adding more informative error message to backend

Classes/Controller/AbstractProtectedBeController.php

@@ -14,7 +14,9 @@ namespace TYPO3\Election\Controller;
  * The TYPO3 project - inspiring people to share!
  */
 
+use Doctrine\Common\Util\Debug;
 use TYPO3\CMS\Core\Messaging\AbstractMessage;
+use TYPO3\CMS\Extbase\Utility\DebuggerUtility;
 use TYPO3\CMS\Extbase\Utility\LocalizationUtility;
 
 /**
@@ -41,4 +43,38 @@ abstract class AbstractProtectedBeController extends AbstractBeController
      * @return int
      */
     abstract protected function getRequiredUserGroup();
+
+    protected function errorAction()
+    {
+        $this->clearCacheOnError();
+
+        $message="";
+        foreach ($this->arguments->getValidationResults()->getFlattenedErrors() as $propertyPath => $errors) {
+            foreach ($errors as $error) {
+                $message .= PHP_EOL. 'Error for ' . $propertyPath . ': ' . $error->render();
+            }
+        }
+
+        $errorFlashMessage = $this->getErrorFlashMessage();
+        if ($errorFlashMessage !== FALSE) {
+            $errorFlashMessageObject = new \TYPO3\CMS\Core\Messaging\FlashMessage(
+                $errorFlashMessage." ".$message,
+                '',
+                \TYPO3\CMS\Core\Messaging\FlashMessage::ERROR
+            );
+            $this->controllerContext->getFlashMessageQueue()->enqueue($errorFlashMessageObject);
+        }
+        $referringRequest = $this->request->getReferringRequest();
+        if ($referringRequest !== NULL) {
+            $originalRequest = clone $this->request;
+            $this->request->setOriginalRequest($originalRequest);
+            $this->request->setOriginalRequestMappingResults($this->arguments->getValidationResults());
+            $this->forward($referringRequest->getControllerActionName(), $referringRequest->getControllerName(), $referringRequest->getControllerExtensionName(), $referringRequest->getArguments());
+        }
+        DebuggerUtility::var_dump($this->request['nominee.image']);
+        $message = 'An error occurred while trying to call ' . get_class($this) . '->' . $this->actionMethodName . '().' . PHP_EOL;
+        return $message;
+
+    }
+
 }