public static bool IsNotModified(this HttpRequestMessage requestMessage, IHaveVersion versionable)
{
if (!requestMessage.Headers.IfNoneMatch.Any()) return false;
var etag = requestMessage.Headers.IfNoneMatch.First().Tag;
return string.Format("\"{0}\"", versionable.Version) == etag;
}
private static int UpdateVersion(IHaveVersion item, int defaultVersion) => item?.Version + 1 ?? defaultVersion;