Issue with ProtocolReader.ReadAsync and CancellationTokens

I’m writing a server that uses a heartbeat packet. After 10s of inactivity on the socket, the server sends a PING to the client. If using a ProtocolReader, when the PONG comes in, an exception is thrown.

while (true) {
    try
    {
        //Wait for a packet
        ProtocolReadResult<ReadOnlyMemory<byte>> result = await     
           protocolReader.ReadAsync(authProtocol, new CancellationTokenSource(10000).Token);

        //Check for FIN
        if (result.IsCompleted || result.IsCanceled)
            return;

        protocolReader.Advance();    
    }
    catch (OperationCanceledException exception) 
    {
        SendPing(connection);
    }
}

System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values. (Parameter 'startIndex')
   at System.ThrowHelper.ThrowArgumentValidationException[T](ReadOnlySequenceSegment`1 startSegment, Int32 startIndex, ReadOnlySequenceSegment`1 endSegment)
   at System.Buffers.ReadOnlySequence`1..ctor(ReadOnlySequenceSegment`1 startSegment, Int32 startIndex, ReadOnlySequenceSegment`1 endSegment, Int32 endIndex)
   at System.IO.Pipelines.StreamPipeReader.GetCurrentReadOnlySequence()
   at System.IO.Pipelines.StreamPipeReader.ReadAsync(CancellationToken cancellationToken)
   at Bedrock.Framework.Protocols.ProtocolReader.ContinueDoAsyncRead[TReadMessage](ValueTask`1 readTask, Nullable`1 maximumMessageSize, IMessageReader`1 reader, CancellationToken cancellationToken)
   at Auth.AuthHandler.OnConnectedAsync(ConnectionContext connection) in C:\Users\redacted\AuthHandler.cs:line 44

Line 44 is the protocolReader.ReadAsync instruction exactly as shown above. For testing, I tried sending the PING outside of the exception handler, and was able to receive the PONG with no issues. It seems to be related to the operation cancellation. Also, if I replace the protocol reader with a standard pipe reader, this issue does not occur.

[Aenge]

Thanks for the fast response. Our cancellations are working as expected now. 👍

[davidfowl]

Thanks for using the library!