Magento 2 : How to redirect from a observer without exit or die (as it's not allowed by magento standards)

Question

I know of a couple of ways of redirecting to a given URL in observer but all of them uses exit or die and they would not work without it. So, if someone knows of a way of doing it without using exit or die then please let me know.

Answer 1

use setRedirect

<?php
namespace [Vendor]\[modulename]\Observer;
use \Magento\Framework\Event\Observer;
use \Magento\Framework\Event\ObserverInterface;
class [YourClass] implements ObserverInterface {
    protected $_responseFactory;
    protected $_redirect;
    protected $_url;
    public function __construct(
        ......
        \Magento\Framework\App\ResponseFactory $responseFactory,
        \Magento\Framework\UrlInterface $url,
        \Magento\Framework\App\Response\Http $redirect,
        ......
    ) {
        $this->_responseFactory = $responseFactory;
        $this->_url = $url;
        $this->_redirect = $redirect;

    }
    public function execute(Observer $observer) {
             $event = $observer->getEvent();
             $CustomRedirectionUrl = $this->_url->getUrl('[ModuleName]/[ModuleName]/[[Action]');
             $this->_redirect->setRedirect($CustomRedirectionUrl);

    }
}

Answer 2

Without exit or die redirecting to a given URL in observer you need to stop the dispatch event using Action::FLAG_NO_DISPATCH

namespace [Vendor]\[modulename]\Observer;

use Magento\Framework\Event\ObserverInterface;
class [YourClass] implements ObserverInterface {

    protected $urlManager;
    protected $actionFlag;
    protected $redirect;

    public function __construct(
        ......
        \Magento\Framework\UrlInterface $url,
        \Magento\Framework\App\ActionFlag $actionFlag,
        \Magento\Framework\App\Response\RedirectInterface $redirect,
        ......
    ) {
        $this->urlManager = $url;
        $this->actionFlag = $actionFlag;
        $this->redirect = $redirect;

    }
    public function execute(\Magento\Framework\Event\Observer $observer) {
            $controller = $observer->getControllerAction();
            // stop the dispatch event. 
            $this->actionFlag->set('', \Magento\Framework\App\Action\Action::FLAG_NO_DISPATCH, true);
            //YOUR-ACTION eq to ex. for create acount '*/*/create'
            $defaultUrl = $this->urlManager->getUrl('YOUR-ACTION', ['_secure' => true]);
            $controller->getResponse()->setRedirect($this->redirect->error($defaultUrl));

    }
}