Bidirectional Streaming with gRPC in C#

.proto

syntax = "proto3";

import "google/protobuf/timestamp.proto";

option csharp_namespace = "GrpcBidiStearming";

package greet;

service Greeter {
  rpc SayHello (stream HelloRequest) returns (stream HelloReply);
}

message HelloRequest {
  string name = 1;
  google.protobuf.Timestamp timestamp = 2;
}

message HelloReply {
  string message = 1;
  google.protobuf.Timestamp timestamp = 2;
}

Server

public override async Task SayHello(IAsyncStreamReader<HelloRequest> requestStream,
    IServerStreamWriter<HelloReply> responseStream, ServerCallContext context)
{
    while (await requestStream.MoveNext() && !context.CancellationToken.IsCancellationRequested)
    {
        Console.WriteLine("Request : {0}, Timestamp : {1}", requestStream.Current.Name,
            requestStream.Current.Timestamp);

        await responseStream.WriteAsync(new HelloReply
        {
            Message = $"Hello {requestStream.Current.Name}",
            Timestamp = Timestamp.FromDateTime(DateTime.UtcNow)
        });
        
        Console.WriteLine("Response : {0}, Timestamp : {1}", requestStream.Current.Name,
            requestStream.Current.Timestamp);
    }
}

Client

static async Task Main(string[] args)
{
    using var channel = GrpcChannel.ForAddress("http://localhost:5000");
    var client = new Greeter.GreeterClient(channel);

    CancellationToken cancellationToken = new CancellationToken(false);
    var response = client.SayHello(new CallOptions(null, null, cancellationToken));


    for (int i = 0; i < 100; i++)
    {
        var timestamp = Timestamp.FromDateTime(DateTime.UtcNow);
        await response.RequestStream.WriteAsync(new HelloRequest
        {
            Name = "Mahmood",
            Timestamp = timestamp
        });

        Console.WriteLine(String.Format("Request : {0}", timestamp.ToString()));

        await response.ResponseStream.MoveNext();

        Console.WriteLine(String.Format("Response : {0}, Timestamp : {1}",
            response.ResponseStream.Current.Message,
            response.ResponseStream.Current.Timestamp));

        await Task.Delay(1000);
    }
}

References
https://www.youtube.com/watch?v=wY4nMSUF9e0&list=PLUOequmGnXxPOlhyA57ijmEyOeVmYQt32&index=4

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