Motivation:
Draft 12 has just arrived and has quite a few changes. Need to update in
order to keep current with the spec.
Modifications:
This is a rewrite of the original (draft 10) code. There are only 2
handlers now: preface and connection. The connection handler is now
callback based rather than frame based (there are no frame classes
anymore). AbstractHttp2ConnectionHandler is the base class for any
HTTP/2 handlers. All of the stream priority logic now resides in the
outbound flow controller, and its interface exposes methods for
adding/updating priority for streams.
Upgraded to hpack 0.7.0, which is used by draft12. Also removed
draft10 code and moved draft12 code to the ../http2 package
(no draft subpackage).
Result:
Addition of a HTTP/2 draft 12 support.
Motivation:
See: https://github.com/netty/netty/issues/2402
See: https://tools.ietf.org/html/draft-ietf-httpbis-http2-10#section-3.5
Only the client should send the preface string, the server should not.
"The server connection header consists of just a SETTINGS frame (Section 6.5)
that MUST be the first frame the server sends in the HTTP/2 connection."
Modifications:
Split out Http2ClientPrefaceWriter and Http2ServerPrefaceReader from
Http2FrameEncoder and Http2FrameDecoder. The new channel handlers are added
to the pipeline and remove themselves after the preface is written/read.
Result:
HTTP2 client sends preface, server does not, in compliance with spec.
Motivation:
HTTP2 is generally negotiated over SSL, makes more sense to provide an SSL example.
Modifications:
Copy the SDPY example to add SSL and NPN negotiation to the HTTP2 example.
Result:
Http2Server and Http2Client examples use SSL.
and initial settings frame were sent.
Motivation:
The current logic for marking the connection header and initial settings
frame is a bit complicated.
Modifications:
- Http2FrameEncoder, Http2ConnectionHandler: removed sent listeners and
set the sent flag immediately.
Result:
Just a code cleanup ... behavior is the same.
Motivation:
The current HTTP/2 support does not properly comply with the HTTP/2 spec
wrt startup.
Modifications:
Changed the frame codec as well as the connection handler to support
exchange of the connection preface, followed immediately by an initial
settings frame.
Result:
The HTTP/2 initialization handshake will be in compliance with the spec.
Will need more work to support the upgrade protocols, however :)
Motivation:
Provide some example code to show how to bootstrap client and server for
use with HTTP/2 framing.
Modifications:
- Fixed Http2ConnectionHandler to allow headers after stream creation.
Needed for response headers.
- Added toString() to all frame classes to help with debugging/logging
- Added example classes for HTTP/2
Result:
HTTP/2 connections now properly support response headers. Examples for
HTTP/2 provided with the distribution of examples module.
After your change, what will change.
Motivation:
Bring the http2 codec more inline with the rest of Netty's code-base.
Modifications:
- Add null checks in constructors
- Move private static methods into inner-classes where they are used
- Use getBytes(CharsetUtil.UTf8)
Result:
More consistent code-base
Motivation:
The use of the guava library library is fairly superficial and can
easily be removed to reduce the overall dependency list of the module.
Cleaning up the HTTP2 code to use common Netty utilities, etc.
Modifications:
- Various changes to remove use of guava preconditions and collections.
- Changed default charset to use CharsetUtil.UTF_8.
- Changed StreamState to use ArrayDeque instead of LinkedList.
- Changed precondition checks to throw NPE
- Changed implementation of Http2Headers to more closely mirror the SPDY
implementation.
Result:
The behavior of the HTTP2 module will remain unchanged.
Motivation:
Needed a rough performance comparison between SPDY and HTTP 2.0 framing.
Expected performance gains were seen in HTTP 2.0 due to header
compression.
Modifications:
Added a new codec-http2 module containing all of the new source and unit
tests. Updated the top-level pom.xml to add this as a child module.
Result:
Netty will have basic support for HTTP2.
