Motivation:
The HTTP/2 specification requires the pad length field of DATA, HEADERS and PUSH_PROMISE frames to be counted towards the flow control window. The current implementation doesn't do so (See #5434).
Furthermore, it's currently not possible to add one byte padding, as this would add the one byte pad length field as well as append one padding byte to the end of the frame.
Modifications:
Include the one byte pad length field in the padding parameter of the API. Thereby extending the allowed value range by one byte to 256 (inclusive). On the wire, a one byte padding is encoded with a pad length field with value zero and a 256 byte padding is encoded with a pad length field with value 255 and 255 bytes append to the end of the frame.
Result:
More correct padding.
Related: #4333#4421#5128
Motivation:
slice(), duplicate() and readSlice() currently create a non-recyclable
derived buffer instance. Under heavy load, an application that creates a
lot of derived buffers can put the garbage collector under pressure.
Modifications:
- Add the following methods which creates a non-recyclable derived buffer
- retainedSlice()
- retainedDuplicate()
- readRetainedSlice()
- Add the new recyclable derived buffer implementations, which has its
own reference count value
- Add ByteBufHolder.retainedDuplicate()
- Add ByteBufHolder.replace(ByteBuf) so that..
- a user can replace the content of the holder in a consistent way
- copy/duplicate/retainedDuplicate() can delegate the holder
construction to replace(ByteBuf)
- Use retainedDuplicate() and retainedSlice() wherever possible
- Miscellaneous:
- Rename DuplicateByteBufTest to DuplicatedByteBufTest (missing 'D')
- Make ReplayingDecoderByteBuf.reject() return an exception instead of
throwing it so that its callers don't need to add dummy return
statement
Result:
Derived buffers are now recycled when created via retainedSlice() and
retainedDuplicate() and derived from a pooled buffer
Motivation:
Some codecs should be considered unstable as these are relative new. For this purpose we should introduce an annotation which these codecs should us to be marked as unstable in terms of API.
Modifications:
- Add UnstableApi annotation and use it on codecs that are not stable
- Move http2.hpack to http2.internal.hpack as it is internal.
Result:
Better document unstable APIs.
Motivation:
We lately added ByteBuf.isReadOnly() which allows to detect if a buffer is read-only or not. We should add ByteBuf.asReadOnly() to allow easily access a read-only version of a buffer.
Modifications:
- Add ByteBuf.asReadOnly()
- Deprecate Unpooled.unmodifiableBuffer(Bytebuf)
Result:
More consistent api.
Motivation:
Http2Codec.SimpleChannelPromiseAggregator currently fails fast if as soon as a tryFailure or setFailure method is called. This can lead to write operations which pass the result of SimpleChannelPromiseAggregator.newPromise to multiple channel.write calls throwing exceptions due to the promise being already done. This behavior is not expected by most of the Netty codecs (SslHandler) and can also create unexpected leaks in the http2 codec (DefaultHttp2FrameWriter).
Modifications:
- Http2Codec.SimpleChannelPromiseAggregator shouldn't complete the promise until doneAllocatingPromises is called
- Usages of Http2Codec.SimpleChannelPromiseAggregator should be adjusted to handle the change in behavior
- What were leaks in DefaultHttp2FrameWriter should be fixed to catch any other cases where ctx.write may throw
Result:
SimpleChannelPromiseAggregator won't generate promises which are done when newPromise is called.
Motivation:
Some times the user wants to set a Http2HeaderEncoder.SensitivityDetector when building a Http2ConnectionHandler.
Modifications:
Allow to set Http2HeaderEncoder.SensitivityDetector via builder.
Result:
More flexible building of Http2ConnectionHandler possible.
Motivation:
The encoder is currently responsible for chunking frames when writing in order to conform to max frame size. The frame writer would be a better place for this since it could perform a reuse the same promise aggregator for all the write and could also perform a single allocation for all of the frame headers.
Modifications:
Modified `DefaultHttp2FrameWriter` to perform the chunking and modified the contract in the `Http2FrameWriter` interface. Modified `DefaultHttp2ConnectionEncoder` to send give all allocated bytes to the writer.
Result:
Fixes#3966
Motivation:
The HTTP/2 spec states that the ping frame length must be 8 and is otherwise an error https://tools.ietf.org/html/rfc7540#section-6.7. The DefaultHttp2FrameReader enforces this, but the DefaultHttp2FrameWriter allows invalid frames to be written. We should not allow invalid ping frames to be written to the network.
Modifications:
- DefaultHttp2FrameWriter checks the frame size to be 8, or throws an exception
Result:
Fixes https://github.com/netty/netty/issues/3721
Motivation:
We should support XXXCollections methods for all primitive map types.
Modifications:
Removed PrimitiveCollections and added a template for XXXCollections.
Result:
Fixes#4001
Motivation:
It would be useful to support the Java `Map` interface in our primitive maps.
Modifications:
Renamed current methods to "pXXX", where p is short for "primitive". Made the template for all primitive maps extend the appropriate Map interface.
Result:
Fixes#3970
Motivation:
Now that we have a CharObjectHashMap, we should change Http2Settings to use it.
Modifications:
Changed Http2Settings to extend CharObjectHashMap rather than IntObjectHashMap.
Result:
Http2Settings uses less memory to store keys.
Motivation:
A microbenchmark will be useful to get a baseline for performance.
Modifications:
- Introduce a new microbenchmark which tests the Http2DefaultFrameWriter.
- Allow benchmarks to run without thread context switching between JMH and Netty.
Result:
Microbenchmark exists to test performance.
Motivation:
The Http2DefaultFrameWriter copies all contents into a buffer (or uses a CompositeBuffer in 1 case) and then writes that buffer to the socket. There is an opportunity to avoid the copy operations and write directly to the socket.
Modifications:
- Http2DefaultFrameWriter should avoid copy operations where possible.
- The Http2FrameWriter interface should be clarified to indicate that ByteBuf objects will be released.
Result:
Hopefully less allocation/copy leads to memory and throughput performance benefit.
Motivation:
HTTP/2 codec was implemented in master branch.
Since, master is not yet stable and will be some time before it gets released, backporting it to 4.1, enables people to use the codec with a stable netty version.
Modification:
The code has been copied from master branch as is, with minor modifications to suit the `ChannelHandler` API in 4.x.
Apart from that change, there are two backward incompatible API changes included, namely,
- Added an abstract method:
`public abstract Map.Entry<CharSequence, CharSequence> forEachEntry(EntryVisitor<CharSequence> visitor)
throws Exception;`
to `HttpHeaders` and implemented the same in `DefaultHttpHeaders` as a delegate to the internal `TextHeader` instance.
- Added a method:
`FullHttpMessage copy(ByteBuf newContent);`
in `FullHttpMessage` with the implementations copied from relevant places in the master branch.
- Added missing abstract method related to setting/adding short values to `HttpHeaders`
Result:
HTTP/2 codec can be used with netty 4.1
