Mercurial > hg
view hgext/share.py @ 27738:a0e783d26e81
exchange: make clone bundles non-experimental and enabled by default
The clone bundles feature was introduced in Mercurial 3.6 behind an
experimental and disabled by default flag. The feature has been enabled
on hg.mozilla.org for a few months and has served many terabytes of
clones. Users have been encouraged to use the feature and reception
has been very positive (mainly due to faster clones as a result of
connecting to a CDN). I have heard no feedback about changing the
feature other than inquiries about when it will be enabled by default.
So, I think the feature is ready to be enabled by default.
This patch renames experimental.clonebundles to ui.clonebundles,
documents the option, and enables it by default. References to the
experimental state of clone bundles have been removed. The remaining
config option docs in clonebundles.py have been removed because they
are redudant with `hg help config`.
There are some oddities with behavior of clone bundles. Because clones
with clone bundles are effectively 2 `hg pull` operations, there may be
2 transactions. This could result in hooks running twice. If the
subsequent pull is aborted, it could result in partial rollback and an
incomplete clone. This behavior is a bit wonky and should probably
be documented. If this patch is accepted, I'll send a follow-up to
document it. I don't think this behavior should prevent the feature
being enabled by default. Reworking the clone mechanism to support
interrupted or multi-part clones feels like a major new feature and
something that when implemented can change the hook and rollback
semantics of clone bundles. Besides, partial clone is better than
full rollback and hooks running on initial clone are likely rare, so I
think the impact is minimal.
author | Gregory Szorc <gregory.szorc@gmail.com> |
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date | Fri, 08 Jan 2016 10:58:04 -0800 |
parents | 98e59d9e0d77 |
children | f21e0d91d386 |
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# Copyright 2006, 2007 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. '''share a common history between several working directories Automatic Pooled Storage for Clones ----------------------------------- When this extension is active, :hg:`clone` can be configured to automatically share/pool storage across multiple clones. This mode effectively converts :hg:`clone` to :hg:`clone` + :hg:`share`. The benefit of using this mode is the automatic management of store paths and intelligent pooling of related repositories. The following ``share.`` config options influence this feature: ``share.pool`` Filesystem path where shared repository data will be stored. When defined, :hg:`clone` will automatically use shared repository storage instead of creating a store inside each clone. ``share.poolnaming`` How directory names in ``share.pool`` are constructed. "identity" means the name is derived from the first changeset in the repository. In this mode, different remotes share storage if their root/initial changeset is identical. In this mode, the local shared repository is an aggregate of all encountered remote repositories. "remote" means the name is derived from the source repository's path or URL. In this mode, storage is only shared if the path or URL requested in the :hg:`clone` command matches exactly to a repository that was cloned before. The default naming mode is "identity." ''' from mercurial.i18n import _ from mercurial import cmdutil, commands, hg, util, extensions, bookmarks, error from mercurial.hg import repository, parseurl import errno 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' @command('share', [('U', 'noupdate', None, _('do not create a working directory')), ('B', 'bookmarks', None, _('also share bookmarks'))], _('[-U] [-B] SOURCE [DEST]'), norepo=True) def share(ui, source, dest=None, noupdate=False, bookmarks=False): """create a new shared repository Initialize a new repository and working directory that shares its history (and optionally bookmarks) with another repository. .. note:: using rollback or extensions that destroy/modify history (mq, rebase, etc.) can cause considerable confusion with shared clones. In particular, if two shared clones are both updated to the same changeset, and one of them destroys that changeset with rollback, the other clone will suddenly stop working: all operations will fail with "abort: working directory has unknown parent". The only known workaround is to use debugsetparents on the broken clone to reset it to a changeset that still exists. """ return hg.share(ui, source, dest=dest, update=not noupdate, bookmarks=bookmarks) @command('unshare', [], '') def unshare(ui, repo): """convert a shared repository to a normal one Copy the store data to the repo and remove the sharedpath data. """ if not repo.shared(): raise error.Abort(_("this is not a shared repo")) destlock = lock = None lock = repo.lock() try: # we use locks here because if we race with commit, we # can end up with extra data in the cloned revlogs that's # not pointed to by changesets, thus causing verify to # fail destlock = hg.copystore(ui, repo, repo.path) sharefile = repo.join('sharedpath') util.rename(sharefile, sharefile + '.old') repo.requirements.discard('sharedpath') repo._writerequirements() finally: destlock and destlock.release() lock and lock.release() # update store, spath, svfs and sjoin of repo repo.unfiltered().__init__(repo.baseui, repo.root) # Wrap clone command to pass auto share options. def clone(orig, ui, source, *args, **opts): pool = ui.config('share', 'pool', None) if pool: pool = util.expandpath(pool) opts['shareopts'] = dict( pool=pool, mode=ui.config('share', 'poolnaming', 'identity'), ) return orig(ui, source, *args, **opts) def extsetup(ui): extensions.wrapfunction(bookmarks, '_getbkfile', getbkfile) extensions.wrapfunction(bookmarks.bmstore, 'recordchange', recordchange) extensions.wrapfunction(bookmarks.bmstore, '_writerepo', writerepo) extensions.wrapcommand(commands.table, 'clone', clone) def _hassharedbookmarks(repo): """Returns whether this repo has shared bookmarks""" try: shared = repo.vfs.read('shared').splitlines() except IOError as inst: if inst.errno != errno.ENOENT: raise return False return 'bookmarks' in shared def _getsrcrepo(repo): """ Returns the source repository object for a given shared repository. If repo is not a shared repository, return None. """ if repo.sharedpath == repo.path: return None # the sharedpath always ends in the .hg; we want the path to the repo source = repo.vfs.split(repo.sharedpath)[0] srcurl, branches = parseurl(source) return repository(repo.ui, srcurl) def getbkfile(orig, repo): if _hassharedbookmarks(repo): srcrepo = _getsrcrepo(repo) if srcrepo is not None: repo = srcrepo return orig(repo) def recordchange(orig, self, tr): # Continue with write to local bookmarks file as usual orig(self, tr) if _hassharedbookmarks(self._repo): srcrepo = _getsrcrepo(self._repo) if srcrepo is not None: category = 'share-bookmarks' tr.addpostclose(category, lambda tr: self._writerepo(srcrepo)) def writerepo(orig, self, repo): # First write local bookmarks file in case we ever unshare orig(self, repo) if _hassharedbookmarks(self._repo): srcrepo = _getsrcrepo(self._repo) if srcrepo is not None: orig(self, srcrepo)