@NotNull(message = "repo is never NULL")
public Repo create(
@NotNull(message = "json can't be NULL") final JsonObject json
) throws IOException {
final String name = json.getString("name");
final Coordinates coords = new Coordinates.Simple(this.self, name);
this.storage.apply(
new Directives().xpath(this.xpath()).add("repo")
.attr("coords", coords.toString())
.add("name").set(name).up()
.add("description").set("test repository").up()
.add("private").set("false").up()
);
final Repo repo = this.get(coords);