debugcommands: add debugwireproto command
We currently don't have a low-level mechanism for sending
arbitrary wire protocol commands. Having a generic and robust
mechanism for sending wire protocol commands, examining wire
data, etc would make it vastly easier to test the wire protocol
and debug server operation. This is a problem I've wanted a
solution for numerous times, especially recently as I've been
hacking on a new version of the wire protocol.
This commit establishes a `hg debugwireproto` command for sending
data to a peer.
The command invents a mini language for specifying actions to take.
This will enable a lot of flexibility for issuing commands and testing
variations for how commands are sent.
Right now, we only support low-level raw sends and receives. These
are probably the least valuable commands to intended users of this
command. But they are the most useful commands to implement to
bootstrap the feature (I've chosen to reimplement test-ssh-proto.t
using this command to prove its usefulness).
My eventual goal of `hg debugwireproto` is to allow calling wire
protocol commands with a human-friendly interface. Essentially,
people can type in a command name and arguments and
`hg debugwireproto` will figure out how to send that on the wire.
I'd love to eventually be able to save the server's raw response
to a file. This would allow us to e.g. call "getbundle" wire
protocol commands easily.
test-ssh-proto.t has been updated to use the new command in lieu
of piping directly to a server process. As part of the transition,
test behavior improved. Before, we piped all request data to the
server at once. Now, we have explicit control over the ordering of
operations. e.g. we can send one command, receive its response,
then send another command. This will allow us to more robustly
test race conditions, buffering behavior, etc.
There were some subtle changes in test behavior. For example,
previous behavior would often send trailing newlines to the server.
The new mechanism doesn't treat literal newlines specially and
requires newlines be escaped in the payload.
Because the new logging code is very low level, it is easy to
introduce race conditions in tests. For example, the number of bytes
returned by a read() may vary depending on load. This is why tests
make heavy use of "readline" for consuming data: the result of
that operation should be deterministic and not subject to race
conditions. There are still some uses of "readavailable." However,
those are only for reading from stderr. I was able to reproduce
timing issues with my system under load when using "readavailable"
globally. But if I "readline" to grab stdout, "readavailable"
appears to work deterministically for stderr. I think this is
because the server writes to stderr first. As long as the OS
delivers writes to pipes in the same order they were made, this
should work. If there are timing issues, we can introduce a
mechanism to readline from stderr.
Differential Revision: https://phab.mercurial-scm.org/D2392
# 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
import tempfile
from .i18n import _
from .node import nullid
from . import (
bundle2,
changegroup,
changelog,
cmdutil,
discovery,
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.insert(-1, 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._cache and self._cache[1] == iterrev:
rawtext = self._cache[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._cache = (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, dir=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(bundlerevlog, filelog.filelog):
def __init__(self, opener, path, cgunpacker, linkmapper):
filelog.filelog.__init__(self, opener, path)
bundlerevlog.__init__(self, 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(localrepo.localrepository):
"""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.
"""
def __init__(self, ui, repopath, bundlepath):
self._tempparent = None
try:
localrepo.localrepository.__init__(self, ui, repopath)
except error.RepoError:
self._tempparent = tempfile.mkdtemp()
localrepo.instance(ui, self._tempparent, 1)
localrepo.localrepository.__init__(self, ui, self._tempparent)
self.ui.setconfig('phases', 'publish', False, 'bundlerepo')
if repopath:
self._url = 'bundle:' + util.expandpath(repopath) + '+' + bundlepath
else:
self._url = 'bundle:' + bundlepath
self.tempfile = None
f = util.posixfile(bundlepath, "rb")
bundle = exchange.readbundle(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(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, pycompat.sysstr('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
def _constructmanifest(self):
self._cgunpacker.seek(self.manstart)
# consume the header if it exists
self._cgunpacker.manifestheader()
linkmapper = self.unfiltered().changelog.rev
m = bundlemanifest(self.svfs, self._cgunpacker, linkmapper)
self.filestart = self._cgunpacker.tell()
return m
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 filelog.filelog(self.svfs, 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 pycompat.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):
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(pycompat.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 = pycompat.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 bundlerepository(ui, repopath, bundlename)
class bundletransactionmanager(object):
def transaction(self):
return None
def close(self):
raise NotImplementedError
def release(self):
raise NotImplementedError
def getremotechanges(ui, repo, other, onlyheads=None, bundlename=None,
force=False):
'''obtains a bundle of changes incoming from other
"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 "other" 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 "other" and the one returned
here.
'''
tmp = discovery.findcommonincoming(repo, other, heads=onlyheads,
force=force)
common, incoming, rheads = tmp
if not incoming:
try:
if bundlename:
os.unlink(bundlename)
except OSError:
pass
return repo, [], other.close
commonset = set(common)
rheads = [x for x in rheads if x not in commonset]
bundle = None
bundlerepo = None
localrepo = other.local()
if bundlename or not localrepo:
# create a bundle (uncompressed if other 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 other.capable('getbundle')
and other.capable('bundle2'))
if canbundle2:
kwargs = {}
kwargs[r'common'] = common
kwargs[r'heads'] = rheads
kwargs[r'bundlecaps'] = exchange.caps20to10(repo, role='client')
kwargs[r'cg'] = True
b2 = other.getbundle('incoming', **kwargs)
fname = bundle = changegroup.writechunks(ui, b2._forwardchunks(),
bundlename)
else:
if other.capable('getbundle'):
cg = other.getbundle('incoming', common=common, heads=rheads)
elif onlyheads is None and not other.capable('changegroupsubset'):
# compat with older servers when pulling all remote heads
cg = other.changegroup(incoming, "incoming")
rheads = None
else:
cg = other.changegroupsubset(incoming, rheads, 'incoming')
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 = bundlerepository(repo.baseui, repo.root,
fname)
# this repo contains local and other 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:]]
remotephases = other.listkeys('phases')
pullop = exchange.pulloperation(bundlerepo, other, heads=reponodes)
pullop.trmanager = bundletransactionmanager()
exchange._pullapplyphases(pullop, remotephases)
def cleanup():
if bundlerepo:
bundlerepo.close()
if bundle:
os.unlink(bundle)
other.close()
return (localrepo, csets, cleanup)