public function addTag()
 {
     if (Request::ajax()) {
         $rules = ['add_tags' => 'required'];
         $validator = Validator::make(Input::all(), $rules);
         if ($validator->fails()) {
             return Response::json(['result' => 'failed', 'error' => $validator->getMessageBag()->toArray()]);
         } else {
             $tag = Input::get('add_tags');
             $tags_check = TagsModel::whereRaw('tags =?', array($tag))->get();
             if (count($tags_check) > 0) {
                 $message = "This tag has been exit.";
                 return Response::json(['result' => 'exit', 'message' => $message]);
             } else {
                 $tags = new TagsModel();
                 $tags->tags = Input::get('add_tags');
                 $tags->save();
                 $list = TagsModel::whereRaw(true)->orderBy('tags', 'asc')->get();
                 $countList = count($list);
                 $message = "Tag has been successfully.";
                 return Response::json(['result' => 'success', 'list' => $list, 'message' => $message, 'countList' => $countList]);
             }
         }
     }
 }