public void WriteHeadersFrame(HeadersList headers, bool isEndStream)
{
Headers = headers;
byte[] headerBytes = _compressionProc.Compress(headers);
var frame = new HeadersFrame(_id, headerBytes, Priority)
{
IsEndHeaders = true,
IsEndStream = isEndStream,
};
if (frame.IsEndStream)
{
EndStreamSent = true;
}
_writeQueue.WriteFrame(frame);
if (OnFrameSent != null)
{
OnFrameSent(this, new FrameSentArgs(frame));
}
}
public void PumpToStream(CancellationToken cancel)
{
if (cancel == null)
{
throw new ArgumentNullException("cancellation token is null");
}
while (!_disposed)
{
if (cancel.IsCancellationRequested)
{
cancel.ThrowIfCancellationRequested();
}
// send one at a time
lock (_writeLock)
{
if (_messageQueue.Count > 0)
{
var entry = _messageQueue.Dequeue();
/* see https://github.com/MSOpenTech/http2-katana/issues/55
* It's critically important to keep compression context before sending
* headers frame. Since that we are unable to construct headers frame with
* compressed headers block as part of the frame's Buffer, because Queue has
* prioritization mechanism and we must compress headers list immediately before
* sending it. */
if (IsPriorityTurnedOn && entry.Frame is IHeadersFrame && entry.Frame is IPaddingFrame)
{
/* There are two frame types bears Headers Block Fragment: HEADERS and PUSH_PROMISE
* and CONTINUATION, which implements IHeadersFrame interface. It can include additional
* padding as well. Since that we call to interface methods to avoid code redundant. */
// frame reconstruction: headers compression
var headers = (entry.Frame as IHeadersFrame).Headers;
var compressedHeaders = _proc.Compress(headers);
entry.Frame.PayloadLength += compressedHeaders.Length;
// frame reconstruction: add padding
var paddingFrame = entry.Frame as IPaddingFrame;
byte[] padding = new byte[paddingFrame.PadHigh * 256 + paddingFrame.PadLow];
entry.Frame.PayloadLength += padding.Length;
if (entry.Frame is HeadersFrame)
{
var headersFrame = entry.Frame as HeadersFrame;
Http2Logger.LogDebug("Sending HEADERS frame: stream id={0}, payload len={1}, " +
"has pad={2}, pad high={3}, pad low={4}, end stream={5}, " +
"has priority={6}, exclusive={7}, dependency={8}, weight={9}",
headersFrame.StreamId, headersFrame.PayloadLength, headersFrame.HasPadding,
headersFrame.PadHigh, headersFrame.PadLow, headersFrame.IsEndStream,
headersFrame.HasPriority, headersFrame.Exclusive, headersFrame.StreamDependency,
headersFrame.Weight);
}
if (entry.Frame is PushPromiseFrame)
{
var pushPromiseFrame = entry.Frame as PushPromiseFrame;
Http2Logger.LogDebug("Sending PUSH_PROMISE frame: stream id={0}, payload len={1}, " +
"promised id={2}, has pad={3}, pad high={4}, pad low={5}, end headers={6}",
pushPromiseFrame.StreamId, pushPromiseFrame.PayloadLength,
pushPromiseFrame.PromisedStreamId, pushPromiseFrame.HasPadding,
pushPromiseFrame.PadHigh, pushPromiseFrame.PadLow, pushPromiseFrame.IsEndHeaders);
}
if (entry.Frame is ContinuationFrame)
{
var contFrame = entry.Frame as ContinuationFrame;
Http2Logger.LogDebug("Sending CONTINUATION frame: stream id={0}, payload len={1}, has pad={2}, " +
"pad high={3}, pad low={4}, end headers={5}", contFrame.StreamId,
contFrame.PayloadLength, contFrame.HasPadding, contFrame.PadHigh, contFrame.PadLow,
contFrame.IsEndHeaders);
}
// write frame preamble
_stream.Write(entry.Buffer, 0, entry.Buffer.Length);
// write compressed Headers Block
_stream.Write(compressedHeaders, 0, compressedHeaders.Length);
// write frame padding
_stream.Write(padding, 0, padding.Length);
}
else
{
_stream.Write(entry.Buffer, 0, entry.Buffer.Length);
}
}
else
{
Thread.Sleep(10);
}
}
_stream.Flush();
}
}