Related issue: #2741 and #2151
Motivation:
There is no way for ChunkedWriteHandler to know the progress of the
transfer of a ChannelInput. Therefore, ChannelProgressiveFutureListener
cannot get exact information about the progress of the transfer.
If you add a few methods that optionally provides the transfer progress
to ChannelInput, it becomes possible for ChunkedWriteHandler to notify
ChannelProgressiveFutureListeners.
If the input has no definite length, we can still use the progress so
far, and consider the length of the input as 'undefined'.
Modifications:
- Add ChunkedInput.progress() and ChunkedInput.length()
- Modify ChunkedWriteHandler to use progress() and length() to notify
the transfer progress
Result:
ChunkedWriteHandler now notifies ChannelProgressiveFutureListener.
Motivation:
The _0XFF_0X00 buffer is not duplicated and empty after the first usage preventing the connection close to happen on subsequent close frames.
Modifications:
Correctly duplicate the buffer.
Result:
Multiple CloseWebSocketFrames are handled correctly.
In Netty 3, downstream writes of SPDY data frames and upstream reads of
SPDY window udpate frames occur on different threads.
When receiving a window update frame, we synchronize on a java object
(SpdySessionHandler::flowControlLock) while sending any pending writes
that are now able to complete.
When writing a data frame, we check the send window size to see if we
are allowed to write it to the socket, or if we have to enqueue it as a
pending write. To prevent races with the window update frame, this is
also synchronized on the same SpdySessionHandler::flowControlLock.
In Netty 4, upstream and downstream operations on any given channel now
occur on the same thread. Since java locks are re-entrant, this now
allows downstream writes to occur while processing window update frames.
In particular, when we receive a window update frame that unblocks a
pending write, this write completes which triggers an event notification
on the response, which in turn triggers a write of a data frame. Since
this is on the same thread it re-enters the lock and modifies the send
window. When the write completes, we continue processing pending writes
without knowledge that the window size has been decremented.
Related issue: #2743
Motivation:
When there are more than one stream with the same priority, the set
returned by SpdySession.getActiveStream() will not include all of them,
because it uses TreeSet and only compares the priority of streams. If
two different streams have the same priority, one of them will be
discarded by TreeSet.
Modification:
- Rename getActiveStreams() to activeStreams()
- Replace PriorityComparator with StreamComparator
Result:
Two different streams with the same priority are compared correctly.
Motivation:
If the requests contains uri parameters but not path the HttpRequestEncoder does produce an invalid uri while try to add the missing path.
Modifications:
Correctly handle the case of uri with paramaters but no path.
Result:
HttpRequestEncoder produce correct uri in all cases.
Motivation:
Now Netty has a few problems with null values.
Modifications:
- Check HAProxyProxiedProtocol in HAProxyMessage constructor and throw NPE if it is null.
If HAProxyProxiedProtocol is null we will set AddressFamily as null. So we will get NPE inside checkAddress(String, AddressFamily) and it won't be easy to understand why addrFamily is null.
- Check File in DiskFileUpload.toString().
If File is null we will get NPE when calling toString() method.
- Check Result<String> in MqttDecoder.decodeConnectionPayload(...).
If !mqttConnectVariableHeader.isWillFlag() || !mqttConnectVariableHeader.hasUserName() || !mqttConnectVariableHeader.hasPassword() we will get NPE when we will try to create new instance of MqttConnectPayload.
- Check Unsafe before calling unsafe.getClass() in PlatformDependent0 static block.
- Removed unnecessary null check in WebSocket08FrameEncoder.encode(...).
Because msg.content() can not return null.
- Removed unnecessary null check in DefaultStompFrame(StompCommand) constructor.
Because we have this check in the super class.
- Removed unnecessary null checks in ConcurrentHashMapV8.removeTreeNode(TreeNode<K,V>).
- Removed unnecessary null check in OioDatagramChannel.doReadMessages(List<Object>).
Because tmpPacket.getSocketAddress() always returns new SocketAddress instance.
- Removed unnecessary null check in OioServerSocketChannel.doReadMessages(List<Object>).
Because socket.accept() always returns new Socket instance.
- Pass Unpooled.buffer(0) instead of null inside CloseWebSocketFrame(boolean, int) constructor.
If we will pass null we will get NPE in super class constructor.
- Added throw new IllegalStateException in GlobalEventExecutor.awaitInactivity(long, TimeUnit) if it will be called before GlobalEventExecutor.execute(Runnable).
Because now we will get NPE. IllegalStateException will be better in this case.
- Fixed null check in OpenSslServerContext.setTicketKeys(byte[]).
Now we throw new NPE if byte[] is not null.
Result:
Added new null checks when it is necessary, removed unnecessary null checks and fixed some NPE problems.
Modifications:
- Added a static modifier for CompositeByteBuf.Component.
This class is an inner class, but does not use its embedded reference to the object which created it. This reference makes the instances of the class larger, and may keep the reference to the creator object alive longer than necessary.
- Removed unnecessary boxing/unboxing operations in HttpResponseDecoder, RtspResponseDecoder, PerMessageDeflateClientExtensionHandshaker and PerMessageDeflateServerExtensionHandshaker
A boxed primitive is created from a String, just to extract the unboxed primitive value.
- Removed unnecessary 3 times calculations in DiskAttribute.addContent(...).
- Removed unnecessary checks if file exists before call mkdirs() in NativeLibraryLoader and PlatformDependent.
Because the method mkdirs() has this check inside.
- Removed unnecessary `instanceof AsciiString` check in StompSubframeAggregator.contentLength(StompHeadersSubframe) and StompSubframeDecoder.getContentLength(StompHeaders, long).
Because StompHeaders.get(CharSequence) always returns java.lang.String.
Motivation:
When we receive an incomplete WebSocketFrame we need to make sure to wait for more data. Because we not did this we could produce a NPE.
Modification:
Make sure we not try to add null into the RecyclableArrayList
Result:
no more NPE on incomplete frames.
Motivation:
HTTP header validation can be expensive so we should allow to disable it like we do in HttpObjectDecoder.
Modification:
Add constructor argument to disable validation.
Result:
Performance improvement
Motivation:
HttpObjectAggregator currently creates a new FullHttpResponse / FullHttpRequest for each message it needs to aggregate. While doing so it also creates 2 DefaultHttpHeader instances (one for the headers and one for the trailing headers). This is bad for two reasons:
- More objects are created then needed and also populate the headers is not for free
- Headers may get validated even if the validation was disabled in the decoder
Modification:
- Wrap the previous created HttpResponse / HttpRequest and so reuse the original HttpHeaders
- Reuse the previous created trailing HttpHeader.
- Fix a bug where the trailing HttpHeader was incorrectly mixed in the headers.
Result:
- Less GC
- Faster HttpObjectAggregator implementation
Motivation:
HttpOrSpdyChooser can be simplified so the user not need to implement getProtocol(...) method.
Modification:
Add implementation for the method. The user can override it if necessary.
Result:
Easier usage of HttpOrSpdyChooser.
Motivation:
DecodeResult is dropped when aggregate HTTP messages.
Modification:
Make sure we not drop the DecodeResult while aggregate HTTP messages.
Result:
Correctly include the DecodeResult for later processing.
Motivation:
Due to integer overflow bug, writes of FileRegions to http server pipeline (eg like one from HttpStaticFileServer example) with length greater than Integer.MAX_VALUE are ignored in 1/2 of cases (ie no data gets sent to client)
Modification:
Correctly handle chunk sized > Integer.MAX_VALUE
Result:
Be able to use FileRegion > Integer.MAX_VALUE when using chunked encoding.
Motivation:
Persuit for the consistency in method naming
Modifications:
- Remove the 'get' prefix from all HTTP/SPDY message classes
- Fix some inspector warnings
Result:
Consistency
Motivation:
When Netty runs in a managed environment such as web application server,
Netty needs to provide an explicit way to remove the thread-local
variables it created to prevent class loader leaks.
FastThreadLocal uses different execution paths for storing a
thread-local variable depending on the type of the current thread.
It increases the complexity of thread-local removal.
Modifications:
- Moved FastThreadLocal and FastThreadLocalThread out of the internal
package so that a user can use it.
- FastThreadLocal now keeps track of all thread local variables it has
initialized, and calling FastThreadLocal.removeAll() will remove all
thread-local variables of the caller thread.
- Added FastThreadLocal.size() for diagnostics and tests
- Introduce InternalThreadLocalMap which is a mixture of hard-wired
thread local variable fields and extensible indexed variables
- FastThreadLocal now uses InternalThreadLocalMap to implement a
thread-local variable.
- Added ThreadDeathWatcher.unwatch() so that PooledByteBufAllocator
tells it to stop watching when its thread-local cache has been freed
by FastThreadLocal.removeAll().
- Added FastThreadLocalTest to ensure that removeAll() works
- Added microbenchmark for FastThreadLocal and JDK ThreadLocal
- Upgraded to JMH 0.9
Result:
- A user can remove all thread-local variables Netty created, as long as
he or she did not exit from the current thread. (Note that there's no
way to remove a thread-local variable from outside of the thread.)
- FastThreadLocal exposes more useful operations such as isSet() because
we always implement a thread local variable via InternalThreadLocalMap
instead of falling back to JDK ThreadLocal.
- FastThreadLocalBenchmark shows that this change improves the
performance of FastThreadLocal even more.
Motivation:
We have quite a bit of code duplication between HTTP/1, HTTP/2, SPDY,
and STOMP codec, because they all have a notion of 'headers', which is a
multimap of string names and values.
Modifications:
- Add TextHeaders and its default implementation
- Add AsciiString to replace HttpHeaderEntity
- Borrowed some portion from Apache Harmony's java.lang.String.
- Reimplement HttpHeaders, SpdyHeaders, and StompHeaders using
TextHeaders
- Add AsciiHeadersEncoder to reuse the encoding a TextHeaders
- Used a dedicated encoder for HTTP headers for better performance
though
- Remove shortcut methods in SpdyHeaders
- Replace SpdyHeaders.getStatus() with HttpResponseStatus.parseLine()
Result:
- Removed quite a bit of code duplication in the header implementations.
- Slightly better performance thanks to improved header validation and
hash code calculation
Motivation:
Provide a faster ThreadLocal implementation
Modification:
Add a "FastThreadLocal" which uses an EnumMap and a predefined fixed set of possible thread locals (all of the static instances created by netty) that is around 10-20% faster than standard ThreadLocal in my benchmarks (and can be seen having an effect in the direct PooledByteBufAllocator benchmark that uses the DEFAULT ByteBufAllocator which uses this FastThreadLocal, as opposed to normal instantiations that do not, and in the new RecyclableArrayList benchmark);
Result:
Improved performance
Motivation:
According to RFC2616 section 19, boundary string could be quoted, but
currently the PostRequestDecoder does not support it while it should.
Modifications:
Once the boundary is found, one check is made to verify if the boundary
is "quoted", and if so, it is "unqoted".
Note: in following usage of this boundary (as delimiter), quote seems no
more allowed according to the same RFC, so the reason that only the
boundary definition is corrected.
Result:
Now the boundary could be whatever quoted or not. A Junit test case
checks it.
Motivation:
When an attribute is ending with an odd number of CR (0x0D), the decoder
add an extra CR in the decoded attribute and should not.
Modifications:
Each time a CR is detected, the next byte was tested to be LF or not. If
not, in a number of places, the CR byte was lost while it should not be.
When a CR is detected, if the next byte is not LF, the CR byte should be
saved as the position point to the next byte (not LF). When a CR is
detected, if there is not yet other available bytes, the position is
reset to the position of CR (since a LF could follow).
A new Junit test case is added, using DECODER and variable number of CR
in the final attribute (testMultipartCodecWithCRasEndOfAttribute).
Result:
The attribute is now correctly decoded with the right number of CR
ending bytes.
Motivation:
We have different message aggregator implementations for different
protocols, but they are very similar with each other. They all stems
from HttpObjectAggregator. If we provide an abstract class that provide
generic message aggregation functionality, we will remove their code
duplication.
Modifications:
- Add MessageAggregator which provides generic message aggregation
- Reimplement all existing aggregators using MessageAggregator
- Add DecoderResultProvider interface and extend it wherever possible so
that MessageAggregator respects the state of the decoded message
Result:
Less code duplication
Motivation:
CORS request are currently processed, and potentially failed, after the
target ChannelHandler(s) have been invoked. This might not be desired, for
example a HTTP PUT or POST might have been performed.
Modifications:
Added a shortCurcuit option to CorsConfig which when set will
cause a validation of the HTTP request's 'Origin' header and verify that
it is valid according to the configuration. If found invalid an 403
"Forbidden" response will be returned and not further processing will
take place.
This is indeed no help for non browser request, like using curl, which
can set the 'Origin' header.
Result:
Users can now configure if the 'Origin' header should be validated
upfront and have the request rejected before any further processing
takes place.
Motivation:
Because of not correctly release a buffer before null out the reference a memory leak shows up.
Modifications:
Correct call buffer.release() before null out reference.
Result:
No more leak
Motivation:
Currently there's no way to configure maxFramePayloadSize from
WebSocketServerProtocolHandler, which is the most used entry point of
WebSocket server.
Modifications:
Added another constructor for maxFramePayloadSize.
Result:
We can configure max frame size for websocket packet in
WebSocketServerProtocolHandler. It will also keep backward compatibility
with default max size: 65536. (65536 is hard-coded max size in previous
version of Netty)
Motivation:
Before we aggregated the full text in the WebSocket08FrameDecoder just to fill in the ContinuationWebSocketFrame.aggregatedText(). The problem was that there was no upper-limit and so it would be possible to see an OOME if the remote peer sends a TextWebSocketFrame + a never ending stream of ContinuationWebSocketFrames. Furthermore the aggregation does not really belong in the WebSocket08FrameDecoder, as we provide an extra ChannelHandler for this anyway (WebSocketFrameAggregator).
Modification:
Remove the ContinuationWebSocketFrame.aggregatedText() method and corresponding constructor. Also refactored WebSocket08FrameDecoder a bit to me more efficient which is now possible as we not need to aggregate here.
Result:
No more risk of OOME because of frames.
Motivation:
When CORS has been configured to allow "*" origin, and at the same time
is allowing credentials/cookies, this causes an error from the browser
because when the response 'Access-Control-Allow-Credentials' header
is true, the 'Access-Control-Allow-Origin' must be an actual origin.
Modifications:
Changed CorsHandler setOrigin method to check for the combination of "*"
origin and allowCredentials, and if the check matches echo the CORS
request's 'Origin' value.
Result:
This addition enables the echoing of the request 'Origin' value as the
'Access-Control-Allow-Origin' value when the server has been configured
to allow any origin in combination with allowCredentials.
This allows client requests to succeed when expecting the server to
be able to handle "*" origin and at the same time be able to send cookies
by setting 'xhr.withCredentials=true'. A concrete example of this is
the SockJS protocol which expects behaviour.
Motivation:
4 and 5 were diverged long time ago and we recently reverted some of the
early commits in master. We must make sure 4.1 and master are not very
different now.
Modification:
Fix found differences
Result:
4.1 and master got closer.
Motivation:
4 and 5 were diverged long time ago and we recently reverted some of the
early commits in master. We must make sure 4.1 and master are not very
different now.
Modification:
Fix found differences
Result:
4.1 and master got closer.
Motivation:
Make it more clear what the output of HttpObjectAggregator is and that it need to come after the encoder in the pipeline.
Modifications:
Change javadocs to make things more clear.
Result:
Better docs
Motivation:
Fix leaks reported during running SpdyFrameDecoderTest
Modifications:
Make sure the produced buffers of SpdyFrameDecoder and SpdyFrameDecoderTest are released
Result:
No more leak reports during run the tests.
Motivation:
Fix leaks reported during running SpdyFrameDecoderTest
Modifications:
Make sure the produced buffer of SpdyFrameDecoder is released
Result:
No more leak reports during run the tests.
Motivation:
Fix leaks reported during SPDY test.
Modifications:
Use ReferenceCountUtil.releaseLater(...) to make sure everything is released once the tests are done.
Result:
No more leak reports during run the tests.
Motivation:
Currently, the SPDY frame encoding and decoding code is based upon
the ChannelHandler abstraction. This requires maintaining multiple
versions for 3.x and 4.x (and possibly 5.x moving forward).
Modifications:
The SPDY frame encoding and decoding code is separated from the
ChannelHandler and SpdyFrame abstractions. Also test coverage is
improved.
Result:
SpdyFrameCodec now implements the ChannelHandler abstraction and is
responsible for creating and handling SpdyFrame objects.
Motivation:
Currently the CORS support only handles a single origin, or a wildcard
origin. This task should enhance Netty's CORS support to allow multiple
origins to be specified. Just being allowed to specify one origin is
particulary limiting when a site support both http and https for
example.
Modifications:
- Updated CorsConfig and its Builder to accept multiple origins.
Result:
Users are now able to configure multiple origins for CORS.
[https://github.com/netty/netty/issues/2346]
Motivation:
Previously, we used URLDecoder.decode(...) to decode url-encoded data. This generates a lot of garbage and takes a considerable amount of time.
Modifications:
Replace URLDecoder.decode(...) with QueryStringDecoder.decodeComponent(...)
Result:
Less garbage to GC and faster decode processing.
Motivation:
When running the build with Java 8 the following error occurred:
java: reference to preflightResponseHeader is ambiguous
both method
<T>preflightResponseHeader(java.lang.CharSequence,java.lang.Iterable<T>)
in io.netty.handler.codec.http.cors.CorsConfig.Builder and method
<T>preflightResponseHeader(java.lang.String,java.util.concurrent.Callable<T>)
in io.netty.handler.codec.http.cors.CorsConfig.Builder match
The offending class was CorsConfigTest and its shouldThrowIfValueIsNull
which contained the following line:
withOrigin("*").preflightResponseHeader("HeaderName", null).build();
Modifications:
Updated the offending method with to supply a type, and object array, to
avoid the error.
Result:
After this I was able to build with Java 7 and Java 8
Motivation:
An intermediary like a load balancer might require that a Cross Origin
Resource Sharing (CORS) preflight request have certain headers set.
As a concrete example the Elastic Load Balancer (ELB) requires the
'Date' and 'Content-Length' header to be set or it will fail with a 502
error code.
This works is an enhancement of https://github.com/netty/netty/pull/2290
Modifications:
CorsConfig has been extended to make additional HTTP response headers
configurable for preflight responses. Since some headers, like the
'Date' header need to be generated each time, m0wfo suggested using a
Callable.
Result:
By default, the 'Date' and 'Content-Lenght' headers will be sent in a
preflight response. This can be overriden and users can specify
any headers that might be required by different intermediaries.
Motivation:
If the last item analyzed in a previous received HttpChunk/HttpContent was a part of an attribute's name, the read index was not set to the new right place and therefore raizing an exception in some case (since the "new" name analyzed is empty, which is not allowed so the exception).
What appears there is that the read index should be reset to the last valid position encountered whatever the case. Currently it was set when only when there is an attribute not already finished (name is ok, but content is possibly not).
Therefore the issue is that elements could be rescanned multiple times (including completed elements) and moreover some bad decoding can occur such as when in a middle of an attribute's name.
Modifications:
To fix this issue, since "firstpos" contains the last "valid" read index of the decoding (when finding a '&', '=', 'CR/LF'), we should add the setting of the read index for the following cases:
'lastchunk' encountered, therefore finishing the current buffer
any other cases than current attribute is not finished (name not found yet in particular)
So adding for this 2 cases:
undecodedChunk.readerIndex(firstpos);
Result:
Now the decoding is done once, content is added from chunk/content to chunk/content, name is decoded correctly even if in the middle of 2 chunks/contents.
A Junit test code was added: testChunkCorrect that should not raized any exception.
Motivation:
When an HttpResponseDecoder decodes an invalid chunk, a LastHttpContent instance is produced and the decoder enters the 'BAD_MESSAGE' state, which is not supposed to produce a message any further. However, because HttpObjectDecoder.invalidChunk() did not clear this.message out to null, decodeLast() will produce another LastHttpContent message on a certain situation.
Modification:
Do not forget to null out HttpObjectDecoder.message in invalidChunk(), and add a test case for it.
Result:
No more consecutive LastHttpContent messages produced by HttpObjectDecoder.
Motivation:
Currently, it is impossible to give a user the full control over what to do in response to the request with 'Expect: 100-continue' header. Currently, a user have to do one of the following:
- Accept the request and respond with 100 Continue, or
- Send the reject response and close the connection.
.. which means it is impossible to send the reject response and keep the connection alive so that the client sends additional requests.
Modification:
Added a public method called 'reset()' to HttpObjectDecoder so that a user can reset the state of the decoder easily. Once called, the decoder will assume the next input will be the beginning of a new request.
HttpObjectAggregator now calls `reset()`right after calling 'handleOversizedMessage()' so that the decoder can continue to decode the subsequent request even after the request with 'Expect: 100-continue' header is rejected.
Added relevant unit tests / Minor clean-up
Result:
This commit completes the fix of #2211
- Related: #2163
- Add ResourceLeakHint to allow a user to provide a meaningful information about the leak when touching it
- DefaultChannelHandlerContext now implements ResourceLeakHint to tell where the message is going.
- Cleaner resource leak report by excluding noisy stack trace elements
- Related issues: #1937#1938 and #1946
- Add InterfaceHttpPostRequestDecoder and Make HttpPostRequestDecoder implement it
- HttpPostRequestDecoder actually delegates itself to HttpPostStandardRequestDecoder or HttpPostMultipartRequestDecoder
- Remove IncompatibleDataDecoderException because it's not thrown anywhere now
NPN server providers return a String version of the negotiated protocol
and the getProtocolByName method allows to easily get an instance of
the SelectedProtocol enum and avoid the need for a switch statement in
each subclass to match the String against the enum value.
- Since Netty 4, HTTP decoder does not generate a full message at all. Therefore, there's no need to keep separate states for the content smaller than maxChunkSize.
- maxChunkSize must be greater than 0. Setting it to 0 should not disable chunked encoding. We have a dedicated flag for that.
- Uncommented the tests that were commented out for an unknown reason, with some fixes.
- Added more tests for HTTP decoder.
- Removed the Ignore annotation on some tests.
- Fixes#2003 properly
- Instead of using 'bundle' packaging, use 'jar' packaging. This is
more robust because some strict build tools fail to retrieve the
artifacts from a Maven repository unless their packaging is not 'jar'.
- All artifacts now contain META-INF/io.netty.version.properties, which
provides the detailed information about the build and repository.
- Removed OSGi testsuite temporarily because it gives false errors
during split package test and examination.
- Add io.netty.util.Version for easy retrieval of version information
- This commit allows a user to write its first web socket frame right after calling WebSocketServerHandshaker.handshake() rather than adding a listener to the future it returns.
- Should fix#1933
encode of chunked content is not the most common pattern so moving it to an extra method makes it possible to inline the rest as it is a smaller method now.
* Minimize allocation of StringBuilder and also minimize char array copy
* Try to detect HttpVersion without calling toUpperCase() for performance reasons
- write() now accepts a ChannelPromise and returns ChannelFuture as most
users expected. It makes the user's life much easier because it is
now much easier to get notified when a specific message has been
written.
- flush() does not create a ChannelPromise nor returns ChannelFuture.
It is now similar to what read() looks like.
DefaultChannelHandlerContext does not trigger exceptionCaught() immediately when ChannelOutboundHandler.write() raises an exception. It just records the exception until flush() is triggered. On invokeFlush(), if there's any exception recorded, DefaultChannelHandlerContext will fail the promise without calling ChannelOutboundHandler.flush(). If more than one exception were raised, only the first exception is used as the cause of the failure and the others will be logged at warn level.
- Remove channelReadSuspended because it's actually same with messageReceivedLast
- Rename messageReceived to channelRead
- Rename messageReceivedLast to channelReadComplete
We renamed messageReceivedLast to channelReadComplete because it
reflects what it really is for. Also, we renamed messageReceived to
channelRead for consistency in method names.
I must admit MesageList was pain in the ass. Instead of forcing a
handler always loop over the list of messages, this commit splits
messageReceived(ctx, list) into two event handlers:
- messageReceived(ctx, msg)
- mmessageReceivedLast(ctx)
When Netty reads one or more messages, messageReceived(ctx, msg) event
is triggered for each message. Once the current read operation is
finished, messageReceivedLast() is triggered to tell the handler that
the last messageReceived() was the last message in the current batch.
Similarly, for outbound, write(ctx, list) has been split into two:
- write(ctx, msg)
- flush(ctx, promise)
Instead of writing a list of message with a promise, a user is now
supposed to call write(msg) multiple times and then call flush() to
actually flush the buffered messages.
Please note that write() doesn't have a promise with it. You must call
flush() to get notified on completion. (or you can use writeAndFlush())
Other changes:
- Because MessageList is completely hidden, codec framework uses
List<Object> instead of MessageList as an output parameter.
- SimpleChannelInboundHandler now has a constructor parameter to let a
user decide to enable automatic message release. (the default is to
enable), which makes ChannelInboundConsumingHandler of less value.
* This fix the bug which caused an UnsupportedOperationException when renameTo(...) was called and the underlying ByteBuf was backed by multiple ByteBuffers
The API changes made so far turned out to increase the memory footprint
and consumption while our intention was actually decreasing them.
Memory consumption issue:
When there are many connections which does not exchange data frequently,
the old Netty 4 API spent a lot more memory than 3 because it always
allocates per-handler buffer for each connection unless otherwise
explicitly stated by a user. In a usual real world load, a client
doesn't always send requests without pausing, so the idea of having a
buffer whose life cycle if bound to the life cycle of a connection
didn't work as expected.
Memory footprint issue:
The old Netty 4 API decreased overall memory footprint by a great deal
in many cases. It was mainly because the old Netty 4 API did not
allocate a new buffer and event object for each read. Instead, it
created a new buffer for each handler in a pipeline. This works pretty
well as long as the number of handlers in a pipeline is only a few.
However, for a highly modular application with many handlers which
handles connections which lasts for relatively short period, it actually
makes the memory footprint issue much worse.
Changes:
All in all, this is about retaining all the good changes we made in 4 so
far such as better thread model and going back to the way how we dealt
with message events in 3.
To fix the memory consumption/footprint issue mentioned above, we made a
hard decision to break the backward compatibility again with the
following changes:
- Remove MessageBuf
- Merge Buf into ByteBuf
- Merge ChannelInboundByte/MessageHandler and ChannelStateHandler into ChannelInboundHandler
- Similar changes were made to the adapter classes
- Merge ChannelOutboundByte/MessageHandler and ChannelOperationHandler into ChannelOutboundHandler
- Similar changes were made to the adapter classes
- Introduce MessageList which is similar to `MessageEvent` in Netty 3
- Replace inboundBufferUpdated(ctx) with messageReceived(ctx, MessageList)
- Replace flush(ctx, promise) with write(ctx, MessageList, promise)
- Remove ByteToByteEncoder/Decoder/Codec
- Replaced by MessageToByteEncoder<ByteBuf>, ByteToMessageDecoder<ByteBuf>, and ByteMessageCodec<ByteBuf>
- Merge EmbeddedByteChannel and EmbeddedMessageChannel into EmbeddedChannel
- Add SimpleChannelInboundHandler which is sometimes more useful than
ChannelInboundHandlerAdapter
- Bring back Channel.isWritable() from Netty 3
- Add ChannelInboundHandler.channelWritabilityChanges() event
- Add RecvByteBufAllocator configuration property
- Similar to ReceiveBufferSizePredictor in Netty 3
- Some existing configuration properties such as
DatagramChannelConfig.receivePacketSize is gone now.
- Remove suspend/resumeIntermediaryDeallocation() in ByteBuf
This change would have been impossible without @normanmaurer's help. He
fixed, ported, and improved many parts of the changes.
