public function initDeliveryExecution() {
        try {
            $deliveryExecution = $this->_initDeliveryExecution();
            //if authorized we can move to this URL.
            $this->redirect(_url('runDeliveryExecution', null, null, array('deliveryExecution' => $deliveryExecution->getIdentifier())));
        } catch (UnAuthorizedException $e) {
            return $this->redirect($e->getErrorPage());
        } catch (common_exception_Unauthorized $e) {
            return $this->returnJson([
                'success' => false,
                'message' => __('You are no longer allowed to take this test')
            ], 403);
        }
    }