Package io.netty.handler.codec.quic

Class QuicCodecDispatcher

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.handler.codec.quic.QuicCodecDispatcher

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler

public abstract class QuicCodecDispatcher
extends ChannelInboundHandlerAdapter

Special ChannelHandler that should be used to init Channels that will be used for QUIC while SO_REUSEPORT is used to bind to same InetSocketAddress multiple times. This is necessary to ensure QUIC packets are always dispatched to the correct codec that keeps the mapping for the connection id. This implementation use a very simple mapping strategy by encoding the index of the internal datastructure that keeps track of the different ChannelHandlerContexts into the destination connection id. This way once a QUIC packet is received its possible to forward it to the right codec. Subclasses might change how encoding / decoding of the index is done by overriding decodeIndex(ByteBuf) and newIdGenerator(int).

It is important that the same QuicCodecDispatcher instance is shared between all the Channels that are bound to the same InetSocketAddress and use SO_REUSEPORT.

An alternative way to handle this would be to do the "routing" to the correct socket in an epbf program by implementing your own QuicConnectionIdGenerator that issue ids that can be understood and handled by the epbf program to route the packet to the correct socket.

Nested Class Summary

Nested classes/interfaces inherited from interface io.netty.channel.ChannelHandler

ChannelHandler.Sharable

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	QuicCodecDispatcher()	Create a new instance using the default connection id length.
protected	QuicCodecDispatcher(int localConnectionIdLength)	Create a new instance

Method Summary

Modifier and Type	Method	Description
void	channelRead(ChannelHandlerContext ctx, java.lang.Object msg)	Calls ChannelHandlerContext.fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	channelReadComplete(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelReadComplete() to forward to the next ChannelInboundHandler in the ChannelPipeline.
protected int	decodeIndex(ByteBuf connectionId)	Return the idx that was encoded into the connectionId via the QuicConnectionIdGenerator before, or -1 if decoding was not successful.
void	handlerAdded(ChannelHandlerContext ctx)	Do nothing by default, sub-classes may override this method.
void	handlerRemoved(ChannelHandlerContext ctx)	Do nothing by default, sub-classes may override this method.
protected abstract void	initChannel(Channel channel, int localConnectionIdLength, QuicConnectionIdGenerator idGenerator)	Init the Channel and add all the needed ChannelHandler to the pipeline.
boolean	isSharable()	Return true if the implementation is ChannelHandler.Sharable and so can be added to different ChannelPipelines.
protected QuicConnectionIdGenerator	newIdGenerator(int idx)	Returns a QuicConnectionIdGenerator that will encode the given index into all the ids that it produces.

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

channelActive, channelInactive, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught, userEventTriggered

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

QuicCodecDispatcher

protected QuicCodecDispatcher()

Create a new instance using the default connection id length.

QuicCodecDispatcher

protected QuicCodecDispatcher(int localConnectionIdLength)

Create a new instance

Parameters:

localConnectionIdLength - the local connection id length. This must be between 10 and 20.

Method Detail

isSharable

public final boolean isSharable()

Description copied from class: ChannelHandlerAdapter

Return true if the implementation is ChannelHandler.Sharable and so can be added to different ChannelPipelines.

Overrides:

isSharable in class ChannelHandlerAdapter

handlerAdded

public final void handlerAdded(ChannelHandlerContext ctx)
                        throws java.lang.Exception

Description copied from class: ChannelHandlerAdapter

Do nothing by default, sub-classes may override this method.

Specified by:

handlerAdded in interface ChannelHandler

Overrides:

handlerAdded in class ChannelHandlerAdapter

Throws:

java.lang.Exception

handlerRemoved

public final void handlerRemoved(ChannelHandlerContext ctx)
                          throws java.lang.Exception

Description copied from class: ChannelHandlerAdapter

Do nothing by default, sub-classes may override this method.

Specified by:

handlerRemoved in interface ChannelHandler

Overrides:

handlerRemoved in class ChannelHandlerAdapter

Throws:

java.lang.Exception

channelRead

public final void channelRead(ChannelHandlerContext ctx,
                              java.lang.Object msg)
                       throws java.lang.Exception

Description copied from class: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

channelRead in interface ChannelInboundHandler

Overrides:

channelRead in class ChannelInboundHandlerAdapter

Throws:

java.lang.Exception

channelReadComplete

public final void channelReadComplete(ChannelHandlerContext ctx)

Description copied from class: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireChannelReadComplete() to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

channelReadComplete in interface ChannelInboundHandler

Overrides:

channelReadComplete in class ChannelInboundHandlerAdapter

initChannel

protected abstract void initChannel(Channel channel,
                                    int localConnectionIdLength,
                                    QuicConnectionIdGenerator idGenerator)
                             throws java.lang.Exception

Init the Channel and add all the needed ChannelHandler to the pipeline. This also included building the QUIC codec via QuicCodecBuilder sub-type using the given local connection id length and QuicConnectionIdGenerator.

Parameters:

channel - the Channel to init.

localConnectionIdLength - the local connection id length that must be used with the QuicCodecBuilder.

idGenerator - the QuicConnectionIdGenerator that must be used with the QuicCodecBuilder.

Throws:

java.lang.Exception - thrown on error.

decodeIndex

protected int decodeIndex(ByteBuf connectionId)

Return the idx that was encoded into the connectionId via the QuicConnectionIdGenerator before, or -1 if decoding was not successful.

Subclasses may override this. In this case newIdGenerator(int) should be overridden as well to implement the encoding scheme for the encoding side.

Parameters:

connectionId - the destination connection id of the QUIC connection.

Returns:

the index or -1.

newIdGenerator

protected QuicConnectionIdGenerator newIdGenerator(int idx)

Returns a QuicConnectionIdGenerator that will encode the given index into all the ids that it produces.

Subclasses may override this. In this case decodeIndex(ByteBuf) should be overridden as well to implement the encoding scheme for the decoding side.

Parameters:

idx - the index to encode into each id.

Returns:

the QuicConnectionIdGenerator.