Function UpdateObjectMetadata

getting-started/gcs_indexing.cc:156–167

std::size_t ColumnCount() { return Columns().size(); }

spanner::Mutation UpdateObjectMetadata(gcs::ObjectMetadata const& object) {
  auto const& columns = Columns();
  std::vector<spanner::Value> values(columns.size());
  std::transform(columns.begin(), columns.end(), values.begin(),
                 [&object](auto const& p) {
                   auto const& [name, to_value] = p;
                   return to_value(object);
                 });
  return spanner::InsertOrUpdateMutationBuilder("gcs_objects", Names())
      .AddRow(std::move(values))
      .Build();
}

std::string GetEnv(char const* var) {
  auto const* value = std::getenv(var);