Using Omnipay Paypal With Laravel Controller

PaymentController.php

<?php

use Omnipay\Omnipay;

class PaymentController extends Controller
{
	private $data;

	public function getIndex()
	{	
		$this->data['product'] = 'Aurvana Platinum';
		$this->Data['productImage'] = 'http://img.creative.com/images/products/large/pdt_21734.png.ashx?width=200';
		$this->data['price'] = '299.00';
		$this->data['currency'] = 'USD';
		$this->data['description'] = 'Flagship Over-the-ear Bluetooth® Headset with NFC';
		return View::('hello', $this->data);
	}

	public function postPayment() 
	{
        	$params = array(
              		'cancelUrl' 	=> 'http://localhost/cancel_order',
              		'returnUrl' 	=> 'http://localhost/payment_success', 
                	'name'		=> Input::get('name'),
                	'description' 	=> Input::get('description'), 
                	'amount' 	=> Input::get('price'),
                	'currency' 	=> Input::get('currency')
        	);
            
        	Session::put('params', $params);
        	Session::save();  
	    
	   	$gateway = Omnipay::create('PayPal_Express');
	   	$gateway->setUsername('paypal account');
   		$gateway->setPassword('paypal password');
   		$gateway->setSignature('AiPC9BjkCyDFQXbSkoZcgqH3hpacASJcFfmT46nLMylZ2R-SV95AaVCq');

	   	$gateway->setTestMode(true);

	  	$response = $gateway->purchase($params)->send();

    		if ($response->isSuccessful()) {
	      
	      		// payment was successful: update database
	      		print_r($response);

		} elseif ($response->isRedirect()) {
	      		
	      		// redirect to offsite payment gateway
	      		$response->redirect();

	  	} else {

		      // payment failed: display message to customer
		      echo $response->getMessage();

	  	}
	}
	
	public function getSuccessPayment()
  	{
   		$gateway = Omnipay::create('PayPal_Express');
   		$gateway->setUsername('paypal account');
   		$gateway->setPassword('paypal password');
   		$gateway->setSignature('AiPC9BjkCyDFQXbSkoZcgqH3hpacASJcFfmT46nLMylZ2R-SV95AaVCq');
   		$gateway->setTestMode(true);
      	
		$params = Session::get('params');

  		$response = $gateway->completePurchase($params)->send();
  		$paypalResponse = $response->getData(); // this is the raw response object
  	
  		if(isset($paypalResponse['PAYMENTINFO_0_ACK']) && $paypalResponse['PAYMENTINFO_0_ACK'] === 'Success') {

      			// Response
      			// print_r($paypalResponse);
  		
  		} else {
      			
      			//Failed transaction
      			
  		}

    		return View::make('result');
  	}
}