How to redirect a visitor in an observer?

dmitry_fedyuk · March 4, 2016, 1:46am

magento/magento2/blob/cf7df72/app/code/Magento/Captcha/etc/frontend/events.xml#L9-L11


<event name="controller_action_predispatch_contact_index_post">
    <observer name="captcha_contact_us_form" instance="Magento\Captcha\Observer\CheckContactUsFormObserver" />
</event>

github.com

magento/magento2/blob/cf7df72/app/code/Magento/Captcha/Observer/CheckContactUsFormObserver.php#L27-L30


/**
 * @var \Magento\Framework\App\Response\RedirectInterface
 */
protected $redirect;

github.com

magento/magento2/blob/cf7df72/app/code/Magento/Captcha/Observer/CheckContactUsFormObserver.php#L48-L48


\Magento\Framework\App\Response\RedirectInterface $redirect,

github.com

magento/magento2/blob/cf7df72/app/code/Magento/Captcha/Observer/CheckContactUsFormObserver.php#L58-L76


/**
 * Check CAPTCHA on Contact Us page
 *
 * @param \Magento\Framework\Event\Observer $observer
 * @return void
 */
public function execute(\Magento\Framework\Event\Observer $observer)
{
    $formId = 'contact_us';
    $captcha = $this->_helper->getCaptcha($formId);
    if ($captcha->isRequired()) {
        /** @var \Magento\Framework\App\Action\Action $controller */
        $controller = $observer->getControllerAction();
        if (!$captcha->isCorrect($this->captchaStringResolver->resolve($controller->getRequest(), $formId))) {
            $this->messageManager->addError(__('Incorrect CAPTCHA.'));
            $this->_actionFlag->set('', \Magento\Framework\App\Action\Action::FLAG_NO_DISPATCH, true);
            $this->redirect->redirect($controller->getResponse(), 'contact/index/index');
        }
    }

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