Class HAProxyMessageDecoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.handler.codec.ByteToMessageDecoder

io.netty.handler.codec.haproxy.HAProxyMessageDecoder

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler

public class HAProxyMessageDecoder
extends ByteToMessageDecoder

Decodes an HAProxy proxy protocol header

See Also:

• Proxy Protocol Specification

Nested Class Summary

Nested classes/interfaces inherited from class ByteToMessageDecoder

ByteToMessageDecoder.Cumulator

Modifier and Type	Class	Description
static interface	ByteToMessageDecoder.Cumulator	Cumulate ByteBufs.

Nested classes/interfaces inherited from interface ChannelHandler

ChannelHandler.Sharable

Modifier and Type	Interface	Description
static @interface	ChannelHandler.Sharable	Indicates that the same instance of the annotated ChannelHandler can be added to one or more ChannelPipelines multiple times without a race condition.

Field Summary

Fields inherited from class ByteToMessageDecoder

COMPOSITE_CUMULATOR, MERGE_CUMULATOR

Modifier and Type	Field	Description
static final ByteToMessageDecoder.Cumulator	COMPOSITE_CUMULATOR	Cumulate ByteBufs by add them to a CompositeByteBuf and so do no memory copy whenever possible.
static final ByteToMessageDecoder.Cumulator	MERGE_CUMULATOR	Cumulate ByteBufs by merge them into one ByteBuf's, using memory copies.

Constructor Summary

Constructors

Constructor	Description
HAProxyMessageDecoder()	Creates a new decoder with no additional data (TLV) restrictions, and should throw an exception as soon as we exceed maxLength.
HAProxyMessageDecoder(boolean failFast)	Creates a new decoder with no additional data (TLV) restrictions, whether or not to throw an exception as soon as we exceed maxLength.
HAProxyMessageDecoder(int maxTlvSize)	Creates a new decoder with restricted additional data (TLV) size, and should throw an exception as soon as we exceed maxLength.
HAProxyMessageDecoder(int maxTlvSize, boolean failFast)	Creates a new decoder with restricted additional data (TLV) size, whether or not to throw an exception as soon as we exceed maxLength.

Method Summary

Modifier and Type	Method	Description
void	channelRead(ChannelHandlerContext ctx, Object msg)	Calls ChannelHandlerContext.fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline.
protected final void	decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out)	Decode the from one ByteBuf to an other.
static ProtocolDetectionResult<HAProxyProtocolVersion>	detectProtocol(ByteBuf buffer)	Returns the ProtocolDetectionResult for the given ByteBuf.
boolean	isSingleDecode()	If true then only one message is decoded on each ByteToMessageDecoder.channelRead(ChannelHandlerContext, Object) call.

Methods inherited from class ByteToMessageDecoder

actualReadableBytes, callDecode, channelInactive, channelReadComplete, decodeLast, discardSomeReadBytes, handlerRemoved, handlerRemoved0, internalBuffer, setCumulator, setDiscardAfterReads, setSingleDecode, userEventTriggered

Modifier and Type	Method	Description
protected int	actualReadableBytes()	Returns the actual number of readable bytes in the internal cumulative buffer of this decoder.
protected void	callDecode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out)	Called once data should be decoded from the given ByteBuf.
void	channelInactive(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelInactive() 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 void	decodeLast(ChannelHandlerContext ctx, ByteBuf in, List<Object> out)	Is called one last time when the ChannelHandlerContext goes in-active.
protected final void	discardSomeReadBytes()
final void	handlerRemoved(ChannelHandlerContext ctx)	Do nothing by default, sub-classes may override this method.
protected void	handlerRemoved0(ChannelHandlerContext ctx)	Gets called after the ByteToMessageDecoder was removed from the actual context and it doesn't handle events anymore.
protected ByteBuf	internalBuffer()	Returns the internal cumulative buffer of this decoder.
void	setCumulator(ByteToMessageDecoder.Cumulator cumulator)	Set the ByteToMessageDecoder.Cumulator to use for cumulate the received ByteBufs.
void	setDiscardAfterReads(int discardAfterReads)	Set the number of reads after which ByteBuf.discardSomeReadBytes() are called and so free up memory.
void	setSingleDecode(boolean singleDecode)	If set then only one message is decoded on each ByteToMessageDecoder.channelRead(ChannelHandlerContext, Object) call.
void	userEventTriggered(ChannelHandlerContext ctx, Object evt)	Calls ChannelHandlerContext.fireUserEventTriggered(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline.

Methods inherited from class ChannelInboundHandlerAdapter

channelActive, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught

Modifier and Type	Method	Description
void	channelActive(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelActive() to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	channelRegistered(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelRegistered() to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	channelUnregistered(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelUnregistered() to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	channelWritabilityChanged(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelWritabilityChanged() to forward to the next ChannelInboundHandler in the ChannelPipeline.
void	exceptionCaught(ChannelHandlerContext ctx, Throwable cause)	Calls ChannelHandlerContext.fireExceptionCaught(Throwable) to forward to the next ChannelHandler in the ChannelPipeline.

Methods inherited from class ChannelHandlerAdapter

ensureNotSharable, handlerAdded, isSharable

Modifier and Type	Method	Description
protected void	ensureNotSharable()	Throws IllegalStateException if ChannelHandlerAdapter.isSharable() returns true
void	handlerAdded(ChannelHandlerContext ctx)	Do nothing by default, sub-classes may override this method.
boolean	isSharable()	Return true if the implementation is ChannelHandler.Sharable and so can be added to different ChannelPipelines.

Methods inherited from class Object

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

Constructor Details

HAProxyMessageDecoder

public HAProxyMessageDecoder()

Creates a new decoder with no additional data (TLV) restrictions, and should throw an exception as soon as we exceed maxLength.

HAProxyMessageDecoder

public HAProxyMessageDecoder(boolean failFast)

Creates a new decoder with no additional data (TLV) restrictions, whether or not to throw an exception as soon as we exceed maxLength.

Parameters:

failFast - Whether or not to throw an exception as soon as we exceed maxLength

HAProxyMessageDecoder

public HAProxyMessageDecoder(int maxTlvSize)

Creates a new decoder with restricted additional data (TLV) size, and should throw an exception as soon as we exceed maxLength.

Note: limiting TLV size only affects processing of v2, binary headers. Also, as allowed by the 1.5 spec TLV data is currently ignored. For maximum performance it would be best to configure your upstream proxy host to NOT send TLV data and instantiate with a max TLV size of 0.

Parameters:

maxTlvSize - maximum number of bytes allowed for additional data (Type-Length-Value vectors) in a v2 header

HAProxyMessageDecoder

public HAProxyMessageDecoder(int maxTlvSize,
 boolean failFast)

Creates a new decoder with restricted additional data (TLV) size, whether or not to throw an exception as soon as we exceed maxLength.

Parameters:

maxTlvSize - maximum number of bytes allowed for additional data (Type-Length-Value vectors) in a v2 header

failFast - Whether or not to throw an exception as soon as we exceed maxLength

Method Details

isSingleDecode

public boolean isSingleDecode()

Description copied from class: ByteToMessageDecoder

If true then only one message is decoded on each ByteToMessageDecoder.channelRead(ChannelHandlerContext, Object) call. Default is false as this has performance impacts.

Overrides:

isSingleDecode in class ByteToMessageDecoder

channelRead

public void channelRead(ChannelHandlerContext ctx,
 Object msg)
                 throws 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 ByteToMessageDecoder

Throws:

Exception

decode

protected final void decode(ChannelHandlerContext ctx,
 ByteBuf in,
 List<Object> out)
                     throws Exception

Description copied from class: ByteToMessageDecoder

Decode the from one ByteBuf to an other. This method will be called till either the input ByteBuf has nothing to read when return from this method or till nothing was read from the input ByteBuf.

Specified by:

decode in class ByteToMessageDecoder

Parameters:

ctx - the ChannelHandlerContext which this ByteToMessageDecoder belongs to

in - the ByteBuf from which to read data

out - the List to which decoded messages should be added

Throws:

Exception - is thrown if an error occurs

detectProtocol

public static ProtocolDetectionResult<HAProxyProtocolVersion> detectProtocol(ByteBuf buffer)

Returns the ProtocolDetectionResult for the given ByteBuf.