public class Log
{
    public int Id { get; set; }
    public string Action { get; set; }
    public string Message { get; set; }
}

public class LogIndex : AbstractIndexCreationTask<Log>
{
    public LogIndex()
    {
        Map = xs => from x in xs
                    select new
                    {
                        x.Id,
                        x.Action,
                        x.Message
                    };
    }
}