Magento 2 get session variable on checkout not working

Question

I have been struggling with this issue like 2 days, and I don't understand why it's happening.

This is what I'm doing:

1- Unset session variable in case it exists and Create a new session variable 2- Add value to session variable 3- get the session variable on Checkout

The 3 step is not working, sometimes it works sometimes not, don't know why.

Here is my code:

Helper of session variables:

<?php

namespace Vendor\Application\Helper;


class SessionUniqueId extends \Magento\Framework\App\Helper\AbstractHelper
{
    
    protected $_coreSession;

    public function __construct(
        \Magento\Checkout\Model\Session $coreSession
    ) {
        $this->_coreSession = $coreSession;
    }

    public function startSession($uniqueId){
        $this->_coreSession->start();
        $this->_coreSession->setUniqueid($uniqueId);
    }

    public function getSession(){
        $this->_coreSession->start();
        return $this->_coreSession->getUniqueid();
    }

    public function deleteSession(){
        $this->_coreSession->start();
        return $this->_coreSession->unsUniqueid();
    }

}

1- Unset and set new variable session

public function setSession($uniqueid){
        $this->_sessionHelper->startSession($uniqueid);
        $this->_logger->info("Empieza la sesión de ".$uniqueid);
    }


    public function unsetSession(){
        $this->_logger->info("Destruyo la sesión en el block ");
        return $this->_sessionHelper->deleteSession();
    }

2- I call this 2 methods on a template (phtml) this part works fine

    $params = $block->getData('params');
    $uniqueid = $block->serializeData($params['uniqueId']);
    $block->unsetSession();
    $block->setSession($params['uniqueId']);

3- I try to get uniqueId variable session on this event: sales_order_place_after, by calling my helper

public function execute(\Magento\Framework\Event\Observer $observer){
        //Get UNIQUE ID of term employee
        $uniqueId = $this->_sessionHelper->getSession();
        //Get Order data
        $order = $observer->getOrder();
        $orderNumber = $order->getIncrementId();
        $orderGrandTotal = $order->getGrandTotal();
        $this->_logger->info("Order Number: ".$orderNumber);
        $this->_logger->info("Order Grand Total: ".$orderGrandTotal);
        $this->_logger->info("Unique ID: ".$uniqueId); //here is empty [][]
       
        $this->_sessionHelper->deleteSession();
    }

It's practically empty sometimes, when I place an order.

What could it be?

Thanks!

Answer 1

You can save data to Magento's default session without creating a separate session

protected $_checkoutSession;
public function __construct(
    ....
    public function __construct(
    \Magento\Checkout\Model\Session $checkoutSession
) {

    $this->_checkoutSession = $checkoutSession;
}

public function getCheckoutSession() 
{
    return $this->_checkoutSession;
}

You set a value : $this->getCheckoutSession()->setVarValue('someValueHere');