public function addComment(CommentRequest $request, $id)
 {
     if (\Auth::check()) {
         $user = \Auth::user();
         $post = \App\Post::findOrFail($id);
         $comment = new \App\Comment($request->all());
         $comment->user()->associate($user);
         $comment->post()->associate($post);
         $comment->save();
         return redirect('/post/' . $post->id);
     } else {
         return redirect('/auth/login');
     }
 }