MAGETWO-34988: Implement exception handling in dispatch() method

Author: vpaladiychuk

app/etc/di.xml

@@ -1074,6 +1074,12 @@
             </argument>
         </arguments>
     </type>
+    <type name="Magento\Framework\App\FrontController">
+        <arguments>
+            <argument name="appState" xsi:type="object">Magento\Framework\App\State\Proxy</argument>
+            <argument name="messageManager" xsi:type="object">Magento\Framework\Message\ManagerInterface\Proxy</argument>
+        </arguments>
+    </type>
     <type name="Magento\Framework\Webapi\Rest\Request\DeserializerFactory">
         <arguments>
             <argument name="deserializers" xsi:type="array">

lib/internal/Magento/Framework/App/FrontController.php

@@ -67,7 +67,7 @@ public function dispatch(RequestInterface $request)
         $routingCycleCounter = 0;
         $result = null;
         while (!$request->isDispatched() && $routingCycleCounter++ < 100) {
-            $result = $this->matchAction($request);
+            $result = $this->processRequest($request);
         }
         \Magento\Framework\Profiler::stop('routers_match');
         if ($routingCycleCounter > 100) {
@@ -81,23 +81,27 @@ public function dispatch(RequestInterface $request)
      *
      * @param \Exception $e
      * @param \Magento\Framework\App\ActionInterface $actionInstance
-     * @param string $message
      * @return \Magento\Framework\Controller\Result\Redirect
      */
-    protected function handleException($e, $actionInstance, $message)
+    protected function handleException($e, $actionInstance)
     {
-        $this->messageManager->addError($message);
+        $needToMaskDisplayMessage = !($e instanceof \Magento\Framework\Exception\LocalizedException)
+            && ($this->appState->getMode() != State::MODE_DEVELOPER);
+        $displayMessage = $needToMaskDisplayMessage
+            ? (string)new \Magento\Framework\Phrase('An error occurred while processing your request')
+            : $e->getMessage();
+        $this->messageManager->addError($displayMessage);
         $this->logger->critical($e->getMessage());
         return $actionInstance->getDefaultRedirect();
     }
 
     /**
-     * Match action, dispatch
+     * Route request and dispatch it
      *
      * @param RequestInterface $request
-     * @return \Magento\Framework\Controller\Result\Redirect
+     * @return ResponseInterface|\Magento\Framework\Controller\ResultInterface|null
      */
-    protected function matchAction(RequestInterface $request)
+    protected function processRequest(RequestInterface $request)
     {
         $result = null;
         /** @var \Magento\Framework\App\RouterInterface $router */
@@ -107,24 +111,20 @@ protected function matchAction(RequestInterface $request)
                 if ($actionInstance) {
                     $request->setDispatched(true);
                     $actionInstance->getResponse()->setNoCacheHeaders();
-                    $result = $actionInstance->dispatch($request);
+                    try {
+                        $result = $actionInstance->dispatch($request);
+                    } catch (Action\NotFoundException $e) {
+                        throw $e;
+                    } catch (\Exception $e) {
+                        $result = $this->handleException($e, $actionInstance);
+                    }
                     break;
                 }
             } catch (Action\NotFoundException $e) {
                 $request->initForward();
                 $request->setActionName('noroute');
                 $request->setDispatched(false);
                 break;
-            } catch (\Magento\Framework\Exception\LocalizedException $e) {
-                $result = $this->handleException($e, $actionInstance, $e->getMessage());
-                break;
-            } catch (\Exception $e) {
-                // @todo Message should be clarified
-                $message = $this->appState->getMode() == State::MODE_DEVELOPER
-                    ? $e->getMessage()
-                    : (string)new \Magento\Framework\Phrase('An error occurred while processing your request');
-                $result = $this->handleException($e, $actionInstance, $message);
-                break;
             }
         }
         return $result;