wireproto: implement basic frame reading and processing
We just implemented support for writing frames. Now let's implement
support for reading them.
The bulk of the new code is for a class that maintains the state of
a server. Essentially, you construct an instance, feed frames to it,
and it tells you what you should do next. The design is inspired by
the "sans I/O" movement and the reactor pattern. We don't want to
perform I/O or any major blocking event during frame ingestion because
this arbitrarily limits ways that server pieces can be implemented.
For example, it makes it much harder to swap in an alternate
implementation based on asyncio or do crazy things like have requests
dispatch to other processes.
We do still implement readframe() which does I/O. But it is decoupled
from the server reactor. And important parsing of frame headers is
a standalone function. So I/O is only needed to obtain frame data.
Because testing server-side ingest is useful and difficult on running
servers, we create a new "debugreflect" endpoint that will echo back
to the client what was received and how it was interpreted. This could
be useful for a server admin, someone implementing a client. But
immediately, it is useful for testing: we're able to demonstrate that
frames are parsed correctly and turned into requests to run commands
without having to implement command dispatch on the server!
In addition, we implement Python level unit tests for the reactor.
This is vastly more efficient than sending requests to the
"debugreflect" endpoint and vastly more powerful for advanced
testing.
Differential Revision: https://phab.mercurial-scm.org/D2852
============================================
Testing obsolescence markers push: Cases A.2
============================================
Mercurial pushes obsolescences markers relevant to the "pushed-set", the set of
all changesets that requested to be "in sync" after the push (even if they are
already on both side).
This test belongs to a series of tests checking such set is properly computed
and applied. This does not tests "obsmarkers" discovery capabilities.
Category A: simple cases
TestCase 2: Two heads, only one of them pushed
A.2 Two heads, only on of then pushed
=====================================
.. {{{
.. ⇠○ B
.. ⇠◔ | A
.. |/
.. ● O
.. }}}
..
.. Markers exist from:
..
.. * A
.. * B
..
..
.. Command runs:
..
.. * hg push -r A
..
.. Expected exchange:
..
.. * chain from A
..
.. Expected Exclude:
..
.. * chain from B
Setup
-----
$ . $TESTDIR/testlib/exchange-obsmarker-util.sh
initial
$ setuprepos A.2
creating test repo for test case A.2
- pulldest
- main
- pushdest
cd into `main` and proceed with env setup
$ cd main
$ mkcommit A
$ hg debugobsolete aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa `getid 'desc(A)'`
$ hg up '.~1'
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkcommit B
created new head
$ hg debugobsolete bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb `getid 'desc(B)'`
$ hg log -G
@ 35b183996678 (draft): B
|
| o f5bc6836db60 (draft): A
|/
o a9bdc8b26820 (public): O
$ inspect_obsmarkers
obsstore content
================
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 35b1839966785d5703a01607229eea932db42f87 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
$ cd ..
$ cd ..
Actual Test
-----------
$ dotest A.2 A
## Running testcase A.2
# testing echange of "A" (f5bc6836db60)
## initial state
# obstore: main
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 35b1839966785d5703a01607229eea932db42f87 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
# obstore: pushdest
# obstore: pulldest
## pushing "A" from main to pushdest
pushing to pushdest
searching for changes
remote: adding changesets
remote: adding manifests
remote: adding file changes
remote: added 1 changesets with 1 changes to 1 files
remote: 1 new obsolescence markers
## post push state
# obstore: main
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 35b1839966785d5703a01607229eea932db42f87 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
# obstore: pushdest
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
# obstore: pulldest
## pulling "f5bc6836db60" from main into pulldest
pulling from main
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
1 new obsolescence markers
new changesets f5bc6836db60
(run 'hg update' to get a working copy)
## post pull state
# obstore: main
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 35b1839966785d5703a01607229eea932db42f87 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
# obstore: pushdest
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
# obstore: pulldest
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa f5bc6836db60e308a17ba08bf050154ba9c4fad7 0 (Thu Jan 01 00:00:00 1970 +0000) {'user': 'test'}
$ cd ..