MC-38770: Exception during initialization is cacheable

- fixed

Author: Oleksandr Dubovyk

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

@@ -386,7 +386,7 @@ private function initErrorHandler()
         $handler = new ErrorHandler();
         set_error_handler([$handler, 'handler']);
     }
-    
+
     /**
      * Getter for error code
      *
@@ -428,9 +428,13 @@ public function isDeveloperMode()
      */
     protected function terminate(\Throwable $e)
     {
-
+        /** @var \Magento\Framework\HTTP\PhpEnvironment\Response $response */
+        $response = $this->objectManager->get(\Magento\Framework\HTTP\PhpEnvironment\Response::class);
+        $response->clearHeaders();
+        $response->setHttpResponseCode(500);
+        $response->setHeader('Content-Type', 'text/plain');
         if ($this->isDeveloperMode()) {
-            echo $e;
+            $response->setBody($e);
         } else {
             $message = "An error has happened during application run. See exception log for details.\n";
             try {
@@ -441,8 +445,9 @@ protected function terminate(\Throwable $e)
             } catch (\Exception $e) {
                 $message .= "Could not write error message to log. Please use developer mode to see the message.\n";
             }
-            echo $message;
+            $response->setBody($message);
         }
+        $response->sendResponse();
         exit(1);
     }
     // phpcs:enable