Hello libart-seafire-representation

art/seafire/representation/metadata.hxx

@@ -0,0 +1,64 @@
+#ifndef art__seafire__representation__metadata_hxx_
+#define art__seafire__representation__metadata_hxx_
+
+#include <art/seafire/protocol/media-type.hxx>
+#include <art/seafire/protocol/rfc7232/entity-tag.hxx>
+
+#include <art/seafire/representation/concepts.hxx>
+#include <art/seafire/representation/representation.hxx>
+#include <art/seafire/representation/traits.hxx>
+
+#include <art/uri/uri.hxx>
+
+#include <chrono>
+#include <optional>
+
+namespace art::seafire::representation
+{
+
+  // etag
+  //
+  template<BasicRepresentation BR>
+  std::optional<protocol::rfc7232::entity_tag_t>
+  get_etag(BR const& rep)
+  {
+    using local_traits = traits::representation_traits<BR>;
+
+    if constexpr (local_traits::has_entity_tag_t)
+      return rep.etag();
+
+    return std::nullopt;
+  }
+
+  inline
+  std::optional<protocol::rfc7232::entity_tag_t>
+  get_etag(representation_t const& rep)
+  {
+    return rep.etag();
+  }
+
+
+  // last-modified
+  //
+  template<BasicRepresentation BR>
+  std::optional<std::chrono::system_clock::time_point>
+  get_last_modified(BR const& rep)
+  {
+    using local_traits = traits::representation_traits<BR>;
+
+    if constexpr (local_traits::has_last_modified)
+      return rep.last_modified();
+
+    return std::nullopt;
+  }
+
+  inline
+  std::optional<std::chrono::system_clock::time_point>
+  get_last_modified(representation_t const& rep)
+  {
+    return rep.last_modified();
+  }
+
+} // namespace art::seafire::representation
+
+#endif