MyObserver.php

<?php

namespace Vodex\Logger\Observer;
/**
 * @category   Logger
 * @package    Vodex_Logger
 * @author     info@vodex.co.id
 * @website    https://vodex.co.id
 * @license    http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */
class MyObserver implements ObserverInterface
{
    /**
     * @var Data
     */
  protected $authSession;
  
  public function __construct(
        ...
        \Magento\Backend\Model\Auth\Session $authSession
    )
    {
        ...
        $this->authSession = $authSession;
        ...
    }
  public function getCurrentUser()
    {
        return $this->authSession->getUser();
    }

  public function execute(Observer $observer)
    {
        ...
          
        /**
         * Get User Condition
         * Check if User Logged In
         */
        if ($this->authSession->isLoggedIn()) {
            $userEmail = $this->authSession->getUser()->getEmail();
        } else {
            $userEmail = 'notloggedin';
        }
    
        ...