Custom Session Variable Not Saving

Question

I'm having an issue with session variables saving after a redirect. Here's a mock of the relevant code:

class Company_X_Model_Session extends Mage_Core_Model_Session_Abstract {
    const KEY_QUOTE = 'quote';

    protected function _construct() {
        $this->init('company_x');
    }

    public function getQuote() {
        if (!$this->hasData(self::KEY_QUOTE)) {

            $quote = Mage::getModel('sales/quote')->setStoreId(Mage::app()->getStore()->getId());
            /* @var $quote Mage_Sales_Model_Quote */

            if ($this->getQuoteId()) {
                $quote->load($this->getQuoteId());
            }
            $this->setData(self::KEY_QUOTE, $quote);
        }
        return $this->getData(self::KEY_QUOTE);
    }

    public function clear() {
        $this->_quote = null;
        $this->setQuoteId(null);
        $this->setLastSuccessQuoteId(null);
        return parent::clear();
    }
}

In the controller class:

class Company_X_SomeController extends Other_Company_SomeController {

    protected function relevantAction() {

        $session = Mage::getSingleton('company_x/session');
        /* @var $session Company_X_Model_Session */

        $quote = $session->getQuote();
        /* @var $quote Mage_Sales_Model_Quote */

        $payment = $quote->getPayment();
        $payment->importData(array('method' => 'paypal_express'));

        /// all sorts of interesting quote-setting-up code here         

        $quote->collectTotals()->save();

        /// This variable is not saving properly
        $session->setQuoteId($quote->getId());

        $this->_redirectUrl($quote->getPayment()->getCheckoutRedirectUrl());
    }
}

Controller that the redirect hits:

class Company_X_ExpressController extends Mage_Paypal_ExpressController {

    protected function _getQuote() {
        if(!$this->_quote) {
            $this->_quote = $this->_getCheckoutSession()->getQuote();
        }
        return $this->_quote;
    }

    protected function _getCheckoutSession() {

        /// quote_id is not printed here.
        print_r(Mage::getSingleton('company_x/session')->getData());

        return Mage::getSingleton('company_x/session');
    }

}

Can anyone shed some light on why the quote_id variable is not persisting after the redirect?

Edit 1:

In the first controller:

Company_X_Model_Session Object
(
    [_skipSessionIdFlag:protected] => 
    [_sessionHosts:protected] => Array
        (
            [company.x.local] => 1
        )

    [_data:protected] => Array
        (
            [_session_validator_data] => Array
                (
                    [remote_addr] => 10.0.2.21
                    [http_via] => 
                    [http_x_forwarded_for] => 
                    [http_user_agent] => Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.116 Safari/537.36
                )

            [quote_id] => 445
        )

    [_hasDataChanges:protected] => 
    [_origData:protected] => 
    [_idFieldName:protected] => 
    [_isDeleted:protected] => 
    [_oldFieldsMap:protected] => Array
        (
        )

    [_syncFieldsMap:protected] => Array
        (
        )

)

In the redirect controller:

Company_X_Model_Session Object
(
    [_skipSessionIdFlag:protected] => 
    [_sessionHosts:protected] => Array
        (
            [company.x.local] => 1
        )

    [_data:protected] => Array
        (
            [_session_validator_data] => Array
                (
                    [remote_addr] => 10.0.2.21
                    [http_via] => 
                    [http_x_forwarded_for] => 
                    [http_user_agent] => Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.116 Safari/537.36
                )

        )

    [_hasDataChanges:protected] => 
    [_origData:protected] => 
    [_idFieldName:protected] => 
    [_isDeleted:protected] => 
    [_oldFieldsMap:protected] => Array
        (
        )

    [_syncFieldsMap:protected] => Array
        (
        )

)

Resolution:

The Other_Company_SomeController class had overridden the preDispatch method and did not properly call through to the parent class.

Answer 1

I've come to the conclusion that the Other_Company_SomeController class had its preDispatch method overridden and was not properly calling through to the parent method.

This caused the entire problem. Thanks to those who've invested their time and effort into helping me figure this out.

Answer 2

So as we found out in the comment using $session->getSessionId();, you have two different session ids in your controller.

After checking your code again, the error is so small it's hard to find it.

The reason behind that is because your constructor is missing an underscore, so instead of:

protected function _construct() {
    $this->init('company_x');
}

It should be:

protected function __construct() {
    $this->init('company_x');
}