view tests/test-journal.t @ 39561:d06834e0f48e

wireprotov2peer: stream decoded responses

Previously, wire protocol version 2 would buffer all response data.
Only once all data was received did we CBOR decode it and resolve
the future associated with the command. This was obviously not
desirable. In future commits that introduce large response payloads,
this caused significant memory bloat and slowed down client
operations due to waiting on the server.

This commit refactors the response handling code so that response
data can be streamed.

Command response objects now contain a buffered CBOR decoder. As
new data arrives, it is fed into the decoder. Decoded objects are
made available to the generator as they are decoded.

Because there is a separate thread processing incoming frames and
feeding data into the response object, there is the potential for
race conditions when mutating response objects. So a lock has been
added to guard access to critical state variables.

Because the generator emitting decoded objects needs to wait on
those objects to become available, we've added an Event for the
generator to wait on so it doesn't busy loop. This does mean
there is the potential for deadlocks. And I'm pretty sure they can
occur in some scenarios. We already have a handful of TODOs around
this. But I've added some more. Fixing this will likely require
moving the background thread receiving frames into clienthandler.
We likely would have done this anyway when implementing the client
bits for the SSH transport.

Test output changes because the initial CBOR map holding the overall
response state is now always handled internally by the response
object.

Differential Revision: https://phab.mercurial-scm.org/D4474

Tests for the journal extension; records bookmark locations.

  $ cat >> testmocks.py << EOF
  > # mock out procutil.getuser() and util.makedate() to supply testable values
  > import os
  > from mercurial import util, pycompat
  > from mercurial.utils import dateutil, procutil
  > def mockgetuser():
  >     return b'foobar'
  > 
  > def mockmakedate():
  >     filename = os.path.join(os.environ['TESTTMP'], 'testtime')
  >     try:
  >         with open(filename, 'rb') as timef:
  >             time = float(timef.read()) + 1
  >     except IOError:
  >         time = 0.0
  >     with open(filename, 'wb') as timef:
  >         timef.write(pycompat.bytestr(time))
  >     return (time, 0)
  > 
  > procutil.getuser = mockgetuser
  > dateutil.makedate = mockmakedate
  > EOF

  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > journal=
  > testmocks=`pwd`/testmocks.py
  > EOF

Setup repo

  $ hg init repo
  $ cd repo

Test empty journal

  $ hg journal
  previous locations of '.':
  no recorded locations
  $ hg journal foo
  previous locations of 'foo':
  no recorded locations

Test that working copy changes are tracked

  $ echo a > a
  $ hg commit -Aqm a
  $ hg journal
  previous locations of '.':
  cb9a9f314b8b  commit -Aqm a
  $ echo b > a
  $ hg commit -Aqm b
  $ hg journal
  previous locations of '.':
  1e6c11564562  commit -Aqm b
  cb9a9f314b8b  commit -Aqm a
  $ hg up 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg journal
  previous locations of '.':
  cb9a9f314b8b  up 0
  1e6c11564562  commit -Aqm b
  cb9a9f314b8b  commit -Aqm a

Test that bookmarks are tracked

  $ hg book -r tip bar
  $ hg journal bar
  previous locations of 'bar':
  1e6c11564562  book -r tip bar
  $ hg book -f bar
  $ hg journal bar
  previous locations of 'bar':
  cb9a9f314b8b  book -f bar
  1e6c11564562  book -r tip bar
  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updating bookmark bar
  $ hg journal bar
  previous locations of 'bar':
  1e6c11564562  up
  cb9a9f314b8b  book -f bar
  1e6c11564562  book -r tip bar

Test that bookmarks and working copy tracking is not mixed

  $ hg journal
  previous locations of '.':
  1e6c11564562  up
  cb9a9f314b8b  up 0
  1e6c11564562  commit -Aqm b
  cb9a9f314b8b  commit -Aqm a

Test that you can list all entries as well as limit the list or filter on them

  $ hg book -r tip baz
  $ hg journal --all
  previous locations of the working copy and bookmarks:
  1e6c11564562  baz       book -r tip baz
  1e6c11564562  bar       up
  1e6c11564562  .         up
  cb9a9f314b8b  bar       book -f bar
  1e6c11564562  bar       book -r tip bar
  cb9a9f314b8b  .         up 0
  1e6c11564562  .         commit -Aqm b
  cb9a9f314b8b  .         commit -Aqm a
  $ hg journal --limit 2
  previous locations of '.':
  1e6c11564562  up
  cb9a9f314b8b  up 0
  $ hg journal bar
  previous locations of 'bar':
  1e6c11564562  up
  cb9a9f314b8b  book -f bar
  1e6c11564562  book -r tip bar
  $ hg journal foo
  previous locations of 'foo':
  no recorded locations
  $ hg journal .
  previous locations of '.':
  1e6c11564562  up
  cb9a9f314b8b  up 0
  1e6c11564562  commit -Aqm b
  cb9a9f314b8b  commit -Aqm a
  $ hg journal "re:ba."
  previous locations of 're:ba.':
  1e6c11564562  baz       book -r tip baz
  1e6c11564562  bar       up
  cb9a9f314b8b  bar       book -f bar
  1e6c11564562  bar       book -r tip bar

Test that verbose, JSON, template and commit output work

  $ hg journal --verbose --all
  previous locations of the working copy and bookmarks:
  000000000000 -> 1e6c11564562 foobar    baz      1970-01-01 00:00 +0000  book -r tip baz
  cb9a9f314b8b -> 1e6c11564562 foobar    bar      1970-01-01 00:00 +0000  up
  cb9a9f314b8b -> 1e6c11564562 foobar    .        1970-01-01 00:00 +0000  up
  1e6c11564562 -> cb9a9f314b8b foobar    bar      1970-01-01 00:00 +0000  book -f bar
  000000000000 -> 1e6c11564562 foobar    bar      1970-01-01 00:00 +0000  book -r tip bar
  1e6c11564562 -> cb9a9f314b8b foobar    .        1970-01-01 00:00 +0000  up 0
  cb9a9f314b8b -> 1e6c11564562 foobar    .        1970-01-01 00:00 +0000  commit -Aqm b
  000000000000 -> cb9a9f314b8b foobar    .        1970-01-01 00:00 +0000  commit -Aqm a
  $ hg journal --verbose -Tjson
  [
   {
    "command": "up",
    "date": [5, 0],
    "name": ".",
    "newhashes": ["1e6c11564562b4ed919baca798bc4338bd299d6a"],
    "oldhashes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"],
    "user": "foobar"
   },
   {
    "command": "up 0",
    "date": [2, 0],
    "name": ".",
    "newhashes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"],
    "oldhashes": ["1e6c11564562b4ed919baca798bc4338bd299d6a"],
    "user": "foobar"
   },
   {
    "command": "commit -Aqm b",
    "date": [1, 0],
    "name": ".",
    "newhashes": ["1e6c11564562b4ed919baca798bc4338bd299d6a"],
    "oldhashes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"],
    "user": "foobar"
   },
   {
    "command": "commit -Aqm a",
    "date": [0, 0],
    "name": ".",
    "newhashes": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"],
    "oldhashes": ["0000000000000000000000000000000000000000"],
    "user": "foobar"
   }
  ]

  $ cat <<EOF >> $HGRCPATH
  > [templates]
  > j = "{oldhashes % '{node|upper}'} -> {newhashes % '{node|upper}'}
  >      - user: {user}
  >      - command: {command}
  >      - date: {date|rfc3339date}
  >      - newhashes: {newhashes}
  >      - oldhashes: {oldhashes}
  >      "
  > EOF
  $ hg journal -Tj -l1
  previous locations of '.':
  CB9A9F314B8B07BA71012FCDBC544B5A4D82FF5B -> 1E6C11564562B4ED919BACA798BC4338BD299D6A
  - user: foobar
  - command: up
  - date: 1970-01-01T00:00:05+00:00
  - newhashes: 1e6c11564562b4ed919baca798bc4338bd299d6a
  - oldhashes: cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b

  $ hg journal --commit
  previous locations of '.':
  1e6c11564562  up
  changeset:   1:1e6c11564562
  bookmark:    bar
  bookmark:    baz
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     b
  
  cb9a9f314b8b  up 0
  changeset:   0:cb9a9f314b8b
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     a
  
  1e6c11564562  commit -Aqm b
  changeset:   1:1e6c11564562
  bookmark:    bar
  bookmark:    baz
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     b
  
  cb9a9f314b8b  commit -Aqm a
  changeset:   0:cb9a9f314b8b
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     a
  

Test for behaviour on unexpected storage version information

  $ printf '42\0' > .hg/namejournal
  $ hg journal
  previous locations of '.':
  abort: unknown journal file version '42'
  [255]
  $ hg book -r tip doomed
  unsupported journal file version '42'