public void updateWindow() throws Http2Exception {
  if (!autoTuneFlowControlOn) {
    return;
  }
  pingReturn++;
  long elapsedTime = (System.nanoTime() - lastPingTime);
  if (elapsedTime == 0) {
    elapsedTime = 1;
  }
  long bandwidth = (getDataSincePing() * TimeUnit.SECONDS.toNanos(1)) / elapsedTime;
  Http2LocalFlowController fc = decoder().flowController();
  // Calculate new window size by doubling the observed BDP, but cap at max window
  int targetWindow = Math.min(getDataSincePing() * 2, MAX_WINDOW_SIZE);
  setPinging(false);
  int currentWindow = fc.initialWindowSize(connection().connectionStream());
  if (targetWindow > currentWindow && bandwidth > lastBandwidth) {
    lastBandwidth = bandwidth;
    int increase = targetWindow - currentWindow;
    fc.incrementWindowSize(connection().connectionStream(), increase);
    fc.initialWindowSize(targetWindow);
    Http2Settings settings = new Http2Settings();
    settings.initialWindowSize(targetWindow);
    frameWriter().writeSettings(ctx(), settings, ctx().newPromise());
  }
}
 

public void updateWindow() throws Http2Exception {
  if (!autoTuneFlowControlOn) {
    return;
  }
  pingReturn++;
  long elapsedTime = (System.nanoTime() - lastPingTime);
  if (elapsedTime == 0) {
    elapsedTime = 1;
  }
  long bandwidth = (getDataSincePing() * TimeUnit.SECONDS.toNanos(1)) / elapsedTime;
  Http2LocalFlowController fc = decoder().flowController();
  // Calculate new window size by doubling the observed BDP, but cap at max window
  int targetWindow = Math.min(getDataSincePing() * 2, MAX_WINDOW_SIZE);
  setPinging(false);
  int currentWindow = fc.initialWindowSize(connection().connectionStream());
  if (targetWindow > currentWindow && bandwidth > lastBandwidth) {
    lastBandwidth = bandwidth;
    int increase = targetWindow - currentWindow;
    fc.incrementWindowSize(connection().connectionStream(), increase);
    fc.initialWindowSize(targetWindow);
    Http2Settings settings = new Http2Settings();
    settings.initialWindowSize(targetWindow);
    frameWriter().writeSettings(ctx(), settings, ctx().newPromise());
  }

}
 

@Override
protected void manualSetUp() throws Exception {
  assertNull("manualSetUp should not run more than once", handler());

  initChannel(new GrpcHttp2ServerHeadersDecoder(GrpcUtil.DEFAULT_MAX_HEADER_LIST_SIZE));

  // replace the keepAliveManager with spyKeepAliveManager
  spyKeepAliveManager =
      mock(KeepAliveManager.class, delegatesTo(handler().getKeepAliveManagerForTest()));
  handler().setKeepAliveManagerForTest(spyKeepAliveManager);

  // Simulate receipt of the connection preface
  handler().handleProtocolNegotiationCompleted(Attributes.EMPTY, /*securityInfo=*/ null);
  channelRead(Http2CodecUtil.connectionPrefaceBuf());
  // Simulate receipt of initial remote settings.
  ByteBuf serializedSettings = serializeSettings(new Http2Settings());
  channelRead(serializedSettings);
}
 

private void configureHttp2(ChannelPipeline pipeline) {

        // setup the initial stream settings for the server to use.
        Http2Settings settings = new Http2Settings()
                .maxConcurrentStreams(maxConcurrentStreams)
                .initialWindowSize(initialWindowSize)
                .headerTableSize(maxHeaderTableSize)
                .maxHeaderListSize(maxHeaderListSize);

        Http2FrameCodec frameCodec = Http2FrameCodecBuilder.forServer()
                .frameLogger(FRAME_LOGGER)
                .initialSettings(settings)
                .validateHeaders(true)
                .build();

        Http2MultiplexHandler multiplexHandler = new Http2MultiplexHandler(http2StreamHandler);

        // The frame codec MUST be in the pipeline.
        pipeline.addBefore("codec_placeholder", /* name= */ null, frameCodec);
        pipeline.replace("codec_placeholder", HTTP_CODEC_HANDLER_NAME, multiplexHandler);
    }
 

static void configureHttp2Pipeline(ChannelPipeline p, HttpResponseDecoderSpec decoder, Http2Settings http2Settings,
		ConnectionObserver observer) {
	Http2FrameCodecBuilder http2FrameCodecBuilder =
			Http2FrameCodecBuilder.forClient()
			                      .validateHeaders(decoder.validateHeaders())
			                      .initialSettings(http2Settings);

	if (p.get(NettyPipeline.LoggingHandler) != null) {
		http2FrameCodecBuilder.frameLogger(new Http2FrameLogger(LogLevel.DEBUG,
				"reactor.netty.http.client.h2"));
	}

	p.addBefore(NettyPipeline.ReactiveBridge, NettyPipeline.HttpCodec, http2FrameCodecBuilder.build())
	 .addBefore(NettyPipeline.ReactiveBridge, NettyPipeline.H2MultiplexHandler, new Http2MultiplexHandler(new H2Codec()))
	 .addBefore(NettyPipeline.ReactiveBridge, NettyPipeline.HttpTrafficHandler, new HttpTrafficHandler(observer));
}
 

static void configureH2Pipeline(ChannelPipeline p,
		ServerCookieDecoder cookieDecoder,
		ServerCookieEncoder cookieEncoder,
		boolean forwarded,
		Http2Settings http2Settings,
		ConnectionObserver listener,
		ChannelOperations.OnSetup opsFactory,
		boolean validate) {
	p.remove(NettyPipeline.ReactiveBridge);

	Http2FrameCodecBuilder http2FrameCodecBuilder =
			Http2FrameCodecBuilder.forServer()
			                      .validateHeaders(validate)
			                      .initialSettings(http2Settings);

	if (p.get(NettyPipeline.LoggingHandler) != null) {
		http2FrameCodecBuilder.frameLogger(new Http2FrameLogger(LogLevel.DEBUG,
				"reactor.netty.http.server.h2"));
	}

	p.addLast(NettyPipeline.HttpCodec, http2FrameCodecBuilder.build())
	 .addLast(NettyPipeline.H2MultiplexHandler,
	          new Http2MultiplexHandler(new H2Codec(opsFactory, listener, forwarded, cookieEncoder, cookieDecoder)));
}
 

Http11OrH2CleartextCodec(
		ServerCookieDecoder cookieDecoder,
		ServerCookieEncoder cookieEncoder,
		boolean debug,
		boolean forwarded,
		Http2Settings http2Settings,
		ConnectionObserver listener,
		ChannelOperations.OnSetup opsFactory,
		boolean validate) {
	this.cookieDecoder = cookieDecoder;
	this.cookieEncoder = cookieEncoder;
	this.forwarded = forwarded;
	Http2FrameCodecBuilder http2FrameCodecBuilder =
			Http2FrameCodecBuilder.forServer()
			                      .validateHeaders(validate)
			                      .initialSettings(http2Settings);

	if (debug) {
		http2FrameCodecBuilder.frameLogger(new Http2FrameLogger(
				LogLevel.DEBUG,
				"reactor.netty.http.server.h2"));
	}
	this.http2FrameCodec = http2FrameCodecBuilder.build();
	this.listener = listener;
	this.opsFactory = opsFactory;
}
 

H2OrHttp11Codec(
		@Nullable BiPredicate<HttpServerRequest, HttpServerResponse> compressPredicate,
		ServerCookieDecoder cookieDecoder,
		ServerCookieEncoder cookieEncoder,
		HttpRequestDecoderSpec decoder,
		boolean forwarded,
		Http2Settings http2Settings,
		ConnectionObserver listener,
		@Nullable Supplier<? extends ChannelMetricsRecorder> metricsRecorder,
		int minCompressionSize,
		ChannelOperations.OnSetup opsFactory,
		@Nullable Function<String, String> uriTagValue) {
	super(ApplicationProtocolNames.HTTP_1_1);
	this.compressPredicate = compressPredicate;
	this.cookieDecoder = cookieDecoder;
	this.cookieEncoder = cookieEncoder;
	this.decoder = decoder;
	this.forwarded = forwarded;
	this.http2Settings = http2Settings;
	this.listener = listener;
	this.metricsRecorder = metricsRecorder;
	this.minCompressionSize = minCompressionSize;
	this.opsFactory = opsFactory;
	this.uriTagValue = uriTagValue;
}
 

@Override
protected void manualSetUp() throws Exception {
  assertNull("manualSetUp should not run more than once", handler());

  initChannel(new GrpcHttp2ServerHeadersDecoder(GrpcUtil.DEFAULT_MAX_HEADER_LIST_SIZE));

  // replace the keepAliveManager with spyKeepAliveManager
  spyKeepAliveManager =
      mock(KeepAliveManager.class, delegatesTo(handler().getKeepAliveManagerForTest()));
  handler().setKeepAliveManagerForTest(spyKeepAliveManager);

  // Simulate receipt of the connection preface
  handler().handleProtocolNegotiationCompleted(Attributes.EMPTY, /*securityInfo=*/ null);
  channelRead(Http2CodecUtil.connectionPrefaceBuf());
  // Simulate receipt of initial remote settings.
  ByteBuf serializedSettings = serializeSettings(new Http2Settings());
  channelRead(serializedSettings);
}
 

private Http2Settings http2Settings() {
    final Http2Settings settings = new Http2Settings();
    final int initialWindowSize = config.http2InitialStreamWindowSize();
    if (initialWindowSize != Http2CodecUtil.DEFAULT_WINDOW_SIZE) {
        settings.initialWindowSize(initialWindowSize);
    }

    final int maxFrameSize = config.http2MaxFrameSize();
    if (maxFrameSize != Http2CodecUtil.DEFAULT_MAX_FRAME_SIZE) {
        settings.maxFrameSize(maxFrameSize);
    }

    // Not using the value greater than 2^31-1 because some HTTP/2 client implementations use a signed
    // 32-bit integer to represent an HTTP/2 SETTINGS parameter value.
    settings.maxConcurrentStreams(Math.min(config.http2MaxStreamsPerConnection(), Integer.MAX_VALUE));
    settings.maxHeaderListSize(config.http2MaxHeaderListSize());
    return settings;
}
 

AbstractNettyHandler(
    ChannelPromise channelUnused,
    Http2ConnectionDecoder decoder,
    Http2ConnectionEncoder encoder,
    Http2Settings initialSettings,
    boolean autoFlowControl) {
  super(channelUnused, decoder, encoder, initialSettings);

  // During a graceful shutdown, wait until all streams are closed.
  gracefulShutdownTimeoutMillis(GRACEFUL_SHUTDOWN_NO_TIMEOUT);

  // Extract the connection window from the settings if it was set.
  this.initialConnectionWindow = initialSettings.initialWindowSize() == null ? -1 :
          initialSettings.initialWindowSize();
  this.autoTuneFlowControlOn = autoFlowControl;
  if (encoder instanceof ListeningEncoder) {
    ((ListeningEncoder) encoder).setListener(pingCountingListener);
  }
}
 

@Override
public void onSettingsRead(ChannelHandlerContext ctx, Http2Settings settings) {
  if (firstSettings) {
    firstSettings = false;
    lifecycleManager.notifyReady();
  }
}
 

@Override
public void onSettingsRead(ChannelHandlerContext ctx, Http2Settings settings) {
  if (firstSettings) {
    firstSettings = false;
    lifecycleManager.notifyReady();
  }
}
 

AbstractNettyHandler(
    ChannelPromise channelUnused,
    Http2ConnectionDecoder decoder,
    Http2ConnectionEncoder encoder,
    Http2Settings initialSettings) {
  super(channelUnused, decoder, encoder, initialSettings);

  // During a graceful shutdown, wait until all streams are closed.
  gracefulShutdownTimeoutMillis(GRACEFUL_SHUTDOWN_NO_TIMEOUT);

  // Extract the connection window from the settings if it was set.
  this.initialConnectionWindow = initialSettings.initialWindowSize() == null ? -1 :
          initialSettings.initialWindowSize();
}
 

@Test
public void transportReadyDelayedUntilConnectionPreface() throws Exception {
  initChannel(new GrpcHttp2ServerHeadersDecoder(GrpcUtil.DEFAULT_MAX_HEADER_LIST_SIZE));

  handler().handleProtocolNegotiationCompleted(Attributes.EMPTY, /*securityInfo=*/ null);
  verify(transportListener, never()).transportReady(any(Attributes.class));

  // Simulate receipt of the connection preface
  channelRead(Http2CodecUtil.connectionPrefaceBuf());
  channelRead(serializeSettings(new Http2Settings()));
  verify(transportListener).transportReady(any(Attributes.class));
}
 

@Test
public void shouldAdvertiseMaxConcurrentStreams() throws Exception {
  maxConcurrentStreams = 314;
  manualSetUp();

  ArgumentCaptor<Http2Settings> captor = ArgumentCaptor.forClass(Http2Settings.class);
  verifyWrite().writeSettings(
      any(ChannelHandlerContext.class), captor.capture(), any(ChannelPromise.class));

  assertEquals(maxConcurrentStreams, captor.getValue().maxConcurrentStreams().intValue());
}
 

@Test
public void shouldAdvertiseMaxHeaderListSize() throws Exception {
  maxHeaderListSize = 123;
  manualSetUp();

  ArgumentCaptor<Http2Settings> captor = ArgumentCaptor.forClass(Http2Settings.class);
  verifyWrite().writeSettings(
      any(ChannelHandlerContext.class), captor.capture(), any(ChannelPromise.class));

  assertEquals(maxHeaderListSize, captor.getValue().maxHeaderListSize().intValue());
}
 

private CapturingGrpcHttp2ConnectionHandler capturingGrpcHandler() {
  // Netty Boilerplate.  We don't really need any of this, but there is a tight coupling
  // between a Http2ConnectionHandler and its dependencies.
  Http2Connection connection = new DefaultHttp2Connection(true);
  Http2FrameWriter frameWriter = new DefaultHttp2FrameWriter();
  Http2FrameReader frameReader = new DefaultHttp2FrameReader(false);
  DefaultHttp2ConnectionEncoder encoder =
      new DefaultHttp2ConnectionEncoder(connection, frameWriter);
  DefaultHttp2ConnectionDecoder decoder =
      new DefaultHttp2ConnectionDecoder(connection, encoder, frameReader);

  return new CapturingGrpcHttp2ConnectionHandler(decoder, encoder, new Http2Settings());
}
 

@Override
protected void channelRead0(ChannelHandlerContext ctx, Http2Settings msg) throws Exception {
    promise.setSuccess();

    // Only care about the first settings message
    ctx.pipeline().remove(this);
}
 

@Override
protected HelloWorldHttp2Handler build(Http2ConnectionDecoder decoder, Http2ConnectionEncoder encoder,
                                       Http2Settings initialSettings) {
    HelloWorldHttp2Handler handler = new HelloWorldHttp2Handler(decoder, encoder, initialSettings);
    frameListener(handler);
    return handler;
}
 

@Override
public void channelCreated(Channel ch) throws Exception {
  ChannelPipeline pipeline = ch.pipeline();
  SslHandler sslHandler = new SslHandler(sslFactory.createSSLEngine(host, port, SSLFactory.Mode.CLIENT));
  pipeline.addLast(sslHandler);
  pipeline.addLast(Http2FrameCodecBuilder.forClient()
      .initialSettings(Http2Settings.defaultSettings()
          .maxFrameSize(http2ClientConfig.http2FrameMaxSize)
          .initialWindowSize(http2ClientConfig.http2InitialWindowSize))
      .frameLogger(new Http2FrameLogger(LogLevel.DEBUG, "client"))
      .build());
  pipeline.addLast(new Http2MultiplexHandler(new ChannelInboundHandlerAdapter()));
}
 

@Override
protected Http2Handler build(Http2ConnectionDecoder decoder, Http2ConnectionEncoder encoder,
                             Http2Settings initialSettings) {
    Http2Handler handler = new Http2Handler(decoder, encoder, initialSettings);
    frameListener(handler);
    return handler;
}
 

@Test
public void shouldAdvertiseMaxConcurrentStreams() throws Exception {
  maxConcurrentStreams = 314;
  manualSetUp();

  ArgumentCaptor<Http2Settings> captor = ArgumentCaptor.forClass(Http2Settings.class);
  verifyWrite().writeSettings(
      any(ChannelHandlerContext.class), captor.capture(), any(ChannelPromise.class));

  assertEquals(maxConcurrentStreams, captor.getValue().maxConcurrentStreams().intValue());
}
 

@Override
protected Http2ServerChannelHandler build(Http2ConnectionDecoder decoder, Http2ConnectionEncoder encoder,
                                          Http2Settings initialSettings) {
    Http2ServerChannelHandler handler = new Http2ServerChannelHandler(serverHandler, decoder, encoder,
        initialSettings);
    frameListener(handler);
    return handler;
}
 

@Override
protected Http2ConnectionHandler build(
    Http2ConnectionDecoder decoder,
    Http2ConnectionEncoder encoder,
    Http2Settings initialSettings) {

  // TODO(jkinkead): Set MAX_CONCURRENT_STREAMS value to something from config.
  decoder.frameListener(new Http2Handler(encoder, maxPayloadBytes, corsHandler));

  return new ConnectionHandler(decoder, encoder, initialSettings);
}
 

@Override
protected void initChannel(SocketChannel ch) {
    Http2FrameCodec codec = Http2FrameCodecBuilder.forServer()
            .autoAckPingFrame(true)
            .initialSettings(new Http2Settings()
                .initialWindowSize(16384)
                .maxFrameSize(16384)
                .maxConcurrentStreams(5))
            .build();

    ch.pipeline().addLast(codec);
    ch.pipeline().addLast(handlerSupplier.get());
}
 

@Override
protected void initChannel(SocketChannel ch) {
    Http2FrameCodec codec = Http2FrameCodecBuilder.forServer()
            .initialSettings(new Http2Settings()
                    .maxConcurrentStreams(5))
            .build();

    ch.pipeline().addLast(codec);
    ch.pipeline().addLast(handlerSupplier.get());
}
 

public static EmbeddedChannel newHttp2Channel(ChannelHandler channelHandler) {
    Http2FrameCodec http2FrameCodec = Http2FrameCodecBuilder.forClient().initialSettings(
        Http2Settings.defaultSettings().initialWindowSize(INITIAL_WINDOW_SIZE))
                                                            .frameLogger(new Http2FrameLogger(LogLevel.DEBUG)).build();
    EmbeddedChannel channel = new EmbeddedChannel(http2FrameCodec,
                                                  new Http2MultiplexHandler(channelHandler));

    channel.attr(ChannelAttributeKey.HTTP2_CONNECTION).set(http2FrameCodec.connection());
    channel.attr(ChannelAttributeKey.HTTP2_INITIAL_WINDOW_SIZE).set(INITIAL_WINDOW_SIZE);
    channel.attr(ChannelAttributeKey.PROTOCOL_FUTURE).set(CompletableFuture.completedFuture(Protocol.HTTP2));
    return channel;
}
 

private Http2SettingsFrame http2SettingsFrame(long serverMaxStreams) {
    return new Http2SettingsFrame() {
        @Override
        public Http2Settings settings() {
            Http2Settings http2Settings = new Http2Settings();
            http2Settings.maxConcurrentStreams(serverMaxStreams);
            return http2Settings;
        }

        @Override
        public String name() {
            return "test";
        }
    };
}
 

FakeGrpcHttp2ConnectionHandler(ChannelPromise channelUnused,
    Http2ConnectionDecoder decoder,
    Http2ConnectionEncoder encoder,
    Http2Settings initialSettings,
    boolean noop) {
  super(channelUnused, decoder, encoder, initialSettings);
  this.noop = noop;
}