Introduction

This guide gives an example how to work with sessions in X-Cart. X-Cart identifies a session data by a value stored in xid cookie – unless changed by decoration of \XLite\Core\Session class.

For the sake of example, we will create a module with a page cart.php?target=session_demo and this page can be called with the session_value parameter. For the very first time this page will display the Session value has not been specified yet message and it will remain the same until the session_value parameter is passed. Once it is passed, the page will display the Session value is: {session_value} message. Even if you open this page without session_value parameter after that, the message Session value is: {session_value} message will be displayed with the latest session_value submitted.

Implementation

We start with creating an empty module with developer ID XCExample and module ID SessionDemo. Then we create a page cart.php?target=session_demo in our module. For that we create:

• an empty controller class \XLite\Module\XCExample\SessionDemo\Controller\Customer\SessionDemo:

  <?php
  // vim: set ts=4 sw=4 sts=4 et:
  
  namespace XLite\Module\XCExample\SessionDemo\Controller\Customer;
  
  /**
   * SessionDemo
   */
  class SessionDemo extends \XLite\Controller\Customer\ACustomer
  {
  }    

• a page viewer class \XLite\Module\XCExample\SessionDemo\View\Page\Customer\SessionDemo with the following content: 

  <?php
  // vim: set ts=4 sw=4 sts=4 et:
  
  namespace XLite\Module\XCExample\SessionDemo\View\Page\Customer;
  
  /**
  * SessionDemoPage
  *
  * @ListChild (list="center", zone="customer")
  */
  class SessionDemoPage extends \XLite\View\AView
  {
      
      /**
     * Return list of allowed targets
       */
    public static function getAllowedTargets()
      {
          return array_merge(parent::getAllowedTargets(), array('session_demo'));
    }
    
      /**
     * Return widget default template
       */
    public function getDefaultTemplate()
      {
          return 'modules/XCExample/SessionDemo/page/session_demo/body.twig';
    }
  }

• an empty page template skins/customer/modules/XCExample/SessionDemo/page/session_demo/body.twig.

If there is session_value parameter in request to cart.php?target=session_demo page, we will save it to the session variable. To achieve that we are going to implement custom handleRequest() method in our controller class \XLite\Module\XCExample\SessionDemo\Controller\Customer\SessionDemo: 

public function handleRequest()
{
    $sessionValue = \XLite\Core\Request::getInstance()->session_value;

    if (!empty($sessionValue)) {
        \XLite\Core\Session::getInstance()->session_value = $sessionValue;
    }

    parent::handleRequest();
}

The code that saves the session_value param into a session is \XLite\Core\Session::getInstance()->session_value = $sessionValue;. As you can see, saving variable into a session is as simple as assigning a value.

Now, we need to add a method to our controller that will fetch a value of this session variable. It will be as follows: 

public function getSessionValue() 
{
    if (!empty(\XLite\Core\Session::getInstance()->session_value)) {
        return \XLite\Core\Session::getInstance()->session_value;
    }

    return null;
}  

By default it returns an null, but if there is any value stored in the session_value session variable, then it will return this value.

The final version of \XLite\Module\XCExample\SessionDemo\Controller\Customer\SessionDemo class will be as follows: 

<?php
// vim: set ts=4 sw=4 sts=4 et:

namespace XLite\Module\XCExample\SessionDemo\Controller\Customer;

/**
 * SessionDemo
 */
class SessionDemo extends \XLite\Controller\Customer\ACustomer
{
    public function handleRequest()
    {
        $sessionValue = \XLite\Core\Request::getInstance()->session_value;

        if (!empty($sessionValue)) {
            \XLite\Core\Session::getInstance()->session_value = $sessionValue;
        }

        parent::handleRequest();
    }

    public function getSessionValue() 
    {
        if (!empty(\XLite\Core\Session::getInstance()->session_value)) {
            return \XLite\Core\Session::getInstance()->session_value;
        }

        return null;
    }    
}

Now we need to define display of our page and the mod will be done. We go to the skins/customer/modules/Tony/SessionDemo/page/session_demo/body.twig template and define its content as follows: 

{% if this.getSessionValue() %}
Session value is: {{ this.getSessionValue() }}
{% else %}
Session value has not been specified yet
{% endif %}

If getSessionValue() returns non-empty value, we display the Session value is: {session_value} message, otherwise we display the message Session value has not been specified yet.

That is it. Now we can check the results. Go to your cart.php?target=session_demo page and you will see the message that session variable is not defined yet:

Then, try to open this page as cart.php?target=session_demo&session_value=foo and you will see the following result:

If you try to open the same page as cart.php?target=session_demo with session_value parameter, you will still see the result with session variable defined:

If you want to see the initial message, you will have to clean up your cookies.

Module example

This module pack can be downloaded from here: XCExample-SessionDemo-v5_3_0.tar