Skip to content

How do I send a google.protobuf.Value object using protobuf-net.Grpc and code-first? #338

Open
@glazkovalex

Description

@glazkovalex

The protobuf format has the type google.protobuf.Value described in Create Protobuf messages for .NET apps.
There is also a Google.Protobuf.WellKnownTypes.Value type in the Google.Protobuf, Version=3.28.0.0 library.

I can send google.protobuf.Value with a message described by such a proto-file:

syntax = "proto3";
import "google/protobuf/struct.proto";
import "google/protobuf/empty.proto";

service Greeter {
  rpc SayHello (google.protobuf.Empty) returns (Status);
}

message Status {
    google.protobuf.Value data = 3;
}

As a result, I will get a generated dot with a "data" field of the type Google.Protobuf.WellKnownTypes.Value. I can assign an arbitrary JsonDocument to this "data" in the following way and everything will be transmitted perfectly.

var dto = new Status();
dto.Data = Google.Protobuf.WellKnownTypes.Value.Parser.ParseJson(myJsonDocument.RootElement.ToString())

I used protobuf-net.Grpc and applied code-first by creating such a dto with the field Google.Protobuf.WellKnownTypes.Value

[DataContract]
public class ObjectTypeDto
{
    [DataMember(Order = 1)]
    public Google.Protobuf.WellKnownTypes.Value Data { get; set; }
}

If I pass my myJsonDocument through it as before, I get an exception: System.InvalidOperationException: No serializer defined for type: Google.Protobuf.WellKnownTypes.Value

I used the tool https://protogen.marcgravell.com and generated the following dto from the above proto file:

// <auto-generated>
//   This file was generated by a tool; you should avoid making direct changes.
//   Consider using 'partial classes' to extend these types
//   Input: my.proto
// </auto-generated>
#region Designer generated code
#pragma warning disable CS0612, CS0618, CS1591, CS3021, IDE0079, IDE1006, RCS1036, RCS1057, RCS1085, RCS1192
[global::ProtoBuf.ProtoContract()]
public partial class Status : global::ProtoBuf.IExtensible
{
    private global::ProtoBuf.IExtension __pbn__extensionData;
    global::ProtoBuf.IExtension                 
    global::ProtoBuf.IExtensible.GetExtensionObject(bool createIfMissing)
    => global::ProtoBuf.Extensible.GetExtensionObject(ref     
    __pbn__extensionData, createIfMissing);

    [global::ProtoBuf.ProtoMember(3, Name = @"data")]
    public global::Google.Protobuf.WellKnownTypes.Value Data { get; set; }

}

[global::System.ServiceModel.ServiceContract(Name = @"Greeter")]
public partial interface IGreeter
{
    global::System.Threading.Tasks.ValueTask<Status>     
SayHelloAsync(global::ProtoBuf.Grpc.CallContext context = default);
}
#pragma warning restore CS0612, CS0618, CS1591, CS3021, IDE0079, IDE1006, RCS1036, RCS1057, RCS1085, RCS1192
#endregion

When I try to return the result from the method in this dto, I get the same exception.

How do I send a google.protobuf.Value (Google.Protobuf.WellKnownTypes.Value) object using protobuf-net.Grpc and code-first?

Metadata

Metadata

Assignees

No one assigned

    Labels

    No labels
    No labels

    Type

    No type

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions