/// <summary>Sends a <see cref="SPDYFrame"/> on the network.</summary>
/// <exception cref="InvalidOperationException">Thrown if the connection was closed (<see cref="IsOpen"/> is false) or if the
/// connection becomes closed while sending the frame
/// </exception>
/// <remarks>Only one thread is allowed to be sending frames at a time. If the <paramref name="cancelToken"/> is canceled in the
/// middle of sending the frame, the connection may be closed.
/// </remarks>
public async Task SendFrameAsync(SPDYFrame frame, CancellationToken cancelToken = default)
{
if (!frame.IsValid)
{
throw new ArgumentException("The frame is not valid.");
}
AssertOpen();
cancelToken.ThrowIfCancellationRequested();
frame.CopyHeaderTo(writeBuffer); // get the header bytes
try
{
await writeStream.WriteAsync(writeBuffer, 0, SPDYFrame.HeaderSize, cancelToken).ConfigureAwait(false); // send the header
await writeStream.WriteAsync(frame.Data, 0, frame.DataLength, cancelToken).ConfigureAwait(false); // and then the data
}
catch (Exception ex) // if an exception occurred, we don't know if the state of the stream has been corrupted
{
CloseCore(); // so stay on the safe side and close the connection
if (ex is ObjectDisposedException || ex is IOException || ex is System.Net.Sockets.SocketException) // if the connection was closed...
{
throw new InvalidOperationException("The connection was closed.", ex); // normalize to a known exception
}
throw; // for other exceptions (e.g. cancellation), rethrow
}
}
