Install-Package Zaabee.AspNetCoreProtobuf

public void ConfigureServices(IServiceCollection services)
{
  services.AddMvc(options => { options.AddProtobufSupport(); });
}

[ProtoContract]
public class TestDto
{
  [ProtoMember(1)] public Guid Id { get; set; }
  [ProtoMember(2)] public string Name { get; set; }
  [ProtoMember(3)] public DateTime CreateTime { get; set; }
  [ProtoMember(4)] public List<TestDto> Kids { get; set; }
  [ProtoMember(5)] public long Tag { get; set; }
  [ProtoMember(6)] public TestEnum Enum { get; set; }
}

public enum TestEnum
{
  Apple,
  Banana,
  Pear
}

public class AspNetCoreProtobufTest
{
  private readonly TestServer _server;
  private readonly HttpClient _client;

  public AspNetCoreProtobufTest()
  {
    _server = new TestServer(
      new WebHostBuilder()
        .UseKestrel()
        .UseStartup<Startup>());
    _client = _server.CreateClient();
  }

  [Fact]
  public void Test()
  {
    // HTTP Post with Protobuf Response Body
    _client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/x-protobuf"));

    var dtos = GetDtos();
    var stream = new MemoryStream();
    ProtoBuf.Serializer.Serialize(stream, dtos);

    HttpContent httpContent = new StreamContent(stream);

    // HTTP POST with Protobuf Request Body
    var responseForPost = _client.PostAsync("api/Values", httpContent);

    var result = ProtoBuf.Serializer.Deserialize<List<TestDto(
      responseForPost.Result.Content.ReadAsStreamAsync().Result);

    Assert.True(CompareDtos(dtos,result));
  }

  private static bool CompareDtos(List<TestDto> lstOne, List<TestDto> lstTwo)
  {
    lstOne = lstOne "0",
        Enum = TestEnum.Apple,
        Kids = new List<TestDto>
        {
          new TestDto
          {
            Id = Guid.NewGuid(),
            Tag = long.MaxValue - 1,
            CreateTime = DateTime.Now,
            Name = "00",
            Enum = TestEnum.Banana
          },
          new TestDto
          {
            Id = Guid.NewGuid(),
            Tag = long.MaxValue - 2,
            CreateTime = DateTime.Now,
            Name = "01",
            Enum = TestEnum.Pear
          }
        }
      },
      new TestDto
      {
        Id = Guid.NewGuid(),
        Tag = long.MaxValue - 3,
        CreateTime = DateTime.Now,
        Name = "1",
        Enum = TestEnum.Apple,
        Kids = new List<TestDto>
        {
          new TestDto
          {
            Id = Guid.NewGuid(),
            Tag = long.MaxValue - 4,
            CreateTime = DateTime.Now,
            Name = "10",
            Enum = TestEnum.Banana
          },
          new TestDto
          {
            Id = Guid.NewGuid(),
            Tag = long.MaxValue - 5,
            CreateTime = DateTime.Now,
            Name = "11",
            Enum = TestEnum.Pear
          }
        }
      }
    };
  }
}