Motivation:
In next major version of netty users should use ChannelHandler everywhere. We should ensure we do the same
Modifications:
Replace usage of deprecated classes / interfaces with ChannelHandler
Result:
Use non-deprecated code
Motivation
Per javadoc in 4.1.x SimpleChannelInboundHandler:
"Please keep in mind that channelRead0(ChannelHandlerContext, I) will be
renamed to messageReceived(ChannelHandlerContext, I) in 5.0."
Modifications
Rename aforementioned method and all references/overrides.
Result
Method is renamed.
Motivation
The current event loop shutdown logic is quite fragile and in the
epoll/NIO cases relies on the default 1 second wait/select timeout that
applies when there are no scheduled tasks. Without this default timeout
the shutdown would hang indefinitely.
The timeout only takes effect in this case because queued scheduled
tasks are first cancelled in
SingleThreadEventExecutor#confirmShutdown(), but I _think_ even this
isn't robust, since the main task queue is subsequently serviced which
could result in some new scheduled task being queued with much later
deadline.
It also means shutdowns are unnecessarily delayed by up to 1 second.
Modifications
- Add/extend unit tests to expose the issue
- Adjust SingleThreadEventExecutor shutdown and confirmShutdown methods
to explicitly add no-op tasks to the taskQueue so that the subsequent
event loop iteration doesn't enter blocking wait (as looks like was
originally intended)
Results
Faster and more robust shutdown of event loops, allows removal of the default wait timeout.
This is a port of https://github.com/netty/netty/pull/9616
Motivation:
We should correctly reset the cached local and remote address when a Channel.disconnect() is called and the channel has a notion of disconnect vs close (for example DatagramChannel implementations).
Modifications:
- Correctly reset cached kicak abd remote address
- Update testcase to cover it and so ensure all transports work in a consistent way
Result:
Correctly handle disconnect()
Motivation:
291f80733a introduced a change to use a byte[] to construct the InetAddress when receiving datagram messages to reduce the overhead. Unfortunally it introduced a regression when handling IPv6-mapped-IPv4 addresses and so produced an IndexOutOfBoundsException when trying to fill the byte[] in native code.
Modifications:
- Correctly use the offset on the pointer of the address.
- Add testcase
- Make tests more robust and include more details when the test fails
Result:
No more IndexOutOfBoundsException
Motivation:
We should also use sendmmsg on connected channels whenever possible to reduce the overhead of syscalls.
Modifications:
No matter if the channel is connected or not try to use sendmmsg when supported to reduce the overhead of syscalls
Result:
Better performance on connected UDP channels due less syscalls
Motivation:
394a1b3485 introduced the possibility to use recvmmsg(...) but did not correctly handle ipv6 mapped ip4 addresses to make it consistent with other transports.
Modifications:
- Correctly handle ipv6 mapped ipv4 addresses by only copy over the relevant bytes
- Small improvement on how to detect ipv6 mapped ipv4 addresses by using memcmp and not byte by byte compare
- Adjust test to cover this bug
Result:
Correctly handle ipv6 mapped ipv4 addresses
Motivation:
At the moment it is quite easy to hit reentrance issues when you have multiple handlers in the pipeline and each of the handlers does not correctly protect against these. To make it easier for the user we should try to protect from these. The issue is usually if and inbound event will trigger and outbound event and this outbound event then against triggeres an inbound event. This may result in having methods in a ChannelHandler re-enter some method and so state can be corrupted or messages be re-ordered.
Modifications:
- Keep track of inbound / outbound operations in DefaultChannelHandlerContext and if reentrancy is detected break it by scheduling the action on the EventLoop. This will then be picked up once the method returns and so the reentrancy is broken up.
- Adjust tests which made strange assumptions about execution order
Result:
No more reentrancy of handlers possible.
Motivation:
If all we need is the FileChannel we should better use RandomAccessFile as FileInputStream and FileOutputStream use a finalizer.
Modifications:
Replace FileInputStream and FileOutputStream with RandomAccessFile when possible.
Result:
Fixes https://github.com/netty/netty/issues/8078.
Motivation:
We did not have support for enable / disable loopback mode in our native epoll transport and also missed the implemention to access the configured interface.
Modifications:
Add implementation and adjust test to cover it
Result:
More complete multicast support with native epoll transport
Motivation:
Provide epoll/native multicast to support high load multicast users (we are using it for a high load telecomm app at my day job).
Modification:
Added support for source specific and any source multicast for epoll transport. Some caveats: no support for disabling loop back mode, retrieval of interface and block operation, all of which tend to be less frequently used.
Result:
Provides epoll transport multicast for common use cases.
Co-authored-by: Norman Maurer <norman_maurer@apple.com>
Motivation:
The current KQueueEventLoop implementation does not process concurrent domain socket channel registration/unregistration in the order they actual
happen since unregistration are delated by an event loop task scheduling. When a domain socket is closed, it's file descriptor might be reused
quickly and therefore trigger a new channel registration using the same descriptor.
Consequently the KQueueEventLoop#add(AbstractKQueueChannel) method will overwrite the current inactive channels having the same descriptor
and the delayed KQueueEventLoop#remove(AbstractKQueueChannel) will remove the active channel that replaced the inactive one.
As active channels are registered, events for this file descriptor won't be processed anymore and the channels will never be closed.
The same problem can also happen in EpollEventLoop. Beside this we also may never remove the AbstractEpollChannel from the internal map
when it is unregistered which will prevent it from be GC'ed
Modifications:
- Change logic of native KQueue and Epoll implementations to ensure we correctly handle the case of FD reuse
- Only try to update kevent / epoll if the Channel is still open (as otherwise it will be handled by kqueue / epoll itself)
- Correctly remove AbstractEpollChannel from internal map in all cases
- Make implementation of closeAll() consistent for Epoll and KQueueEventLoop
Result:
KQueue and Epoll native transports correctly handle FD reuse
Co-authored-by: Norman Maurer <norman_maurer@apple.com>
Motivation:
86dd388637 reverted the usage of IPv6 Multicast test. This commit makes the whole multicast testing a lot more robust by selecting the correct interface in any case and also reverts the `@Ignore`
Modifications:
- More robust multicast testing by selecting the right NetworkInterface
- Remove the `@Ignore` again for the IPv6 test
Result:
More robust multicast testing
Motivation:
The multicast ipv6 test fails on some systems. As I just added it let me ignore it for now while investigating.
Modifications:
Add @ignore
Result:
Stable testsuite while investigate
Motivation:
We currently only cover ipv4 multicast in the testsuite but we should also have tests for ipv6.
Modifications:
- Add test for ipv6
- Ensure we only try to run multicast test for ipv4 / ipv6 if the loopback interface supports it.
Result:
Better test coverage
Motivation:
We should not throw check exceptions when the user calls sync*() but should better wrap it in a CompletionException to make it easier for people to reason about what happens.
Modifications:
- Change sync*() to throw CompletionException
- Adjust tests
- Add some more tests
Result:
Fixes https://github.com/netty/netty/issues/8521.
Motivation:
In 42742e233f we already added default methods to Channel*Handler and deprecated the Adapter classes to simplify the class hierarchy. With this change we go even further and merge everything into just ChannelHandler. This simplifies things even more in terms of class-hierarchy.
Modifications:
- Merge ChannelInboundHandler | ChannelOutboundHandler into ChannelHandler
- Adjust code to just use ChannelHandler
- Deprecate old interfaces.
Result:
Cleaner and simpler code in terms of class-hierarchy.
Motivation:
Since DomainSocketChannel is a DuplexChannel, which be able to shutdown input or output individually on demands, but ALLOW_HALF_CLOSURE channel option has not been supported yet.
I thought this could be a missing feature of Unix domain socket, so here the PR for it.
Modifications:
1. Added allHalfClosure property both in EpollDomainSocketChannelConfig and KQueueDomainSocketChannelConfig,
2. Enabled isAllowHalfClosure method of native channel to support domain channel config,
3. Created EpollDomainSocketShutdownOutputByPeerTest and KQueueDomainSocketShutdownOutputByPeerTest to verify the change.
Result:
ALLOW_HALF_CLOSURE channel option can be set with DomainSocketChannel, and no more warning of Unknown channel option 'ALLOW_HALF_CLOSURE'.
Motivation:
As we now us java8 as minimum java version we can deprecate ChannelInboundHandlerAdapter / ChannelOutboundHandlerAdapter and just move the default implementations into the interfaces. This makes things a bit more flexible for the end-user and also simplifies the class-hierarchy.
Modifications:
- Mark ChannelInboundHandlerAdapter and ChannelOutboundHandlerAdapter as deprecated
- Add default implementations to ChannelInboundHandler / ChannelOutboundHandler
- Refactor our code to not use ChannelInboundHandlerAdapter / ChannelOutboundHandlerAdapter anymore
Result:
Cleanup class-hierarchy and make things a bit more flexible.
Motivation:
Netty is very widely used which can lead to a lot of pain when we break API / ABI. We should make use japicmp-maven-plugin during the build to verify we do not introduce breakage by mistake.
Modifications:
- Add japicmp-maven-plugin to the build process
- Fix a method signature change in HttpProxyHandler that was flagged as a possible problem.
Result:
Ensure no API/ABI breakage accour between releases.
Motivation:
`DefaultFileRegion.transferTo` will return 0 all the time when we request more data then the actual file size. This may result in a busy spin while processing the fileregion during writes.
Modifications:
- If we wrote 0 bytes check if the underlying file size is smaller then the requested count and if so throw an IOException
- Add DefaultFileRegionTest
- Add a test to the testsuite
Result:
Fixes https://github.com/netty/netty/issues/8868.
Motivation:
The SSLEngine does provide a way to signal to the caller that it may need to execute a blocking / long-running task which then can be offloaded to an Executor to ensure the I/O thread is not blocked. Currently how we handle this in SslHandler is not really optimal as while we offload to the Executor we still block the I/O Thread.
Modifications:
- Correctly support offloading the task to the Executor while suspending processing of SSL in the I/O Thread
- Add new methods to SslContext to specify the Executor when creating a SslHandler
- Remove @deprecated annotations from SslHandler constructor that takes an Executor
- Adjust tests to also run with the Executor to ensure all works as expected.
Result:
Be able to offload long running tasks to an Executor when using SslHandler. Partly fixes https://github.com/netty/netty/issues/7862 and https://github.com/netty/netty/issues/7020.
Motivation:
SPDY has been superseded by HTTP/2. Chrome has dropped support in 2016 and GFE no longer negociate it.
Modifications:
* drop codec
* drop examples
* drop constants from `ApplicationProtocolNames`
Result:
SPDY support dropped from Netty 5
Motivation:
We can just use Objects.requireNonNull(...) as a replacement for ObjectUtil.checkNotNull(....)
Modifications:
- Use Objects.requireNonNull(...)
Result:
Less code to maintain.
Motivation:
In the native code EpollDatagramChannel / KQueueDatagramChannel creates a DatagramSocketAddress object for each received UDP datagram even when in connected mode as it uses the recvfrom(...) / recvmsg(...) method. Creating these is quite heavy in terms of allocations as internally, char[], String, Inet4Address, InetAddressHolder, InetSocketAddressHolder, InetAddress[], byte[] objects are getting generated when constructing the object. When in connected mode we can just use regular read(...) calls which do not need to allocate all of these.
Modifications:
- When in connected mode use read(...) and NOT recvfrom(..) / readmsg(...) to reduce allocations when possible.
- Adjust tests to ensure read works as expected when in connected mode.
Result:
Less allocations and GC when using native datagram channels in connected mode. Fixes https://github.com/netty/netty/issues/8770.
Motiviation:
In the past we allowed to use different EventExecutors for different ChannelHandlers in the ChannelPipeline. This introduced a lot of complexity while not providing much gain. Also it made the pipeline racy in terms of adding / remove handlers in some situations. This feature is not really used in the wild and can be easily archived by offloading heavy logic to an Executor by the user itself.
Modifications:
- Remove the ability to provide custom EventExecutor when adding handlers to the pipeline.
- Remove testcode that is not needed any more
- Ensure a handler is correctly visible in the pipeline when asked for it by the user while not be used until the EventLoop runs. This ensures correct ordering and visibility.
- Correctly remove ChannelHandlers from pipeline when scheduling of handlerAdded(...) callbacks fail.
Result:
Remove races in DefaultChannelPipeline and simplify implementation of AbstractChannelHandlerContext.
Motivation:
We can use lambdas now as we use Java8.
Modification:
use lambda function for all package, #8751 only migrate transport package.
Result:
Code cleanup.
Motivation:
SslContext implementations have tons of contructors, most of them deprecated as we want to enforce builder usage in Netty 5.
Cleaning them up is a requirement prior to introducing new parameters such as hostname verification.
Modifications:
* Make SslContext implementations classes and constructors package private, users are supposed to use the SslContextBuilder.
* Drop all but one constructor. The exception for now is with Jdk(Client|Server)Context that still has an additional constructor that takes an ApplicationProtocolNegotiator parameter. ApplicationProtocolNegotiator usage is supposed to be dropped in favor of ApplicationProtocolConfig and this constructor is only used in tests, so I guess it will be dropped to in a follow up.
Result:
Deprecated code dropped. Path cleaned up for introducing new features with having to introduce yet another constructor.
* Decouble EventLoop details from the IO handling for each transport to allow easy re-use of code and customization
Motiviation:
As today extending EventLoop implementations to add custom logic / metrics / instrumentations is only possible in a very limited way if at all. This is due the fact that most implementations are final or even package-private. That said even if these would be public there are the ability to do something useful with these is very limited as the IO processing and task processing are very tightly coupled. All of the mentioned things are a big pain point in netty 4.x and need improvement.
Modifications:
This changeset decoubled the IO processing logic from the task processing logic for the main transport (NIO, Epoll, KQueue) by introducing the concept of an IoHandler. The IoHandler itself is responsible to wait for IO readiness and process these IO events. The execution of the IoHandler itself is done by the SingleThreadEventLoop as part of its EventLoop processing. This allows to use the same EventLoopGroup (MultiThreadEventLoupGroup) for all the mentioned transports by just specify a different IoHandlerFactory during construction.
Beside this core API change this changeset also allows to easily extend SingleThreadEventExecutor / SingleThreadEventLoop to add custom logic to it which then can be reused by all the transports. The ideas are very similar to what is provided by ScheduledThreadPoolExecutor (that is part of the JDK). This allows for example things like:
* Adding instrumentation / metrics:
* how many Channels are registered on an SingleThreadEventLoop
* how many Channels were handled during the IO processing in an EventLoop run
* how many task were handled during the last EventLoop / EventExecutor run
* how many outstanding tasks we have
...
...
* Implementing custom strategies for choosing the next EventExecutor / EventLoop to use based on these metrics.
* Use different Promise / Future / ScheduledFuture implementations
* decorate Runnable / Callables when submitted to the EventExecutor / EventLoop
As a lot of functionalities are folded into the MultiThreadEventLoopGroup and SingleThreadEventLoopGroup this changeset also removes:
* AbstractEventLoop
* AbstractEventLoopGroup
* EventExecutorChooser
* EventExecutorChooserFactory
* DefaultEventLoopGroup
* DefaultEventExecutor
* DefaultEventExecutorGroup
Result:
Fixes https://github.com/netty/netty/issues/8514 .
Motivation:
We should leave the responsibility to choose the EventExecutor for a ChannelHandler to the user for more flexibility and to keep things simple.
Modification:
- Change method signatures to take an EventExecutor and not an EventExecutorGroup
- Remove special ChannelOption that allowed to enable / disable EventExecutor pinning
Result:
Simpler and more flexible code.
Motivation:
Custom Netty ThreadLocalRandom and ThreadLocalRandomProvider classes are no longer needed and can be removed.
Modification:
Remove own ThreadLocalRandom
Result:
Less code to maintain
Motivation:
We can use the diamond operator these days.
Modification:
Use diamond operator whenever possible.
Result:
More modern code and less boiler-plate.
Motivation:
Since Java 7 we can automatically close resources in try () construction.
Modification:
Changed all try catches in the code with autoclose try (resource)
Result:
Less boiler-plate
Motivation:
At the moment it’s possible to have a Channel in Netty that is not registered / assigned to an EventLoop until register(...) is called. This is suboptimal as if the Channel is not registered it is also not possible to do anything useful with a ChannelFuture that belongs to the Channel. We should think about if we should have the EventLoop as a constructor argument of a Channel and have the register / deregister method only have the effect of add a Channel to KQueue/Epoll/... It is also currently possible to deregister a Channel from one EventLoop and register it with another EventLoop. This operation defeats the threading model assumptions that are wide spread in Netty, and requires careful user level coordination to pull off without any concurrency issues. It is not a commonly used feature in practice, may be better handled by other means (e.g. client side load balancing), and therefore we propose removing this feature.
Modifications:
- Change all Channel implementations to require an EventLoop for construction ( + an EventLoopGroup for all ServerChannel implementations)
- Remove all register(...) methods from EventLoopGroup
- Add ChannelOutboundInvoker.register(...) which now basically means we want to register on the EventLoop for IO.
- Change ChannelUnsafe.register(...) to not take an EventLoop as parameter (as the EventLoop is supplied on custruction).
- Change ChannelFactory to take an EventLoop to create new Channels and introduce ServerChannelFactory which takes an EventLoop and one EventLoopGroup to create new ServerChannel instances.
- Add ServerChannel.childEventLoopGroup()
- Ensure all operations on the accepted Channel is done in the EventLoop of the Channel in ServerBootstrap
- Change unit tests for new behaviour
Result:
A Channel always has an EventLoop assigned which will never change during its life-time. This ensures we are always be able to call any operation on the Channel once constructed (unit the EventLoop is shutdown). This also simplifies the logic in DefaultChannelPipeline a lot as we can always call handlerAdded / handlerRemoved directly without the need to wait for register() to happen.
Also note that its still possible to deregister a Channel and register it again. It's just not possible anymore to move from one EventLoop to another (which was not really safe anyway).
Fixes https://github.com/netty/netty/issues/8513.
Motivation:
In the test we assume some semantics on how RST is done that are not true for Windows so we should skip it.
Modifications:
Skip test when on windows.
Result:
Be able to run testsuite on windows. Fixes https://github.com/netty/netty/issues/8571.
Motivation:
Most of the maven modules do not explicitly declare their
dependencies and rely on transitivity, which is not always correct.
Modifications:
For all maven modules, add all of their dependencies to pom.xml
Result:
All of the (essentially non-transitive) depepdencies of the modules are explicitly declared in pom.xml
Motivation:
This transport is unique because it uses Java's blocking IO (java.io / java.net) under the hood. However it is not clear if this transport is actually useful so it should be removed.
Modifications:
- Remove OIO transport and RXTX transport which depend on it.
- Remove Oio*Sctp* implementations
- Remove PerThreadEventLoop* which was only used by OIO transport.
Result:
Fixes https://github.com/netty/netty/issues/8510.
Motivation:
The UDT transport was marked as @Deprecated a long time ago as the underlying native library is not really maintained anymore. We should remove it as part of Netty 5.
Modifications:
Remove UDT transport
Result:
Dont try to maintain a transport which uses an unmaintained native lib internally.
Motivation:
TLSv1.3 support is included in java11 and is also supported by OpenSSL 1.1.1, so we should support when possible.
Modifications:
- Add support for TLSv1.3 using either the JDK implementation or the native implementation provided by netty-tcnative when compiled against openssl 1.1.1
- Adjust unit tests for semantics provided by TLSv1.3
- Correctly handle custom Provider implementations that not support TLSv1.3
Result:
Be able to use TLSv1.3 with netty.
