
$total_diamonds_found =  $data['response']['body']['search_results']['total_diamonds_found'];
echo "<pre>";
print_r($data);
curl_close($curl);
?>

How to Change the price before adding to cart in magento with custom option selection price?

Put below code in app\code\community\YBizz\PriceChange\Model\Observer.php

<?php
class DRC_PriceChange_Model_Observer  {

    public function change_price(Varient_Event_Observer $observer) 
    {   
        $item = $observer->getQuoteItem();
        if ($item->getParentItem()) {$item = $item->getParentItem();}
        $price = $item->getProduct()->getFinalPrice();
        $new_price = 20 + $price;

        $item->setCustomPrice($new_price);
        $item->setOriginalCustomPrice($new_price);
        $item->getProduct()->setIsSuperMode(true);      
    }
}
?>

How to get value of Attribute Option in magento ?

<?php
require_once '../app/Mage.php';
umask(0) ;
Mage::app();

function getAttributeOptionValue($arg_attribute, $arg_value)
{
$attribute_model = Mage::getModel('eav/entity_attribute');
$attribute_options_model= Mage::getModel('eav/entity_attribute_source_table');  
$attribute_code = $attribute_model->getIdByCode('catalog_product', $arg_attribute);
$attribute = $attribute_model->load($attribute_code);
$attribute_table = $attribute_options_model->setAttribute($attribute);
$options = $attribute_options_model->getAllOptions(false);  
foreach($options as $option)
{
if ($option['label'] == $arg_value)
{
return $option['value'];
}
}  
return false;
}
echo $optionValue = getAttributeOptionValue("diamond_symmetry", "Very Good");
?>

How to add new value in attribute magento ?

<?php
require_once 'app/Mage.php';
umask(0) ;
Mage::app();

$optionValue = addAttributeValue("diamond_symmetry", "Excellent");

function addAttributeValue($arg_attribute, $arg_value)
    {
        $attribute_model        = Mage::getModel('eav/entity_attribute');

        $attribute_code         = $attribute_model->getIdByCode('catalog_product', $arg_attribute);
        $attribute              = $attribute_model->load($attribute_code);

        if(!attributeValueExists($arg_attribute, $arg_value))
        {
            $value['option'] = array($arg_value,$arg_value);
            $result = array('value' => $value);
            $attribute->setData('option',$result);
            $attribute->save();
        }

$attribute_options_model= Mage::getModel('eav/entity_attribute_source_table') ;
        $attribute_table        = $attribute_options_model->setAttribute($attribute);
        $options                = $attribute_options_model->getAllOptions(false);

        foreach($options as $option)
        {
            if ($option['label'] == $arg_value)
            {
                return $option['value'];
            }
        }
       return false;
    }

function attributeValueExists($arg_attribute, $arg_value)
    {
        $attribute_model        = Mage::getModel('eav/entity_attribute');
        $attribute_options_model= Mage::getModel('eav/entity_attribute_source_table') ;

        $attribute_code         = $attribute_model->getIdByCode('catalog_product', $arg_attribute);
        $attribute              = $attribute_model->load($attribute_code);

        $attribute_table        = $attribute_options_model->setAttribute($attribute);
        $options                = $attribute_options_model->getAllOptions(false);

        foreach($options as $option)
        {
            if ($option['label'] == $arg_value)
            {
                return $option['value'];
            }
        }

        return false;
    }
?>