Http3ControlStreamInboundHandler Class — netty Architecture

Source Code

codec-http3/src/main/java/io/netty/handler/codec/http3/Http3ControlStreamInboundHandler.java lines 45–321

final class Http3ControlStreamInboundHandler extends Http3FrameTypeInboundValidationHandler<Http3ControlStreamFrame> {
    final boolean server;
    private final ChannelHandler controlFrameHandler;
    private final QpackEncoder qpackEncoder;
    private final Http3ControlStreamOutboundHandler remoteControlStreamHandler;
    private boolean firstFrameRead;
    private Long receivedGoawayId;
    private Long receivedMaxPushId;

    Http3ControlStreamInboundHandler(boolean server, @Nullable ChannelHandler controlFrameHandler,
                                     QpackEncoder qpackEncoder,
                                     Http3ControlStreamOutboundHandler remoteControlStreamHandler) {
        super(Http3ControlStreamFrame.class);
        this.server = server;
        this.controlFrameHandler = controlFrameHandler;
        this.qpackEncoder = qpackEncoder;
        this.remoteControlStreamHandler = remoteControlStreamHandler;
    }

    boolean isServer() {
        return server;
    }

    boolean isGoAwayReceived() {
        return receivedGoawayId != null;
    }

    long maxPushIdReceived() {
        return receivedMaxPushId == null ? -1 : receivedMaxPushId;
    }

    private boolean forwardControlFrames() {
        return controlFrameHandler != null;
    }

    @Override
    public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
        super.handlerAdded(ctx);
        // The user want's to be notified about control frames, add the handler to the pipeline.
        if (controlFrameHandler != null) {
            ctx.pipeline().addLast(controlFrameHandler);
        }
    }

    @Override
    void readFrameDiscarded(ChannelHandlerContext ctx, Object discardedFrame) {
        if (!firstFrameRead && !(discardedFrame instanceof Http3SettingsFrame)) {
            connectionError(ctx, Http3ErrorCode.H3_MISSING_SETTINGS, "Missing settings frame.", forwardControlFrames());
        }
    }

    @Override
    void channelRead(ChannelHandlerContext ctx, Http3ControlStreamFrame frame) throws QpackException {
        boolean isSettingsFrame = frame instanceof Http3SettingsFrame;
        if (!firstFrameRead && !isSettingsFrame) {
            connectionError(ctx, H3_MISSING_SETTINGS, "Missing settings frame.", forwardControlFrames());
            ReferenceCountUtil.release(frame);
            return;
        }
        if (firstFrameRead && isSettingsFrame) {
            connectionError(ctx, H3_FRAME_UNEXPECTED, "Second settings frame received.", forwardControlFrames());
            ReferenceCountUtil.release(frame);
            return;
        }
        firstFrameRead = true;

        final boolean valid;
        if (isSettingsFrame) {
            valid = handleHttp3SettingsFrame(ctx, (Http3SettingsFrame) frame);
        } else if (frame instanceof Http3GoAwayFrame) {
            valid = handleHttp3GoAwayFrame(ctx, (Http3GoAwayFrame) frame);
        } else if (frame instanceof Http3MaxPushIdFrame) {
            valid = handleHttp3MaxPushIdFrame(ctx, (Http3MaxPushIdFrame) frame);
        } else if (frame instanceof Http3CancelPushFrame) {
            valid = handleHttp3CancelPushFrame(ctx, (Http3CancelPushFrame) frame);
        } else {
            // We don't need to do any special handling for Http3UnknownFrames as we either pass these to the next#
            // handler or release these directly.
            assert frame instanceof Http3UnknownFrame;
            valid = true;
        }