extract common behavior

include/providers/s3/s3_provider.hpp

@@ -49,10 +49,6 @@ private:
                                       const std::string &object_name) const
       -> api_error;
 
-  [[nodiscard]] auto create_directory_impl(const std::string &api_path,
-                                           api_meta_map &meta)
-      -> api_error override;
-
   [[nodiscard]] auto create_file_extra(const std::string &api_path,
                                        api_meta_map &meta)
       -> api_error override;
@@ -75,14 +71,19 @@ private:
                   std::optional<std::string> prefix = std::nullopt) const
       -> bool;
 
+protected:
+  [[nodiscard]] auto create_directory_impl(const std::string &api_path,
+                                           api_meta_map &meta)
+      -> api_error override;
+
+  [[nodiscard]] auto get_directory_items_impl(const std::string &api_path,
+                                              directory_item_list &list) const
+      -> api_error override;
+
 public:
   [[nodiscard]] auto get_directory_item_count(const std::string &api_path) const
       -> std::uint64_t override;
 
-  [[nodiscard]] auto get_directory_items(const std::string &api_path,
-                                         directory_item_list &list) const
-      -> api_error override;
-
   [[nodiscard]] auto get_file(const std::string &api_path, api_file &file) const
       -> api_error override;