Motivation:
See #3411. A reusable ArrayList in InternalThreadLocalMap can avoid allocations in the following pattern:
```
List<...> list = new ArrayList<...>();
add something to list but never use InternalThreadLocalMap
return list.toArray(new ...[list.size()]);
```
Modifications:
Add a reusable ArrayList to InternalThreadLocalMap and update codes to use it.
Result:
Reuse a thread local ArrayList to avoid allocations.
Motivation:
WebSocketClientCompressionHandler is stateless so it should be @Sharable.
Modifications:
Add @Sharable annotation to WebSocketClientCompressionHandler, make constructor private and add static field to get the instance.
Result:
Less object creation.
Motivation:
I am use netty as a http server, it fail to decode some POST request when the request absent Content-Type in the multipart/form-data body.
Modifications:
Set content_type with default application/octet-stream to parse the uploaded file data when the Content-Type is absent in multipart request body
Result:
Can decode the http request as normal.
Motivation:
ChannelInboundHandler and ChannelOutboundHandler both can implement exceptionCaught(...) method and so we need to dispatch to both of them.
Modifications:
- Correctly first dispatch exceptionCaught to the ChannelInboundHandler but also make sure the next handler it will be dispatched to will be the ChannelOutboundHandler
- Add removeInboundHandler() and removeOutboundHandler() which allows to remove one of the combined handlers
- Let *Codec extends it and not ChannelHandlerAppender
- Remove ChannelHandlerAppender
Result:
Correctly handle events and also have same behavior as in 4.0
Motivation:
InternalAttribute doesn't extend Attribute, but its equals only returns true when it compares with an Attribute. So it will return false when comparing with itself.
Modifications:
Make sure InternalAttribute return false for non InternalAttribute objects.
Result:
InternalAttribute's equals works correctly.
Motivation:
Boxing/unboxing can be avoided.
Modifications:
Use parseInt/parseLong to avoid unnecessary boxing/unboxing.
Result:
Remove unnecessary boxing/unboxing.
Motivation:
Warnings in IDE, unclean code, negligible performance impact.
Modification:
Deletion of unused imports
Result:
No more warnings in IDE, cleaner code, negligible performance improvement.
Motivation:
I missed to reset the MessageDigest before reusing it. This bug was introduced by 79634e661b000b5f229fdde20e44fdeab15c5ae2.
Modifications:
Call reset() on the MessageDigest.
Result:
Correctly reset MessageDigest before re-using
Motivation:
Typos in javadoc, in "combine" and "recommendations", IllegalReferenceCountException
Modification:
Rename incorrect reference, typos are modified
Result:
Reference is correct, typos are fixed
Motivation:
Creating a new MessageDigest every time is wasteful, we should store them in FastThreadLocal.
Modifications:
Change WebSocketUtil to store MD5 and SHA1 MessageDigest in FastThreadLocal and use these.
Result:
Less overhead and less GC.
Motivation:
Allow passing HttpHeaders instance to DefaultHttpMessage
in order to avoid eager creation of Headers to
allow users reuse their Headers instance.
Modifications:
Added a constructor with HttpHeaders to DefaultHttpMessage,
Modified DefaultHttpResponse and DefaultHttpRequest
to receive HttpHeaders instances.
Modified DefaultFullHttpReqest and DefaultFullHttpResponse
to receive HttpHeaders, and updated `duplicate` and
`copy` to use new constructors.
Result:
Users can now pass HttpHeaders instance when
constructing Http Requests and Responses.
Motivation:
Javadoc reports errors about invalid docs.
Modifications:
Fix some errors reported by javadoc.
Result:
A lot of javadoc errors are fixed by this patch.
Motivation:
There are some wrong links and tags in javadoc.
Modifications:
Fix the wrong links and tags in javadoc.
Result:
These links will work correctly in javadoc.
Motivation:
ChunkedInput.readChunk currently takes a ChannelHandlerContext object as a parameters. All current implementations of this interface only use this object to get the ByteBufAllocator object. Thus taking a ChannelHandlerContext as a parameter is more restrictive for users of this API than necessary.
Modifications:
- Add a new method readChunk(ByteBufAllocator)
- Deprecate readChunk(ChannelHandlerContext) and updates all implementations to call readChunk(ByteBufAllocator)
Result:
API that only requires ByteBufAllocator to use ChunkedInput.
Motivation:
HttpHeaderValues.IDENTITY is an AsciiString, but was compared using equals to a String.
Modifications:
Use contentEquals instead.
Result:
Correct comparison.
Motivation:
We have websocket extension support (with compression) in old master. We should port this to 4.1
Modifications:
Backport relevant code.
Result:
websocket extension support (with compression) is now in 4.1.
Motivation:
Consistency in API design
Modifications:
- Deprecate CorsConfig.Builder and its factory methods
- Deprecate CorsConfig.DateValueGenerator
- Add CorsConfigBuilder and its factory methods
- Fix typo (curcuit -> circuit)
Result:
Consistency with other builder APIs such as SslContextBuilder and
Http2ConnectionHandlerBuilder
Motivation:
If a uri contains whitespaces we need to ensure we correctly escape these when creating the request for the handshake.
Modifications:
- Correctly encode path for uri
- Add tests
Result:
Correctly handle whitespaces when doing websocket upgrade requests.
Motivation:
HttpClientUpgradeHandler uses HttpHeaderNames.UPGRADE as the value of
the 'Connection' header, which is incorrect. It should use
HttpHeaderValues.UPGRADE instead (note Names vs Values.)
Also, HttpHeaderValues.UPGRADE should be 'upgrade' rather than
'Upgrade', as defined in:
- https://tools.ietf.org/html/rfc7230#section-6.7
Modifications:
- Use HttpHeaderValues.UPGRADE for a 'Connection' header
- Lowercase the value of HttpHeaderValues.UPGRADE
Result:
- Fixes#4508
- Correct behavior
Motivation:
On a successful protocol upgrade in HTTP, HttpClientUpgradeHandler calls
HttpClientCodec.upgradeFrom(), which removed both the HTTP encoder and
decoder from the pipeline immediately.
However, because the decoder is in the middle of the decode loop,
removing it from the pipeline immediately will cause the cumulation
buffer to be released prematurely.
This often leads to an IllegalReferenceCountException or missing first
response after the upgrade response.
Modifications:
- Remove the decoder *after* the decode loop is done
Result:
Fixes#4504
Motivation:
HttpClientUpgradeHandler currently throws an IllegalStateException when
the server sends a '101 Switching Protocols' response that has no
'Upgrade' header.
Some servers do not send the 'Upgrade' header on a successful protocol
upgrade and we could safely assume that the server accepted the
requested protocol upgrade in such a case, looking from the response
status code (101)
Modifications:
- Do not throw an IllegalStateException when the server responded 101
without a 'Upgrade' header
- Note that we still check the equality of the 'Upgrade' header when it
is present.
Result:
- Fixes#4523
- Better interoperability
Motivation:
- On the client, cookies should be sorted in decreasing order of path
length. From RFC 6265:
5.4.2. The user agent SHOULD sort the cookie-list in the following
order:
* Cookies with longer paths are listed before cookies with
shorter paths.
* Among cookies that have equal-length path fields, cookies with
earlier creation-times are listed before cookies with later
creation-times.
NOTE: Not all user agents sort the cookie-list in this order, but
this order reflects common practice when this document was
written, and, historically, there have been servers that
(erroneously) depended on this order.
Note that the RFC does not define the path length of cookies without a
path. We sort pathless cookies before cookies with the longest path,
since pathless cookies inherit the request path (and setting a path
that is longer than the request path is of limited use, since it cannot
be read from the context in which it is written).
- On the server, if there are multiple cookies of the same name, only one
of them should be encoded. RFC 6265 says:
Servers SHOULD NOT include more than one Set-Cookie header field in
the same response with the same cookie-name.
Note that the RFC does not define which cookie should be set in the case
of multiple cookies with the same name; we arbitrarily pick the last one.
Modifications:
- Changed the visibility of the 'strict' field to 'protected' in
CookieEncoder.
- Modified ClientCookieEncoder to sort cookies in decreasing order of path
length when in strict mode.
- Modified ServerCookieEncoder to return only the last cookie of a given
name when in strict mode.
- Added a fast path for both strict mode in both client and server code
for cases with only one cookie, in order avoid the overhead of sorting
and memory allocation.
- Added unit tests for the new cases.
Result:
- Cookie generation on client and server is now more conformant to RFC 6265.
Motivation:
HttpHeaders already has specific methods for such popular and simple headers like "Host", but if I need to convert POST raw body to string I need to parse complex ContentType header in my code.
Modifications:
Add getCharset and getCharsetAsString methods to parse charset from Content-Length header.
Result:
Easy to use utility method.
Motivation:
FullHttp[Request|Response].hashCode() uses a releasable object and in vulnerable to a IllegalRefCountException if that object has been released.
Modifications:
- Ensure the released object is not used.
Result:
No more IllegalRefCountException.
Motivation:
Headers and groups of headers are frequently copied and the current mechanism is slower than it needs to be.
Modifications:
Skip name validation and hash computation when they are not necessary.
Fix emergent bug in CombinedHttpHeaders identified with better testing
Fix memory leak in DefaultHttp2Headers when clearing
Added benchmarks
Result:
Faster header copying and some collateral bug fixes
Motivation:
The HTTP/2 RFC (https://tools.ietf.org/html/rfc7540#section-8.1.2) indicates that header names consist of ASCII characters. We currently use ByteString to represent HTTP/2 header names. The HTTP/2 RFC (https://tools.ietf.org/html/rfc7540#section-10.3) also eludes to header values inheriting the same validity characteristics as HTTP/1.x. Using AsciiString for the value type of HTTP/2 headers would allow for re-use of predefined HTTP/1.x values, and make comparisons more intuitive. The Headers<T> interface could also be expanded to allow for easier use of header types which do not have the same Key and Value type.
Motivation:
- Change Headers<T> to Headers<K, V>
- Change Http2Headers<ByteString> to Http2Headers<CharSequence, CharSequence>
- Remove ByteString. Having AsciiString extend ByteString complicates equality comparisons when the hash code algorithm is no longer shared.
Result:
Http2Header types are more representative of the HTTP/2 RFC, and relationship between HTTP/2 header name/values more directly relates to HTTP/1.x header names/values.
Motivation:
As part of recent efforts to rectify performance and make 4.1 headers more similar to 5.0 some methods were deprecated. Some of these methods were deprecated because they used String instead of CharSequence in the signature, which may require casting at the user level. Some of the deprecated methods have no direct alternatives and were done to inform a user the method will go away in future releases.
Modifications:
- Remove the deprecated qualifier from methods where no direct replacement exists
Result:
Less warnings in user code.
Motivation:
As toString() is often used while logging we need to ensure this produces no exception.
Modifications:
Ensure we never throw an IllegalReferenceCountException.
Result:
Be able to log without produce exceptions.
Motivation:
Http2CodecUtils has some static variables which are defined as Strings instead of CharSequence. One of these defines is used as a header name and should be AsciiString.
Modifications:
- Change the String defines in Http2CodecUtils to CharSequence
Result:
Types are more consistently using CharSequence and adding the upgrade header will require less work.
Motivation:
Currently there is a HttpConversionUtil.addHttp2ToHttpHeaders which requires a FullHttpMessage, but this may not always be available. There is no interface that can be used with just Http2Headers and HttpHeaders.
Modifications:
- add an overload for HttpConversionUtil.addHttp2ToHttpHeaders which does not take FullHttpMessage
Result:
An overload for HttpConversionUtil.addHttp2ToHttpHeaders exists which does not require FullHttpMessage.
Motivation:
As we stored the WebSocketServerHandshaker in the ChannelHandlerContext it was always null and so no close frame was send if WebSocketServerProtocolHandler was used.
Modifications:
Store WebSocketServerHAndshaker in the Channel attributes and so make it visibile between different handlers.
Result:
Correctly send close frame.
Motivaion:
The HttpHeaders and DefaultHttpHeaders have methods deprecated due to being removed in future releases, but no replacement method to use in the current release. The deprecation policy should not be so aggressive as to not provide any non-deprecated method to use.
Modifications:
- Remove deprecated annotations and javadocs from methods which are the best we can do in terms of matching the master's api for 4.1
Result:
There should be non-deprecated methods available for HttpHeaders in 4.1.
Motivation:
There currently exists http.HttpUtil, http2.HttpUtil, and http.HttpHeaderUtil. Having 2 HttpUtil methods can be confusing and the utilty methods in the http package could be consolidated.
Modifications:
- Rename http2.HttpUtil to http2.HttpConversionUtil
- Move http.HttpHeaderUtil methods into http.HttpUtil
Result:
Consolidated utilities whose names don't overlap.
Fixes https://github.com/netty/netty/issues/4120
Motivation:
The HttpRequestEncoder.encodeInitialLine can now be consistent with the master branch after 85c79dbbe4e6b3e74bd84b3c2eb48fab2916fb6b
Modifications:
- Use the AsciiString and ByteBufUtil.copy methods
Result:
Consistent behavior/code between 4.1 and master branches.
Motivation:
Whe a 100 Continue response was written an IllegalStateException was produced as soon as the user wrote the following response. This regression was introduced by 41b0080fcc8fcace7cd62d238f6a932e79ec8bb1.
Modifications:
- Special handle 100 Continue responses
- Added unit tests
Result:
Fixed regression.
Motivation:
Hixie 76 needs special handling compared to other connection upgrade responses. Our detection code of non websocket responses did actually always use the special handling that only should be used for Hixie 76 responses.
Modifications:
Correctly detect connection upgrade responses which are not for websockets.
Result:
Be able to upgrade connections for other protocols then websockets.
Motivation:
The HTTP schemes defined by https://tools.ietf.org/html/rfc7230 don't have a common representation in Netty.
Modifications:
- Add a class to represent HttpScheme
Result:
The HTTP Scheme is now defined in 1 common location.
Motivation:
The HTTP specification defines specific request-targets in https://tools.ietf.org/html/rfc7230#section-5.3. Netty does not have a way to distinguish between these differnt types, and there is currently no obvious location where these types of methods would live.
Modifications:
- Add methods to distinguish request-targets as defined in https://tools.ietf.org/html/rfc7230#section-5.3
Result:
Common utitlity methods exist to inpsect request-targets.
Motivation:
HttpResponseStatus.reasonPhrase returns an AsciiString, but was compared using equals to a String. Other usages of the reasonPhrase also use the toString() method when not necessary.
Modifications:
- Use the contentEquals method
Result:
Correct comparison, and no toString() when not needed.
Motivation:
The HttpObjectAggregator always responds with a 100-continue response. It should check the Content-Length header to see if the content length is OK, and if not responds with a 417.
Modifications:
- HttpObjectAggregator checks the Content-Length header in the case of a 100-continue.
Result:
HttpObjectAggregator responds with 417 if content is known to be too big.
Motivation:
A degradation in performance has been observed from the 4.0 branch as documented in https://github.com/netty/netty/issues/3962.
Modifications:
- Simplify Headers class hierarchy.
- Restore the DefaultHeaders to be based upon DefaultHttpHeaders from 4.0.
- Make various other modifications that are causing hot spots.
Result:
Performance is now on par with 4.0.
Motivation:
Due not using a cast we insert 32 and not a whitespace into the String.
Modifications:
Correclty cast to char.
Result:
Correct handling of whitespaces.
Motivation:
In the event an HTTP message does not include either a content-length or a transfer-encoding header [RFC 7230](https://tools.ietf.org/html/rfc7230#section-3.3.3) states the behavior must be treated differently for requests and responses. If the channel is half closed then the HttpObjectDecoder is not invoking decodeLast and thus not checking if messages should be sent up the pipeline.
Modifications:
- Add comments to clarify regular decode default case.
- Handle the ChannelInputShutdownEvent in the HttpObjectDecoder and evaluate if messages need to be generated.
Result:
Messages are generated on half closed, and comments clarify existing logic.
Motivation:
We noticed that the headers implementation in Netty for HTTP/2 uses quite a lot of memory
and that also at least the performance of randomly accessing a header is quite poor. The main
concern however was memory usage, as profiling has shown that a DefaultHttp2Headers
not only use a lot of memory it also wastes a lot due to the underlying hashmaps having
to be resized potentially several times as new headers are being inserted.
This is tracked as issue #3600.
Modifications:
We redesigned the DefaultHeaders to simply take a Map object in its constructor and
reimplemented the class using only the Map primitives. That way the implementation
is very concise and hopefully easy to understand and it allows each concrete headers
implementation to provide its own map or to even use a different headers implementation
for processing requests and writing responses i.e. incoming headers need to provide
fast random access while outgoing headers need fast insertion and fast iteration. The
new implementation can support this with hardly any code changes. It also comes
with the advantage that if the Netty project decides to add a third party collections library
as a dependency, one can simply plug in one of those very fast and memory efficient map
implementations and get faster and smaller headers for free.
For now, we are using the JDK's TreeMap for HTTP and HTTP/2 default headers.
Result:
- Significantly fewer lines of code in the implementation. While the total commit is still
roughly 400 lines less, the actual implementation is a lot less. I just added some more
tests and microbenchmarks.
- Overall performance is up. The current implementation should be significantly faster
for insertion and retrieval. However, it is slower when it comes to iteration. There is simply
no way a TreeMap can have the same iteration performance as a linked list (as used in the
current headers implementation). That's totally fine though, because when looking at the
benchmark results @ejona86 pointed out that the performance of the headers is completely
dominated by insertion, that is insertion is so significantly faster in the new implementation
that it does make up for several times the iteration speed. You can't iterate what you haven't
inserted. I am demonstrating that in this spreadsheet [1]. (Actually, iteration performance is
only down for HTTP, it's significantly improved for HTTP/2).
- Memory is down. The implementation with TreeMap uses on avg ~30% less memory. It also does not
produce any garbage while being resized. In load tests for GRPC we have seen a memory reduction
of up to 1.2KB per RPC. I summarized the memory improvements in this spreadsheet [1]. The data
was generated by [2] using JOL.
- While it was my original intend to only improve the memory usage for HTTP/2, it should be similarly
improved for HTTP, SPDY and STOMP as they all share a common implementation.
[1] https://docs.google.com/spreadsheets/d/1ck3RQklyzEcCLlyJoqDXPCWRGVUuS-ArZf0etSXLVDQ/edit#gid=0
[2] https://gist.github.com/buchgr/4458a8bdb51dd58c82b4
Motivation:
The HttpObjectDecoder is on the hot code path for the http codec. There are a few hot methods which can be modified to improve performance.
Modifications:
- Modify AppendableCharSequence to provide unsafe methods which don't need to re-check bounds for every call.
- Update HttpObjectDecoder methods to take advantage of new AppendableCharSequence methods.
Result:
Peformance boost for decoding http objects.
Motivation:
WebSocketServerHandshakerFactory.sendUnsupportedVersionResponse does not
send a LastHttpContent, nor does it flush, and it doesn't send a content
length.
Modifications:
Changed sendUnsupportedVersionResponse to send FullHttpResponse, to
writeAndFlush, and to set a content length of 0. Also added a test for
this method.
Result:
Upstream handlers will be able to determine the end of the response, the
response will actually get written to the client, and the client will be
able to determine the end of the response.
