journal: add dirstate tracking
Note that now the default action for `hg journal` is to list the working copy
history, not all bookmarks. In its place is the `--all` switch which lists all
name changes recorded, including the name for which the change was recorded on
each line.
Locking is switched to using a dedicated lock to avoid issues with the dirstate
being written during wlock unlocking (you can't re-lock during that process).
# journal.py
#
# Copyright 2014-2016 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""Track previous positions of bookmarks (EXPERIMENTAL)
This extension adds a new command: `hg journal`, which shows you where
bookmarks were previously located.
"""
from __future__ import absolute_import
import collections
import os
import weakref
from mercurial.i18n import _
from mercurial import (
bookmarks,
cmdutil,
commands,
dirstate,
dispatch,
error,
extensions,
localrepo,
lock,
node,
util,
)
cmdtable = {}
command = cmdutil.command(cmdtable)
# Note for extension authors: ONLY specify testedwith = 'internal' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'internal'
# storage format version; increment when the format changes
storageversion = 0
# namespaces
bookmarktype = 'bookmark'
wdirparenttype = 'wdirparent'
# Journal recording, register hooks and storage object
def extsetup(ui):
extensions.wrapfunction(dispatch, 'runcommand', runcommand)
extensions.wrapfunction(bookmarks.bmstore, '_write', recordbookmarks)
extensions.wrapfunction(
dirstate.dirstate, '_writedirstate', recorddirstateparents)
extensions.wrapfunction(
localrepo.localrepository.dirstate, 'func', wrapdirstate)
def reposetup(ui, repo):
if repo.local():
repo.journal = journalstorage(repo)
def runcommand(orig, lui, repo, cmd, fullargs, *args):
"""Track the command line options for recording in the journal"""
journalstorage.recordcommand(*fullargs)
return orig(lui, repo, cmd, fullargs, *args)
# hooks to record dirstate changes
def wrapdirstate(orig, repo):
"""Make journal storage available to the dirstate object"""
dirstate = orig(repo)
if util.safehasattr(repo, 'journal'):
dirstate.journalstorage = repo.journal
return dirstate
def recorddirstateparents(orig, dirstate, dirstatefp):
"""Records all dirstate parent changes in the journal."""
if util.safehasattr(dirstate, 'journalstorage'):
old = [node.nullid, node.nullid]
nodesize = len(node.nullid)
try:
# The only source for the old state is in the dirstate file still
# on disk; the in-memory dirstate object only contains the new
# state. dirstate._opendirstatefile() switches beteen .hg/dirstate
# and .hg/dirstate.pending depending on the transaction state.
with dirstate._opendirstatefile() as fp:
state = fp.read(2 * nodesize)
if len(state) == 2 * nodesize:
old = [state[:nodesize], state[nodesize:]]
except IOError:
pass
new = dirstate.parents()
if old != new:
# only record two hashes if there was a merge
oldhashes = old[:1] if old[1] == node.nullid else old
newhashes = new[:1] if new[1] == node.nullid else new
dirstate.journalstorage.record(
wdirparenttype, '.', oldhashes, newhashes)
return orig(dirstate, dirstatefp)
# hooks to record bookmark changes (both local and remote)
def recordbookmarks(orig, store, fp):
"""Records all bookmark changes in the journal."""
repo = store._repo
if util.safehasattr(repo, 'journal'):
oldmarks = bookmarks.bmstore(repo)
for mark, value in store.iteritems():
oldvalue = oldmarks.get(mark, node.nullid)
if value != oldvalue:
repo.journal.record(bookmarktype, mark, oldvalue, value)
return orig(store, fp)
class journalentry(collections.namedtuple(
'journalentry',
'timestamp user command namespace name oldhashes newhashes')):
"""Individual journal entry
* timestamp: a mercurial (time, timezone) tuple
* user: the username that ran the command
* namespace: the entry namespace, an opaque string
* name: the name of the changed item, opaque string with meaning in the
namespace
* command: the hg command that triggered this record
* oldhashes: a tuple of one or more binary hashes for the old location
* newhashes: a tuple of one or more binary hashes for the new location
Handles serialisation from and to the storage format. Fields are
separated by newlines, hashes are written out in hex separated by commas,
timestamp and timezone are separated by a space.
"""
@classmethod
def fromstorage(cls, line):
(time, user, command, namespace, name,
oldhashes, newhashes) = line.split('\n')
timestamp, tz = time.split()
timestamp, tz = float(timestamp), int(tz)
oldhashes = tuple(node.bin(hash) for hash in oldhashes.split(','))
newhashes = tuple(node.bin(hash) for hash in newhashes.split(','))
return cls(
(timestamp, tz), user, command, namespace, name,
oldhashes, newhashes)
def __str__(self):
"""String representation for storage"""
time = ' '.join(map(str, self.timestamp))
oldhashes = ','.join([node.hex(hash) for hash in self.oldhashes])
newhashes = ','.join([node.hex(hash) for hash in self.newhashes])
return '\n'.join((
time, self.user, self.command, self.namespace, self.name,
oldhashes, newhashes))
class journalstorage(object):
"""Storage for journal entries
Entries are stored with NUL bytes as separators. See the journalentry
class for the per-entry structure.
The file format starts with an integer version, delimited by a NUL.
This storage uses a dedicated lock; this makes it easier to avoid issues
with adding entries that added when the regular wlock is unlocked (e.g.
the dirstate).
"""
_currentcommand = ()
_lockref = None
def __init__(self, repo):
self.user = util.getuser()
self.ui = repo.ui
self.vfs = repo.vfs
# track the current command for recording in journal entries
@property
def command(self):
commandstr = ' '.join(
map(util.shellquote, journalstorage._currentcommand))
if '\n' in commandstr:
# truncate multi-line commands
commandstr = commandstr.partition('\n')[0] + ' ...'
return commandstr
@classmethod
def recordcommand(cls, *fullargs):
"""Set the current hg arguments, stored with recorded entries"""
# Set the current command on the class because we may have started
# with a non-local repo (cloning for example).
cls._currentcommand = fullargs
def jlock(self):
"""Create a lock for the journal file"""
if self._lockref and self._lockref():
raise error.Abort(_('journal lock does not support nesting'))
desc = _('journal of %s') % self.vfs.base
try:
l = lock.lock(self.vfs, 'journal.lock', 0, desc=desc)
except error.LockHeld as inst:
self.ui.warn(
_("waiting for lock on %s held by %r\n") % (desc, inst.locker))
# default to 600 seconds timeout
l = lock.lock(
self.vfs, 'journal.lock',
int(self.ui.config("ui", "timeout", "600")), desc=desc)
self.ui.warn(_("got lock after %s seconds\n") % l.delay)
self._lockref = weakref.ref(l)
return l
def record(self, namespace, name, oldhashes, newhashes):
"""Record a new journal entry
* namespace: an opaque string; this can be used to filter on the type
of recorded entries.
* name: the name defining this entry; for bookmarks, this is the
bookmark name. Can be filtered on when retrieving entries.
* oldhashes and newhashes: each a single binary hash, or a list of
binary hashes. These represent the old and new position of the named
item.
"""
if not isinstance(oldhashes, list):
oldhashes = [oldhashes]
if not isinstance(newhashes, list):
newhashes = [newhashes]
entry = journalentry(
util.makedate(), self.user, self.command, namespace, name,
oldhashes, newhashes)
with self.jlock():
version = None
# open file in amend mode to ensure it is created if missing
with self.vfs('journal', mode='a+b', atomictemp=True) as f:
f.seek(0, os.SEEK_SET)
# Read just enough bytes to get a version number (up to 2
# digits plus separator)
version = f.read(3).partition('\0')[0]
if version and version != str(storageversion):
# different version of the storage. Exit early (and not
# write anything) if this is not a version we can handle or
# the file is corrupt. In future, perhaps rotate the file
# instead?
self.ui.warn(
_("unsupported journal file version '%s'\n") % version)
return
if not version:
# empty file, write version first
f.write(str(storageversion) + '\0')
f.seek(0, os.SEEK_END)
f.write(str(entry) + '\0')
def filtered(self, namespace=None, name=None):
"""Yield all journal entries with the given namespace or name
Both the namespace and the name are optional; if neither is given all
entries in the journal are produced.
"""
for entry in self:
if namespace is not None and entry.namespace != namespace:
continue
if name is not None and entry.name != name:
continue
yield entry
def __iter__(self):
"""Iterate over the storage
Yields journalentry instances for each contained journal record.
"""
if not self.vfs.exists('journal'):
return
with self.vfs('journal') as f:
raw = f.read()
lines = raw.split('\0')
version = lines and lines[0]
if version != str(storageversion):
version = version or _('not available')
raise error.Abort(_("unknown journal file version '%s'") % version)
# Skip the first line, it's a version number. Reverse the rest.
lines = reversed(lines[1:])
for line in lines:
if not line:
continue
yield journalentry.fromstorage(line)
# journal reading
# log options that don't make sense for journal
_ignoreopts = ('no-merges', 'graph')
@command(
'journal', [
('', 'all', None, 'show history for all names'),
('c', 'commits', None, 'show commit metadata'),
] + [opt for opt in commands.logopts if opt[1] not in _ignoreopts],
'[OPTION]... [BOOKMARKNAME]')
def journal(ui, repo, *args, **opts):
"""show the previous position of bookmarks and the working copy
The journal is used to see the previous commits that bookmarks and the
working copy pointed to. By default the previous locations for the working
copy. Passing a bookmark name will show all the previous positions of
that bookmark. Use the --all switch to show previous locations for all
bookmarks and the working copy; each line will then include the bookmark
name, or '.' for the working copy, as well.
By default hg journal only shows the commit hash and the command that was
running at that time. -v/--verbose will show the prior hash, the user, and
the time at which it happened.
Use -c/--commits to output log information on each commit hash; at this
point you can use the usual `--patch`, `--git`, `--stat` and `--template`
switches to alter the log output for these.
`hg journal -T json` can be used to produce machine readable output.
"""
name = '.'
if opts.get('all'):
if args:
raise error.Abort(
_("You can't combine --all and filtering on a name"))
name = None
if args:
name = args[0]
fm = ui.formatter('journal', opts)
if opts.get("template") != "json":
if name is None:
displayname = _('the working copy and bookmarks')
else:
displayname = "'%s'" % name
ui.status(_("previous locations of %s:\n") % displayname)
limit = cmdutil.loglimit(opts)
entry = None
for count, entry in enumerate(repo.journal.filtered(name=name)):
if count == limit:
break
newhashesstr = ','.join([node.short(hash) for hash in entry.newhashes])
oldhashesstr = ','.join([node.short(hash) for hash in entry.oldhashes])
fm.startitem()
fm.condwrite(ui.verbose, 'oldhashes', '%s -> ', oldhashesstr)
fm.write('newhashes', '%s', newhashesstr)
fm.condwrite(ui.verbose, 'user', ' %-8s', entry.user)
fm.condwrite(opts.get('all'), 'name', ' %-8s', entry.name)
timestring = util.datestr(entry.timestamp, '%Y-%m-%d %H:%M %1%2')
fm.condwrite(ui.verbose, 'date', ' %s', timestring)
fm.write('command', ' %s\n', entry.command)
if opts.get("commits"):
displayer = cmdutil.show_changeset(ui, repo, opts, buffered=False)
for hash in entry.newhashes:
try:
ctx = repo[hash]
displayer.show(ctx)
except error.RepoLookupError as e:
fm.write('repolookuperror', "%s\n\n", str(e))
displayer.close()
fm.end()
if entry is None:
ui.status(_("no recorded locations\n"))