public static void WriteAccessControlHeaders(this HttpMessageWriter writer)
{
writer.WriteAccessControlAllowOrigin(true);
writer.WriteAccessControlAllowCredentials(true);
writer.WriteAccessControlAllowHeaders(accessControlAllowHeaders);
writer.WriteAccessControlExposeHeaders(accessControlExposeHeaders);
writer.WriteAccessControlAllowMethods(Methods.Get, Methods.Post, Methods.Options);
}