Protobuf TimeStamp UTC

Question

I try to map EF model with Protobuff model:

EF model

[Table("entries")]
public class Entry
{
    [Key]
    public Guid Uid { get; set; }
    public string Ip { get; set; }
    public DateTime Entered { get; set; }
    public string Code { get; set; }
    public int Retries { get; set; } = 0;
    public Guid? TokenUid { get; set; }
    [ForeignKey("TokenUid")]
    public Token Token { get; set; }
}

Protobuff model

message ProtoEntry {
  string ip = 1;
  google.protobuf.Timestamp Entered = 2;
  string code = 3;
  int32 retries = 4;
  string token = 5;
}

Mapping

var entries = _db.Entries
                .Include(x => x.Token)
                .Where(x => x.Ip == requestWithToken.Ip || x.Token.Text == token)
                .Select(x => new ProtoEntry
                {
                    Code = x.Code,
                    Entered = DateTime.SpecifyKind(x.Entered, DateTimeKind.Utc).ToTimestamp(),
                    Ip = x.Ip,
                    Retries = x.Retries,
                    Token = x.Token.Text
                }).ToList();

But It throws an exception:

System.ArgumentException: Conversion from DateTime to Timestamp requires the DateTime kind to be Utc (Parameter 'dateTime')

I also tried:
DateTime.SpecifyKind(x.Entered.ToUniversalTime(), DateTimeKind.Utc).ToTimestamp()

But seems it doesn't have an effect.
Can somebody help me?

Updates:

1. Query works good.

Answer 1

The problem was solved by changing Timestamp.FromDateTime() to Timestamp.FromDateTimeOffset().

Official Google .NET library for protobuff contains built-in extension for datetime types:

public static Timestamp ToTimestamp(this DateTime dateTime)
{
     return Timestamp.FromDateTime(dateTime);
}

which is broken for me.