Mercurial > hg-stable
view mercurial/repair.py @ 39646:9c2c77c73f23
wireprotov2: define and implement "changesetdata" command
This commit introduces the "changesetdata" wire protocol command.
The role of the command is to expose data associated with changelog
revisions, including the raw revision data itself.
This command is the first piece of a new clone/pull strategy that
is built on top of domain-specific commands for data retrieval.
Instead of a monolithic "getbundle" command that transfers all of the
things, we'll be introducing commands for fetching specific pieces
of data.
Since the changeset is the fundamental unit from which we derive
pointers to other data (manifests, file nodes, etc), it makes sense
to start reimplementing pull with this data.
The command accepts as arguments a set of root and head revisions
defining the changesets that should be fetched as well as an explicit
list of nodes. By default, the command returns only the node values:
the client must explicitly request additional fields be added to the
response. Current supported fields are the list of parent nodes and
the revision fulltext.
My plan is to eventually add support for transferring other data
associated with changesets, including phases, bookmarks, obsolescence
markers, etc. Since the response format is CBOR, we'll be able to add
this data into the response object relatively easily (it should be
as simple as adding a key in a map).
The documentation captures a number of TODO items. Some of these may
require BC breaking changes. That's fine: wire protocol v2 is still
highly experimental.
Differential Revision: https://phab.mercurial-scm.org/D4481
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Wed, 12 Sep 2018 10:01:16 -0700 |
parents | 73cf21b2e8a6 |
children | 3d22aef3ecd5 |
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# repair.py - functions for repository repair for mercurial # # Copyright 2005, 2006 Chris Mason <mason@suse.com> # Copyright 2007 Matt Mackall # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import errno import hashlib from .i18n import _ from .node import ( hex, short, ) from . import ( bundle2, changegroup, discovery, error, exchange, obsolete, obsutil, pycompat, util, ) from .utils import ( stringutil, ) def backupbundle(repo, bases, heads, node, suffix, compress=True, obsolescence=True): """create a bundle with the specified revisions as a backup""" backupdir = "strip-backup" vfs = repo.vfs if not vfs.isdir(backupdir): vfs.mkdir(backupdir) # Include a hash of all the nodes in the filename for uniqueness allcommits = repo.set('%ln::%ln', bases, heads) allhashes = sorted(c.hex() for c in allcommits) totalhash = hashlib.sha1(''.join(allhashes)).digest() name = "%s/%s-%s-%s.hg" % (backupdir, short(node), hex(totalhash[:4]), suffix) cgversion = changegroup.localversion(repo) comp = None if cgversion != '01': bundletype = "HG20" if compress: comp = 'BZ' elif compress: bundletype = "HG10BZ" else: bundletype = "HG10UN" outgoing = discovery.outgoing(repo, missingroots=bases, missingheads=heads) contentopts = { 'cg.version': cgversion, 'obsolescence': obsolescence, 'phases': True, } return bundle2.writenewbundle(repo.ui, repo, 'strip', name, bundletype, outgoing, contentopts, vfs, compression=comp) def _collectfiles(repo, striprev): """find out the filelogs affected by the strip""" files = set() for x in pycompat.xrange(striprev, len(repo)): files.update(repo[x].files()) return sorted(files) def _collectrevlog(revlog, striprev): _, brokenset = revlog.getstrippoint(striprev) return [revlog.linkrev(r) for r in brokenset] def _collectmanifest(repo, striprev): return _collectrevlog(repo.manifestlog.getstorage(b''), striprev) def _collectbrokencsets(repo, files, striprev): """return the changesets which will be broken by the truncation""" s = set() s.update(_collectmanifest(repo, striprev)) for fname in files: s.update(_collectrevlog(repo.file(fname), striprev)) return s def strip(ui, repo, nodelist, backup=True, topic='backup'): # This function requires the caller to lock the repo, but it operates # within a transaction of its own, and thus requires there to be no current # transaction when it is called. if repo.currenttransaction() is not None: raise error.ProgrammingError('cannot strip from inside a transaction') # Simple way to maintain backwards compatibility for this # argument. if backup in ['none', 'strip']: backup = False repo = repo.unfiltered() repo.destroying() cl = repo.changelog # TODO handle undo of merge sets if isinstance(nodelist, str): nodelist = [nodelist] striplist = [cl.rev(node) for node in nodelist] striprev = min(striplist) files = _collectfiles(repo, striprev) saverevs = _collectbrokencsets(repo, files, striprev) # Some revisions with rev > striprev may not be descendants of striprev. # We have to find these revisions and put them in a bundle, so that # we can restore them after the truncations. # To create the bundle we use repo.changegroupsubset which requires # the list of heads and bases of the set of interesting revisions. # (head = revision in the set that has no descendant in the set; # base = revision in the set that has no ancestor in the set) tostrip = set(striplist) saveheads = set(saverevs) for r in cl.revs(start=striprev + 1): if any(p in tostrip for p in cl.parentrevs(r)): tostrip.add(r) if r not in tostrip: saverevs.add(r) saveheads.difference_update(cl.parentrevs(r)) saveheads.add(r) saveheads = [cl.node(r) for r in saveheads] # compute base nodes if saverevs: descendants = set(cl.descendants(saverevs)) saverevs.difference_update(descendants) savebases = [cl.node(r) for r in saverevs] stripbases = [cl.node(r) for r in tostrip] stripobsidx = obsmarkers = () if repo.ui.configbool('devel', 'strip-obsmarkers'): obsmarkers = obsutil.exclusivemarkers(repo, stripbases) if obsmarkers: stripobsidx = [i for i, m in enumerate(repo.obsstore) if m in obsmarkers] # For a set s, max(parents(s) - s) is the same as max(heads(::s - s)), but # is much faster newbmtarget = repo.revs('max(parents(%ld) - (%ld))', tostrip, tostrip) if newbmtarget: newbmtarget = repo[newbmtarget.first()].node() else: newbmtarget = '.' bm = repo._bookmarks updatebm = [] for m in bm: rev = repo[bm[m]].rev() if rev in tostrip: updatebm.append(m) # create a changegroup for all the branches we need to keep backupfile = None vfs = repo.vfs node = nodelist[-1] if backup: backupfile = backupbundle(repo, stripbases, cl.heads(), node, topic) repo.ui.status(_("saved backup bundle to %s\n") % vfs.join(backupfile)) repo.ui.log("backupbundle", "saved backup bundle to %s\n", vfs.join(backupfile)) tmpbundlefile = None if saveheads: # do not compress temporary bundle if we remove it from disk later # # We do not include obsolescence, it might re-introduce prune markers # we are trying to strip. This is harmless since the stripped markers # are already backed up and we did not touched the markers for the # saved changesets. tmpbundlefile = backupbundle(repo, savebases, saveheads, node, 'temp', compress=False, obsolescence=False) with ui.uninterruptable(): try: with repo.transaction("strip") as tr: offset = len(tr.entries) tr.startgroup() cl.strip(striprev, tr) stripmanifest(repo, striprev, tr, files) for fn in files: repo.file(fn).strip(striprev, tr) tr.endgroup() for i in pycompat.xrange(offset, len(tr.entries)): file, troffset, ignore = tr.entries[i] with repo.svfs(file, 'a', checkambig=True) as fp: fp.truncate(troffset) if troffset == 0: repo.store.markremoved(file) deleteobsmarkers(repo.obsstore, stripobsidx) del repo.obsstore repo.invalidatevolatilesets() repo._phasecache.filterunknown(repo) if tmpbundlefile: ui.note(_("adding branch\n")) f = vfs.open(tmpbundlefile, "rb") gen = exchange.readbundle(ui, f, tmpbundlefile, vfs) if not repo.ui.verbose: # silence internal shuffling chatter repo.ui.pushbuffer() tmpbundleurl = 'bundle:' + vfs.join(tmpbundlefile) txnname = 'strip' if not isinstance(gen, bundle2.unbundle20): txnname = "strip\n%s" % util.hidepassword(tmpbundleurl) with repo.transaction(txnname) as tr: bundle2.applybundle(repo, gen, tr, source='strip', url=tmpbundleurl) if not repo.ui.verbose: repo.ui.popbuffer() f.close() with repo.transaction('repair') as tr: bmchanges = [(m, repo[newbmtarget].node()) for m in updatebm] bm.applychanges(repo, tr, bmchanges) # remove undo files for undovfs, undofile in repo.undofiles(): try: undovfs.unlink(undofile) except OSError as e: if e.errno != errno.ENOENT: ui.warn(_('error removing %s: %s\n') % (undovfs.join(undofile), stringutil.forcebytestr(e))) except: # re-raises if backupfile: ui.warn(_("strip failed, backup bundle stored in '%s'\n") % vfs.join(backupfile)) if tmpbundlefile: ui.warn(_("strip failed, unrecovered changes stored in '%s'\n") % vfs.join(tmpbundlefile)) ui.warn(_("(fix the problem, then recover the changesets with " "\"hg unbundle '%s'\")\n") % vfs.join(tmpbundlefile)) raise else: if tmpbundlefile: # Remove temporary bundle only if there were no exceptions vfs.unlink(tmpbundlefile) repo.destroyed() # return the backup file path (or None if 'backup' was False) so # extensions can use it return backupfile def safestriproots(ui, repo, nodes): """return list of roots of nodes where descendants are covered by nodes""" torev = repo.unfiltered().changelog.rev revs = set(torev(n) for n in nodes) # tostrip = wanted - unsafe = wanted - ancestors(orphaned) # orphaned = affected - wanted # affected = descendants(roots(wanted)) # wanted = revs tostrip = set(repo.revs('%ld-(::((roots(%ld)::)-%ld))', revs, revs, revs)) notstrip = revs - tostrip if notstrip: nodestr = ', '.join(sorted(short(repo[n].node()) for n in notstrip)) ui.warn(_('warning: orphaned descendants detected, ' 'not stripping %s\n') % nodestr) return [c.node() for c in repo.set('roots(%ld)', tostrip)] class stripcallback(object): """used as a transaction postclose callback""" def __init__(self, ui, repo, backup, topic): self.ui = ui self.repo = repo self.backup = backup self.topic = topic or 'backup' self.nodelist = [] def addnodes(self, nodes): self.nodelist.extend(nodes) def __call__(self, tr): roots = safestriproots(self.ui, self.repo, self.nodelist) if roots: strip(self.ui, self.repo, roots, self.backup, self.topic) def delayedstrip(ui, repo, nodelist, topic=None, backup=True): """like strip, but works inside transaction and won't strip irreverent revs nodelist must explicitly contain all descendants. Otherwise a warning will be printed that some nodes are not stripped. Will do a backup if `backup` is True. The last non-None "topic" will be used as the backup topic name. The default backup topic name is "backup". """ tr = repo.currenttransaction() if not tr: nodes = safestriproots(ui, repo, nodelist) return strip(ui, repo, nodes, backup=backup, topic=topic) # transaction postclose callbacks are called in alphabet order. # use '\xff' as prefix so we are likely to be called last. callback = tr.getpostclose('\xffstrip') if callback is None: callback = stripcallback(ui, repo, backup=backup, topic=topic) tr.addpostclose('\xffstrip', callback) if topic: callback.topic = topic callback.addnodes(nodelist) def stripmanifest(repo, striprev, tr, files): revlog = repo.manifestlog.getstorage(b'') revlog.strip(striprev, tr) striptrees(repo, tr, striprev, files) def striptrees(repo, tr, striprev, files): if 'treemanifest' in repo.requirements: # safe but unnecessary # otherwise for unencoded, encoded, size in repo.store.datafiles(): if (unencoded.startswith('meta/') and unencoded.endswith('00manifest.i')): dir = unencoded[5:-12] repo.manifestlog.getstorage(dir).strip(striprev, tr) def rebuildfncache(ui, repo): """Rebuilds the fncache file from repo history. Missing entries will be added. Extra entries will be removed. """ repo = repo.unfiltered() if 'fncache' not in repo.requirements: ui.warn(_('(not rebuilding fncache because repository does not ' 'support fncache)\n')) return with repo.lock(): fnc = repo.store.fncache # Trigger load of fncache. if 'irrelevant' in fnc: pass oldentries = set(fnc.entries) newentries = set() seenfiles = set() progress = ui.makeprogress(_('rebuilding'), unit=_('changesets'), total=len(repo)) for rev in repo: progress.update(rev) ctx = repo[rev] for f in ctx.files(): # This is to minimize I/O. if f in seenfiles: continue seenfiles.add(f) i = 'data/%s.i' % f d = 'data/%s.d' % f if repo.store._exists(i): newentries.add(i) if repo.store._exists(d): newentries.add(d) progress.complete() if 'treemanifest' in repo.requirements: # safe but unnecessary otherwise for dir in util.dirs(seenfiles): i = 'meta/%s/00manifest.i' % dir d = 'meta/%s/00manifest.d' % dir if repo.store._exists(i): newentries.add(i) if repo.store._exists(d): newentries.add(d) addcount = len(newentries - oldentries) removecount = len(oldentries - newentries) for p in sorted(oldentries - newentries): ui.write(_('removing %s\n') % p) for p in sorted(newentries - oldentries): ui.write(_('adding %s\n') % p) if addcount or removecount: ui.write(_('%d items added, %d removed from fncache\n') % (addcount, removecount)) fnc.entries = newentries fnc._dirty = True with repo.transaction('fncache') as tr: fnc.write(tr) else: ui.write(_('fncache already up to date\n')) def deleteobsmarkers(obsstore, indices): """Delete some obsmarkers from obsstore and return how many were deleted 'indices' is a list of ints which are the indices of the markers to be deleted. Every invocation of this function completely rewrites the obsstore file, skipping the markers we want to be removed. The new temporary file is created, remaining markers are written there and on .close() this file gets atomically renamed to obsstore, thus guaranteeing consistency.""" if not indices: # we don't want to rewrite the obsstore with the same content return left = [] current = obsstore._all n = 0 for i, m in enumerate(current): if i in indices: n += 1 continue left.append(m) newobsstorefile = obsstore.svfs('obsstore', 'w', atomictemp=True) for bytes in obsolete.encodemarkers(left, True, obsstore._version): newobsstorefile.write(bytes) newobsstorefile.close() return n