Class HttpServerCodec.HttpServerRequestDecoder

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.handler.codec.ByteToMessageDecoder

io.netty.handler.codec.http.HttpObjectDecoder

io.netty.handler.codec.http.HttpRequestDecoder

io.netty.handler.codec.http.HttpServerCodec.HttpServerRequestDecoder

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler

Enclosing class:

HttpServerCodec

private final class HttpServerCodec.HttpServerRequestDecoder
extends HttpRequestDecoder

Nested Class Summary

Nested classes/interfaces inherited from class ByteToMessageDecoder

ByteToMessageDecoder.Cumulator

Nested classes/interfaces inherited from interface ChannelHandler

ChannelHandler.Sharable

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	discard

Fields inherited from class HttpObjectDecoder

DEFAULT_ALLOW_DUPLICATE_CONTENT_LENGTHS, DEFAULT_ALLOW_PARTIAL_CHUNKS, DEFAULT_CHUNKED_SUPPORTED, DEFAULT_INITIAL_BUFFER_SIZE, DEFAULT_MAX_CHUNK_SIZE, DEFAULT_MAX_HEADER_SIZE, DEFAULT_MAX_INITIAL_LINE_LENGTH, DEFAULT_STRICT_LINE_PARSING, DEFAULT_VALIDATE_HEADERS, headersFactory, PROP_RFC9112_TRANSFER_ENCODING, RFC9112_TRANSFER_ENCODING, trailersFactory, validateHeaders

Fields inherited from class ByteToMessageDecoder

COMPOSITE_CUMULATOR, MERGE_CUMULATOR

Constructor Summary

Constructors

Constructor	Description
HttpServerRequestDecoder(HttpDecoderConfig config)

Method Summary

Modifier and Type	Method	Description
protected void	decode(ChannelHandlerContext ctx, ByteBuf buffer, List<Object> out)	Decode the from one ByteBuf to an other.
protected void	handleTransferEncodingChunkedWithContentLength(HttpMessage message)	Invoked when a message with both a "Transfer-Encoding: chunked" and a "Content-Length" header field is detected.

Methods inherited from class HttpRequestDecoder

createInvalidMessage, createMessage, isContentAlwaysEmpty, isDecodingRequest, splitFirstWordInitialLine, splitHeaderName, splitThirdWordInitialLine

Methods inherited from class HttpObjectDecoder

clearContentLength, decodeLast, handlerRemoved0, isSwitchingToNonHttp1Protocol, isValidating, reset, splitSecondWordInitialLine, userEventTriggered

Methods inherited from class ByteToMessageDecoder

actualReadableBytes, callDecode, channelInactive, channelRead, channelReadComplete, discardSomeReadBytes, handlerRemoved, internalBuffer, isSingleDecode, setCumulator, setDiscardAfterReads, setSingleDecode

Methods inherited from class ChannelInboundHandlerAdapter

channelActive, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught

Methods inherited from class ChannelHandlerAdapter

ensureNotSharable, handlerAdded, isSharable

Methods inherited from class Object

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

Methods inherited from interface ChannelHandler

handlerAdded

Field Details

discard

private boolean discard

Constructor Details

HttpServerRequestDecoder

HttpServerRequestDecoder(HttpDecoderConfig config)

Method Details

decode

protected void decode(ChannelHandlerContext ctx,
 ByteBuf buffer,
 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.

Overrides:

decode in class HttpObjectDecoder

Parameters:

ctx - the ChannelHandlerContext which this ByteToMessageDecoder belongs to

buffer - 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

handleTransferEncodingChunkedWithContentLength

protected void handleTransferEncodingChunkedWithContentLength(HttpMessage message)

Description copied from class: HttpObjectDecoder

Invoked when a message with both a "Transfer-Encoding: chunked" and a "Content-Length" header field is detected. The default behavior is to throw a ContentLengthNotAllowedException exception, but this method could be overridden to change the behavior (to, e.g., remove the Content-Length header value.

See: RFC 9112, Section 6.1-15.

    A server MAY reject a request that contains both Content-Length and Transfer-Encoding
    or process such a request in accordance with the Transfer-Encoding alone.
    Regardless, the server MUST close the connection after responding to such a request
    to avoid the potential attacks.

Since Netty itself cannot track the request/response pairing, it cannot guarantee that the connection is closed immediately after the response is sent. As such, it is safer to immediately reject the request.

Note: RFC 7230 (the previous HTTP/1.1 RFC) allowed the Content-Length header to simply be ignored, in the presence of a Transfer-Encoding header, but this practice is now obsolete and considered unsafe. The RFC 7230 behavior can be restored in the following ways:

• Process-wide, by setting the "io.netty.handler.codec.http.rfc9112TransferEncoding" system property to false.
• Configured for a specific decoder, by setting HttpDecoderConfig.setUseRfc9112TransferEncoding(boolean) to false.
• Hard-coded for a specific decoder, by overriding this method with an implementation like the following:

  @Override
  protected void handleTransferEncodingChunkedWithContentLength(HttpMessage message) {
      clearContentLength();
      message.headers().remove(HttpHeaderNames.CONTENT_LENGTH);
  }
          

Note: This method is only called for HTTP/1.1 requests. Under the default configuration, earlier HTTP protocol versions carrying a Transfer-Encoding header are rejected before reaching this point. However, if HttpDecoderConfig.setUseRfc9112TransferEncoding(boolean) is set to false (see above), that rejection does not happen — a non-HTTP/1.1 message can then legitimately carry Transfer-Encoding without being rejected for it, though this method specifically remains HTTP/1.1-only and is not invoked for such messages.

Overrides:

handleTransferEncodingChunkedWithContentLength in class HttpObjectDecoder