System.InvalidOperationException ("Concurrent reads or writes are not supported.")

[Xhanti]

Hi,

When trying to use the IConnectionFactory in parallel like this:

var serviceCollection = new ServiceCollection();
var serviceProvider = serviceCollection.BuildServiceProvider();
var client = new ClientBuilder(serviceProvider)
                       .UseSockets()                           
                       .Build();
await using (var connection = await client.ConnectAsync(new IPEndPoint(IPAddress.Loopback, 5000)))
{
    await Parallel.ForAsync(0, 10, options, async (i, ct) =>
    {
        var request = new HttpRequestMessage(HttpMethod.Get, "/");
        request.Headers.Host = "localhost";
        var httpProtocol = new HttpClientProtocol(connection);
        var response = await httpProtocol.SendAsync(request);
    });
}

I get System.InvalidOperationException saying "Concurrent reads or writes are not supported." Digging around I see this is inside system.io.pipelines:

   at Bedrock.Framework.Protocols.HttpClientProtocol.<SendAsync>d__4.MoveNext()
   at Bedrock.Framework.Protocols.HttpClientProtocol.<SendAsync>d__4.MoveNext()
   at Bedrock.Framework.Protocols.HttpClientProtocol.<SendAsync>d__4.MoveNext()
   at System.IO.Pipelines.Pipe.GetReadResult(ReadResult& result) in System.IO.Pipelines\Pipe.cs:line 901
   at System.IO.Pipelines.Pipe.GetReadAsyncResult() in System.IO.Pipelines\Pipe.cs:line 885
   at System.Threading.Tasks.ValueTask`1.get_Result()
   at System.Runtime.CompilerServices.ValueTaskAwaiter`1.GetResult()
   at Bedrock.Framework.Protocols.ProtocolReader.<ContinueDoAsyncRead>d__14`1.MoveNext()
   at System.Runtime.CompilerServices.ValueTaskAwaiter`1.GetResult()
   at System.Runtime.CompilerServices.ValueTaskAwaiter`1.GetResult()
   at Program.<>c__DisplayClass0_0.<<<Main>$>b__0>d.MoveNext() in C:\Working\Raikiri\Raikiri\Program.cs:line 41
   at Bedrock.Framework.Protocols.HttpClientProtocol.<SendAsync>d__4.MoveNext()
   at System.Threading.Tasks.ValueTask`1.get_Result()
   at System.Runtime.CompilerServices.ConfiguredValueTaskAwaitable`1.ConfiguredValueTaskAwaiter.GetResult()
--- End of stack trace from previous location ---
   at Bedrock.Framework.Protocols.HttpClientProtocol.<SendAsync>d__4.MoveNext()
   at System.Threading.Tasks.Parallel.<>c__49`1.<<ForAsync>b__49_0>d.MoveNext()
   at System.Threading.Tasks.Parallel.<>c__49`1.<<ForAsync>b__49_0>d.MoveNext()

Is this expected behavior? For a bit of colour, I'm experimenting with using this framework to put something like https://github.com/codesenberg/bombardier together in .NET

[davidfowl]

Yes, its expected. A real http client needs to implement a connection pool to make sure there are no concurrent writes to the same socket.