gRPC client request streaming: - "The client reset the request stream."

I am trying to implement request streaming from my python client to my C# server using gRPC. This is my protofile:

    syntax = "proto3";
        
    service PerceiveAPIDataService {
      rpc UploadResource (stream UploadResourceRequest) returns (UploadResourceResponse);
    }
    
    message UploadResourceRequest {
      oneof request_data {
        ResourceChunk resource_chunk = 1;
        UploadResourceParameters parameters = 2;
      }
    }
    
    message ResourceChunk {
        bytes content = 1; 
    }
    
    message UploadResourceParameters {
        string path = 1;
    }

This is my c# implementation:

    public override async Task<UploadResourceResponse> UploadResource(IAsyncStreamReader<UploadResourceRequest> requestStream, ServerCallContext context)
    {
        if (!await requestStream.MoveNext())
        {
            throw new RpcException(new Status(StatusCode.FailedPrecondition, "No upload parameters found."));
        }

        var initialMessage = requestStream.Current;
        if (initialMessage.RequestDataCase != UploadResourceRequest.RequestDataOneofCase.Parameters)
        {
            throw new RpcException(new Status(StatusCode.FailedPrecondition, "First message must contain upload parameters."));
        }

        var path = initialMessage.Parameters.Path;
        if (string.IsNullOrWhiteSpace(path))
        {
            throw new RpcException(new Status(StatusCode.InvalidArgument, "Upload path is required."));
        }

        using (var ms = new MemoryStream())
        {
            while (await requestStream.MoveNext())
            {
                var chunk = requestStream.Current.ResourceChunk;
                if (chunk == null)
                {
                    continue;  // Skip any messages that are not resource chunks
                }

                await ms.WriteAsync(chunk.Content.ToByteArray().AsMemory(0, chunk.Content.Length));
            }

            ms.Seek(0, SeekOrigin.Begin); // Reset memory stream position to the beginning for reading during upload
            var uploadResult = await _dataService.UploadResourceAsync(path, ms);
            return new UploadResourceResponse { Succeeded = uploadResult.IsSuccessful };
        }
    }

And this is my python client code:

    def generate_request(self, data: bytearray, next_cloud_path: str) -> Generator:
        first_req = perceive_api_data_service_pb2.UploadResourceRequest(
            parameters=perceive_api_data_service_pb2.UploadResourceParameters(path=next_cloud_path)
        )
        yield first_req
        print("Sent initial request with path:", next_cloud_path)
        
        chunk_size = 2048
        total_chunks = (len(data) + chunk_size - 1) // chunk_size  # Ceiling division to get total number of chunks
        print(f"Data size: {len(data)} bytes, chunk size: {chunk_size} bytes, total chunks: {total_chunks}")
        
        for i in range(0, len(data), chunk_size):
            chunk = data[i:i+chunk_size]
            yield perceive_api_data_service_pb2.UploadResourceRequest(
                resource_chunk=perceive_api_data_service_pb2.ResourceChunk(content=chunk)
            )
            print(f"Sent chunk {((i // chunk_size) + 1)} of {total_chunks}")
    
    async def upload_file(self, data: bytearray, next_cloud_path: str) -> bool:
        
        async with grpc.aio.insecure_channel("localhost:5228") as channel:
            stub = perceive_api_data_service_pb2_grpc.PerceiveAPIDataServiceStub(channel)
            
            request_iterator = self.generate_request(data, next_cloud_path)
            
            response = await stub.UploadResource(request_iterator)
                        
            return response.succeeded

The error I get on the server is this:

Grpc.AspNetCore.Server.ServerCallHandler: Error: Error when executing service method 'UploadResource'.

System.IO.IOException: The client reset the request stream. at System.IO.Pipelines.Pipe.GetReadResult(ReadResult& result) at System.IO.Pipelines.Pipe.GetReadAsyncResult()

And the error I get on the client is this:

File "C:\Users\user_name\AppData\Local\Programs\Python\Python311\Lib\site-packages\grpc\aio_call.py", line 690, in _conduct_rpc serialized_response = await self._cython_call.stream_unary( ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "src\python\grpcio\grpc_cython_cygrpc/aio/call.pyx.pxi", line 458, in stream_unary File "src\python\grpcio\grpc_cython_cygrpc/aio/callback_common.pyx.pxi", line 166, in _receive_initial_metadata File "src\python\grpcio\grpc_cython_cygrpc/aio/callback_common.pyx.pxi", line 99, in execute_batch asyncio.exceptions.CancelledError

The first message is sent successfully. So the parameters. However, as soon as the server tries to do requestStream.MoveNext(), it throws this error.

I already tried numerous of different solutions, but I cannot find anything that works. Does anyone see where I am making an error?

Turns out, to stream a file, it must be base64 encoded first. That was the whole issue after all.