Gregory Szorc <gregory.szorc@gmail.com> [Mon, 08 Oct 2018 17:00:16 -0700] rev 40133
wireprotov2: send protocol settings frame from client
Now that we have client and server reactor support for protocol
settings and encoding frames, we can start to send them out over
the wire!
This commit teaches the client reactor to send out a protocol
settings frame when needed. The httpv2 peer has been taught to
gather a list of supported content encoders and to advertise them
through the client reactor.
Because the client is now sending new frame types by default, this
constitutes a compatibility break in the framing protocol. The
media type version has been bumped accordingly. This will ensure
existing clients won't attempt to send the new frames to old
servers not supporting this explicit media type. I'm not bothering
with the BC annotation because everything wireprotov2 is highly
experimental and nobody should be running a server yet.
Differential Revision: https://phab.mercurial-scm.org/D4922
Gregory Szorc <gregory.szorc@gmail.com> [Mon, 08 Oct 2018 17:10:59 -0700] rev 40132
wireprotov2: define and use stream encoders
Now that we have basic support for defining stream encoding, it is
time to start doing something with it.
We define various classes implementing stream encoders/decoders for
the defined encoding profiles. This is relatively straightforward.
We teach the inputstream and outputstream classes how to encode,
decode, and flush data.
We then teach the clientreactor how to filter received data through
the inputstream decoder.
One of the features of the framing format is that streams can span
requests. This is a differentiating feature from say HTTP/2, which
associates streams with requests. By allowing streams to span requests,
we can reuse compression context data across requests/responses. But
in order to do this, we need a mechanism to "flush" the encoder at
logical boundaries so that receivers receive all data where it is
expected. And a "flush" event is distinct from a "finish" event from
the perspective of certain compressors because a "flush" will retain
compression context state whereas a "finish" operation will not. This
is why encoders have both a flush() and a finish() and each uses
specific flushing semantics on the underlying compressor.
The added tests verify various behavior of decoders via clientreactor.
These tests do test some compression behavior via use of outputstream.
But for all intents and purposes, server reactor support for encoding
is not yet implemented.
Differential Revision: https://phab.mercurial-scm.org/D4921
Gregory Szorc <gregory.szorc@gmail.com> [Thu, 04 Oct 2018 17:39:16 -0700] rev 40131
wireprotov2: establish dedicated classes for input and output streams
Streams are unidirectional. As part of implementing encoding/decoding
support, it became clear that it didn't make sense for a generic
"stream" class to hold functionality related to both encoding and
decoding. So we create new classes to represent the flavor of
stream.
Differential Revision: https://phab.mercurial-scm.org/D4920
Gregory Szorc <gregory.szorc@gmail.com> [Thu, 04 Oct 2018 17:17:57 -0700] rev 40130
wireprotov2: pass ui into clientreactor and serverreactor
This will allow us to use config options to influence compression
settings.
Differential Revision: https://phab.mercurial-scm.org/D4919