manifest: add some documentation to _lazymanifest python code
It was not particularly easy figuring out the design of this class and keeping
track of how the pieces work. So might as well write some of it down for the
next person.
# bundlerepo.py - repository class for viewing uncompressed bundles
#
# Copyright 2006, 2007 Benoit Boissinot <bboissin@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""Repository class for viewing uncompressed bundles.
This provides a read-only repository interface to bundles as if they
were part of the actual repository.
"""
from __future__ import absolute_import
import os
import shutil
from .i18n import _
from .node import nullid
from . import (
bundle2,
changegroup,
changelog,
cmdutil,
discovery,
encoding,
error,
exchange,
filelog,
localrepo,
manifest,
mdiff,
node as nodemod,
pathutil,
phases,
pycompat,
revlog,
util,
vfs as vfsmod,
)
class bundlerevlog(revlog.revlog):
def __init__(self, opener, indexfile, cgunpacker, linkmapper):
# How it works:
# To retrieve a revision, we need to know the offset of the revision in
# the bundle (an unbundle object). We store this offset in the index
# (start). The base of the delta is stored in the base field.
#
# To differentiate a rev in the bundle from a rev in the revlog, we
# check revision against repotiprev.
opener = vfsmod.readonlyvfs(opener)
revlog.revlog.__init__(self, opener, indexfile)
self.bundle = cgunpacker
n = len(self)
self.repotiprev = n - 1
self.bundlerevs = set() # used by 'bundle()' revset expression
for deltadata in cgunpacker.deltaiter():
node, p1, p2, cs, deltabase, delta, flags = deltadata
size = len(delta)
start = cgunpacker.tell() - size
link = linkmapper(cs)
if node in self.nodemap:
# this can happen if two branches make the same change
self.bundlerevs.add(self.nodemap[node])
continue
for p in (p1, p2):
if p not in self.nodemap:
raise error.LookupError(p, self.indexfile,
_("unknown parent"))
if deltabase not in self.nodemap:
raise LookupError(deltabase, self.indexfile,
_('unknown delta base'))
baserev = self.rev(deltabase)
# start, size, full unc. size, base (unused), link, p1, p2, node
e = (revlog.offset_type(start, flags), size, -1, baserev, link,
self.rev(p1), self.rev(p2), node)
self.index.append(e)
self.nodemap[node] = n
self.bundlerevs.add(n)
n += 1
def _chunk(self, rev, df=None):
# Warning: in case of bundle, the diff is against what we stored as
# delta base, not against rev - 1
# XXX: could use some caching
if rev <= self.repotiprev:
return revlog.revlog._chunk(self, rev)
self.bundle.seek(self.start(rev))
return self.bundle.read(self.length(rev))
def revdiff(self, rev1, rev2):
"""return or calculate a delta between two revisions"""
if rev1 > self.repotiprev and rev2 > self.repotiprev:
# hot path for bundle
revb = self.index[rev2][3]
if revb == rev1:
return self._chunk(rev2)
elif rev1 <= self.repotiprev and rev2 <= self.repotiprev:
return revlog.revlog.revdiff(self, rev1, rev2)
return mdiff.textdiff(self.revision(rev1, raw=True),
self.revision(rev2, raw=True))
def revision(self, nodeorrev, _df=None, raw=False):
"""return an uncompressed revision of a given node or revision
number.
"""
if isinstance(nodeorrev, int):
rev = nodeorrev
node = self.node(rev)
else:
node = nodeorrev
rev = self.rev(node)
if node == nullid:
return ""
rawtext = None
chain = []
iterrev = rev
# reconstruct the revision if it is from a changegroup
while iterrev > self.repotiprev:
if self._revisioncache and self._revisioncache[1] == iterrev:
rawtext = self._revisioncache[2]
break
chain.append(iterrev)
iterrev = self.index[iterrev][3]
if rawtext is None:
rawtext = self.baserevision(iterrev)
while chain:
delta = self._chunk(chain.pop())
rawtext = mdiff.patches(rawtext, [delta])
text, validatehash = self._processflags(rawtext, self.flags(rev),
'read', raw=raw)
if validatehash:
self.checkhash(text, node, rev=rev)
self._revisioncache = (node, rev, rawtext)
return text
def baserevision(self, nodeorrev):
# Revlog subclasses may override 'revision' method to modify format of
# content retrieved from revlog. To use bundlerevlog with such class one
# needs to override 'baserevision' and make more specific call here.
return revlog.revlog.revision(self, nodeorrev, raw=True)
def addrevision(self, *args, **kwargs):
raise NotImplementedError
def addgroup(self, *args, **kwargs):
raise NotImplementedError
def strip(self, *args, **kwargs):
raise NotImplementedError
def checksize(self):
raise NotImplementedError
class bundlechangelog(bundlerevlog, changelog.changelog):
def __init__(self, opener, cgunpacker):
changelog.changelog.__init__(self, opener)
linkmapper = lambda x: x
bundlerevlog.__init__(self, opener, self.indexfile, cgunpacker,
linkmapper)
def baserevision(self, nodeorrev):
# Although changelog doesn't override 'revision' method, some extensions
# may replace this class with another that does. Same story with
# manifest and filelog classes.
# This bypasses filtering on changelog.node() and rev() because we need
# revision text of the bundle base even if it is hidden.
oldfilter = self.filteredrevs
try:
self.filteredrevs = ()
return changelog.changelog.revision(self, nodeorrev, raw=True)
finally:
self.filteredrevs = oldfilter
class bundlemanifest(bundlerevlog, manifest.manifestrevlog):
def __init__(self, opener, cgunpacker, linkmapper, dirlogstarts=None,
dir=''):
manifest.manifestrevlog.__init__(self, opener, tree=dir)
bundlerevlog.__init__(self, opener, self.indexfile, cgunpacker,
linkmapper)
if dirlogstarts is None:
dirlogstarts = {}
if self.bundle.version == "03":
dirlogstarts = _getfilestarts(self.bundle)
self._dirlogstarts = dirlogstarts
self._linkmapper = linkmapper
def baserevision(self, nodeorrev):
node = nodeorrev
if isinstance(node, int):
node = self.node(node)
if node in self.fulltextcache:
result = '%s' % self.fulltextcache[node]
else:
result = manifest.manifestrevlog.revision(self, nodeorrev, raw=True)
return result
def dirlog(self, d):
if d in self._dirlogstarts:
self.bundle.seek(self._dirlogstarts[d])
return bundlemanifest(
self.opener, self.bundle, self._linkmapper,
self._dirlogstarts, dir=d)
return super(bundlemanifest, self).dirlog(d)
class bundlefilelog(filelog.filelog):
def __init__(self, opener, path, cgunpacker, linkmapper):
filelog.filelog.__init__(self, opener, path)
self._revlog = bundlerevlog(opener, self.indexfile,
cgunpacker, linkmapper)
def baserevision(self, nodeorrev):
return filelog.filelog.revision(self, nodeorrev, raw=True)
class bundlepeer(localrepo.localpeer):
def canpush(self):
return False
class bundlephasecache(phases.phasecache):
def __init__(self, *args, **kwargs):
super(bundlephasecache, self).__init__(*args, **kwargs)
if util.safehasattr(self, 'opener'):
self.opener = vfsmod.readonlyvfs(self.opener)
def write(self):
raise NotImplementedError
def _write(self, fp):
raise NotImplementedError
def _updateroots(self, phase, newroots, tr):
self.phaseroots[phase] = newroots
self.invalidate()
self.dirty = True
def _getfilestarts(cgunpacker):
filespos = {}
for chunkdata in iter(cgunpacker.filelogheader, {}):
fname = chunkdata['filename']
filespos[fname] = cgunpacker.tell()
for chunk in iter(lambda: cgunpacker.deltachunk(None), {}):
pass
return filespos
class bundlerepository(object):
"""A repository instance that is a union of a local repo and a bundle.
Instances represent a read-only repository composed of a local repository
with the contents of a bundle file applied. The repository instance is
conceptually similar to the state of a repository after an
``hg unbundle`` operation. However, the contents of the bundle are never
applied to the actual base repository.
Instances constructed directly are not usable as repository objects.
Use instance() or makebundlerepository() to create instances.
"""
def __init__(self, bundlepath, url, tempparent):
self._tempparent = tempparent
self._url = url
self.ui.setconfig('phases', 'publish', False, 'bundlerepo')
self.tempfile = None
f = util.posixfile(bundlepath, "rb")
bundle = exchange.readbundle(self.ui, f, bundlepath)
if isinstance(bundle, bundle2.unbundle20):
self._bundlefile = bundle
self._cgunpacker = None
cgpart = None
for part in bundle.iterparts(seekable=True):
if part.type == 'changegroup':
if cgpart:
raise NotImplementedError("can't process "
"multiple changegroups")
cgpart = part
self._handlebundle2part(bundle, part)
if not cgpart:
raise error.Abort(_("No changegroups found"))
# This is required to placate a later consumer, which expects
# the payload offset to be at the beginning of the changegroup.
# We need to do this after the iterparts() generator advances
# because iterparts() will seek to end of payload after the
# generator returns control to iterparts().
cgpart.seek(0, os.SEEK_SET)
elif isinstance(bundle, changegroup.cg1unpacker):
if bundle.compressed():
f = self._writetempbundle(bundle.read, '.hg10un',
header='HG10UN')
bundle = exchange.readbundle(self.ui, f, bundlepath, self.vfs)
self._bundlefile = bundle
self._cgunpacker = bundle
else:
raise error.Abort(_('bundle type %s cannot be read') %
type(bundle))
# dict with the mapping 'filename' -> position in the changegroup.
self._cgfilespos = {}
self.firstnewrev = self.changelog.repotiprev + 1
phases.retractboundary(self, None, phases.draft,
[ctx.node() for ctx in self[self.firstnewrev:]])
def _handlebundle2part(self, bundle, part):
if part.type != 'changegroup':
return
cgstream = part
version = part.params.get('version', '01')
legalcgvers = changegroup.supportedincomingversions(self)
if version not in legalcgvers:
msg = _('Unsupported changegroup version: %s')
raise error.Abort(msg % version)
if bundle.compressed():
cgstream = self._writetempbundle(part.read, '.cg%sun' % version)
self._cgunpacker = changegroup.getunbundler(version, cgstream, 'UN')
def _writetempbundle(self, readfn, suffix, header=''):
"""Write a temporary file to disk
"""
fdtemp, temp = self.vfs.mkstemp(prefix="hg-bundle-",
suffix=suffix)
self.tempfile = temp
with os.fdopen(fdtemp, r'wb') as fptemp:
fptemp.write(header)
while True:
chunk = readfn(2**18)
if not chunk:
break
fptemp.write(chunk)
return self.vfs.open(self.tempfile, mode="rb")
@localrepo.unfilteredpropertycache
def _phasecache(self):
return bundlephasecache(self, self._phasedefaults)
@localrepo.unfilteredpropertycache
def changelog(self):
# consume the header if it exists
self._cgunpacker.changelogheader()
c = bundlechangelog(self.svfs, self._cgunpacker)
self.manstart = self._cgunpacker.tell()
return c
@localrepo.unfilteredpropertycache
def manifestlog(self):
self._cgunpacker.seek(self.manstart)
# consume the header if it exists
self._cgunpacker.manifestheader()
linkmapper = self.unfiltered().changelog.rev
rootstore = bundlemanifest(self.svfs, self._cgunpacker, linkmapper)
self.filestart = self._cgunpacker.tell()
return manifest.manifestlog(self.svfs, self, rootstore,
self.narrowmatch())
def _consumemanifest(self):
"""Consumes the manifest portion of the bundle, setting filestart so the
file portion can be read."""
self._cgunpacker.seek(self.manstart)
self._cgunpacker.manifestheader()
for delta in self._cgunpacker.deltaiter():
pass
self.filestart = self._cgunpacker.tell()
@localrepo.unfilteredpropertycache
def manstart(self):
self.changelog
return self.manstart
@localrepo.unfilteredpropertycache
def filestart(self):
self.manifestlog
# If filestart was not set by self.manifestlog, that means the
# manifestlog implementation did not consume the manifests from the
# changegroup (ex: it might be consuming trees from a separate bundle2
# part instead). So we need to manually consume it.
if r'filestart' not in self.__dict__:
self._consumemanifest()
return self.filestart
def url(self):
return self._url
def file(self, f):
if not self._cgfilespos:
self._cgunpacker.seek(self.filestart)
self._cgfilespos = _getfilestarts(self._cgunpacker)
if f in self._cgfilespos:
self._cgunpacker.seek(self._cgfilespos[f])
linkmapper = self.unfiltered().changelog.rev
return bundlefilelog(self.svfs, f, self._cgunpacker, linkmapper)
else:
return super(bundlerepository, self).file(f)
def close(self):
"""Close assigned bundle file immediately."""
self._bundlefile.close()
if self.tempfile is not None:
self.vfs.unlink(self.tempfile)
if self._tempparent:
shutil.rmtree(self._tempparent, True)
def cancopy(self):
return False
def peer(self):
return bundlepeer(self)
def getcwd(self):
return encoding.getcwd() # always outside the repo
# Check if parents exist in localrepo before setting
def setparents(self, p1, p2=nullid):
p1rev = self.changelog.rev(p1)
p2rev = self.changelog.rev(p2)
msg = _("setting parent to node %s that only exists in the bundle\n")
if self.changelog.repotiprev < p1rev:
self.ui.warn(msg % nodemod.hex(p1))
if self.changelog.repotiprev < p2rev:
self.ui.warn(msg % nodemod.hex(p2))
return super(bundlerepository, self).setparents(p1, p2)
def instance(ui, path, create, intents=None, createopts=None):
if create:
raise error.Abort(_('cannot create new bundle repository'))
# internal config: bundle.mainreporoot
parentpath = ui.config("bundle", "mainreporoot")
if not parentpath:
# try to find the correct path to the working directory repo
parentpath = cmdutil.findrepo(encoding.getcwd())
if parentpath is None:
parentpath = ''
if parentpath:
# Try to make the full path relative so we get a nice, short URL.
# In particular, we don't want temp dir names in test outputs.
cwd = encoding.getcwd()
if parentpath == cwd:
parentpath = ''
else:
cwd = pathutil.normasprefix(cwd)
if parentpath.startswith(cwd):
parentpath = parentpath[len(cwd):]
u = util.url(path)
path = u.localpath()
if u.scheme == 'bundle':
s = path.split("+", 1)
if len(s) == 1:
repopath, bundlename = parentpath, s[0]
else:
repopath, bundlename = s
else:
repopath, bundlename = parentpath, path
return makebundlerepository(ui, repopath, bundlename)
def makebundlerepository(ui, repopath, bundlepath):
"""Make a bundle repository object based on repo and bundle paths."""
if repopath:
url = 'bundle:%s+%s' % (util.expandpath(repopath), bundlepath)
else:
url = 'bundle:%s' % bundlepath
# Because we can't make any guarantees about the type of the base
# repository, we can't have a static class representing the bundle
# repository. We also can't make any guarantees about how to even
# call the base repository's constructor!
#
# So, our strategy is to go through ``localrepo.instance()`` to construct
# a repo instance. Then, we dynamically create a new type derived from
# both it and our ``bundlerepository`` class which overrides some
# functionality. We then change the type of the constructed repository
# to this new type and initialize the bundle-specific bits of it.
try:
repo = localrepo.instance(ui, repopath, create=False)
tempparent = None
except error.RepoError:
tempparent = pycompat.mkdtemp()
try:
repo = localrepo.instance(ui, tempparent, create=True)
except Exception:
shutil.rmtree(tempparent)
raise
class derivedbundlerepository(bundlerepository, repo.__class__):
pass
repo.__class__ = derivedbundlerepository
bundlerepository.__init__(repo, bundlepath, url, tempparent)
return repo
class bundletransactionmanager(object):
def transaction(self):
return None
def close(self):
raise NotImplementedError
def release(self):
raise NotImplementedError
def getremotechanges(ui, repo, peer, onlyheads=None, bundlename=None,
force=False):
'''obtains a bundle of changes incoming from peer
"onlyheads" restricts the returned changes to those reachable from the
specified heads.
"bundlename", if given, stores the bundle to this file path permanently;
otherwise it's stored to a temp file and gets deleted again when you call
the returned "cleanupfn".
"force" indicates whether to proceed on unrelated repos.
Returns a tuple (local, csets, cleanupfn):
"local" is a local repo from which to obtain the actual incoming
changesets; it is a bundlerepo for the obtained bundle when the
original "peer" is remote.
"csets" lists the incoming changeset node ids.
"cleanupfn" must be called without arguments when you're done processing
the changes; it closes both the original "peer" and the one returned
here.
'''
tmp = discovery.findcommonincoming(repo, peer, heads=onlyheads,
force=force)
common, incoming, rheads = tmp
if not incoming:
try:
if bundlename:
os.unlink(bundlename)
except OSError:
pass
return repo, [], peer.close
commonset = set(common)
rheads = [x for x in rheads if x not in commonset]
bundle = None
bundlerepo = None
localrepo = peer.local()
if bundlename or not localrepo:
# create a bundle (uncompressed if peer repo is not local)
# developer config: devel.legacy.exchange
legexc = ui.configlist('devel', 'legacy.exchange')
forcebundle1 = 'bundle2' not in legexc and 'bundle1' in legexc
canbundle2 = (not forcebundle1
and peer.capable('getbundle')
and peer.capable('bundle2'))
if canbundle2:
with peer.commandexecutor() as e:
b2 = e.callcommand('getbundle', {
'source': 'incoming',
'common': common,
'heads': rheads,
'bundlecaps': exchange.caps20to10(repo, role='client'),
'cg': True,
}).result()
fname = bundle = changegroup.writechunks(ui,
b2._forwardchunks(),
bundlename)
else:
if peer.capable('getbundle'):
with peer.commandexecutor() as e:
cg = e.callcommand('getbundle', {
'source': 'incoming',
'common': common,
'heads': rheads,
}).result()
elif onlyheads is None and not peer.capable('changegroupsubset'):
# compat with older servers when pulling all remote heads
with peer.commandexecutor() as e:
cg = e.callcommand('changegroup', {
'nodes': incoming,
'source': 'incoming',
}).result()
rheads = None
else:
with peer.commandexecutor() as e:
cg = e.callcommand('changegroupsubset', {
'bases': incoming,
'heads': rheads,
'source': 'incoming',
}).result()
if localrepo:
bundletype = "HG10BZ"
else:
bundletype = "HG10UN"
fname = bundle = bundle2.writebundle(ui, cg, bundlename,
bundletype)
# keep written bundle?
if bundlename:
bundle = None
if not localrepo:
# use the created uncompressed bundlerepo
localrepo = bundlerepo = makebundlerepository(repo. baseui,
repo.root,
fname)
# this repo contains local and peer now, so filter out local again
common = repo.heads()
if localrepo:
# Part of common may be remotely filtered
# So use an unfiltered version
# The discovery process probably need cleanup to avoid that
localrepo = localrepo.unfiltered()
csets = localrepo.changelog.findmissing(common, rheads)
if bundlerepo:
reponodes = [ctx.node() for ctx in bundlerepo[bundlerepo.firstnewrev:]]
with peer.commandexecutor() as e:
remotephases = e.callcommand('listkeys', {
'namespace': 'phases',
}).result()
pullop = exchange.pulloperation(bundlerepo, peer, heads=reponodes)
pullop.trmanager = bundletransactionmanager()
exchange._pullapplyphases(pullop, remotephases)
def cleanup():
if bundlerepo:
bundlerepo.close()
if bundle:
os.unlink(bundle)
peer.close()
return (localrepo, csets, cleanup)