Update ClearCacheForm.php

Closes #3182669

src/Form/ClearCacheForm.php

@@ -110,20 +110,27 @@ class ClearCacheForm extends FormBase {
       // Clear cache by particular tags.
       case self::CACHE_CLEAR_TYPE_TAG:
         $tags = explode(' ', trim($form_state->getValue('arguments')));
-        $this->cacheManager->purgeTags($tags);
+        $result = $this->cacheManager->purgeTags($tags);
         break;
 
       // Flush all cache of the site.
       case self::CACHE_CLEAR_TYPE_FULL:
-        $this->cacheManager->flushAllCaches();
+        $result = $this->cacheManager->flushAllCaches();
         break;
 
       // Clear cache by URL.
       case self::CACHE_CLEAR_TYPE_URI:
-        $this->cacheManager->purgeUri($form_state->getValue('arguments'));
+        $result = $this->cacheManager->purgeUri($form_state->getValue('arguments'));
         break;
     }
 
+    if (empty($result)) {
+      $this->messenger()->addError($this->t("The site wasn't banned. Please read Database logs by this channel: adv varnish."));
+    }
+    else {
+      $this->messenger()->addStatus($this->t('Site banned.'));
+    }
+
   }
 
   /**