##// END OF EJS Templates
wireprotov2peer: stream decoded responses...
wireprotov2peer: stream decoded responses Previously, wire protocol version 2 would buffer all response data. Only once all data was received did we CBOR decode it and resolve the future associated with the command. This was obviously not desirable. In future commits that introduce large response payloads, this caused significant memory bloat and slowed down client operations due to waiting on the server. This commit refactors the response handling code so that response data can be streamed. Command response objects now contain a buffered CBOR decoder. As new data arrives, it is fed into the decoder. Decoded objects are made available to the generator as they are decoded. Because there is a separate thread processing incoming frames and feeding data into the response object, there is the potential for race conditions when mutating response objects. So a lock has been added to guard access to critical state variables. Because the generator emitting decoded objects needs to wait on those objects to become available, we've added an Event for the generator to wait on so it doesn't busy loop. This does mean there is the potential for deadlocks. And I'm pretty sure they can occur in some scenarios. We already have a handful of TODOs around this. But I've added some more. Fixing this will likely require moving the background thread receiving frames into clienthandler. We likely would have done this anyway when implementing the client bits for the SSH transport. Test output changes because the initial CBOR map holding the overall response state is now always handled internally by the response object. Differential Revision: https://phab.mercurial-scm.org/D4474

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archival.py
344 lines | 10.8 KiB | text/x-python | PythonLexer
# archival.py - revision archival for mercurial
#
# Copyright 2006 Vadim Gelfer <vadim.gelfer@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.
from __future__ import absolute_import
import gzip
import os
import struct
import tarfile
import time
import zipfile
import zlib
from .i18n import _
from . import (
error,
formatter,
match as matchmod,
pycompat,
scmutil,
util,
vfs as vfsmod,
)
stringio = util.stringio
# from unzip source code:
_UNX_IFREG = 0x8000
_UNX_IFLNK = 0xa000
def tidyprefix(dest, kind, prefix):
'''choose prefix to use for names in archive. make sure prefix is
safe for consumers.'''
if prefix:
prefix = util.normpath(prefix)
else:
if not isinstance(dest, bytes):
raise ValueError('dest must be string if no prefix')
prefix = os.path.basename(dest)
lower = prefix.lower()
for sfx in exts.get(kind, []):
if lower.endswith(sfx):
prefix = prefix[:-len(sfx)]
break
lpfx = os.path.normpath(util.localpath(prefix))
prefix = util.pconvert(lpfx)
if not prefix.endswith('/'):
prefix += '/'
# Drop the leading '.' path component if present, so Windows can read the
# zip files (issue4634)
if prefix.startswith('./'):
prefix = prefix[2:]
if prefix.startswith('../') or os.path.isabs(lpfx) or '/../' in prefix:
raise error.Abort(_('archive prefix contains illegal components'))
return prefix
exts = {
'tar': ['.tar'],
'tbz2': ['.tbz2', '.tar.bz2'],
'tgz': ['.tgz', '.tar.gz'],
'zip': ['.zip'],
}
def guesskind(dest):
for kind, extensions in exts.iteritems():
if any(dest.endswith(ext) for ext in extensions):
return kind
return None
def _rootctx(repo):
# repo[0] may be hidden
for rev in repo:
return repo[rev]
return repo['null']
# {tags} on ctx includes local tags and 'tip', with no current way to limit
# that to global tags. Therefore, use {latesttag} as a substitute when
# the distance is 0, since that will be the list of global tags on ctx.
_defaultmetatemplate = br'''
repo: {root}
node: {ifcontains(rev, revset("wdir()"), "{p1node}{dirty}", "{node}")}
branch: {branch|utf8}
{ifeq(latesttagdistance, 0, join(latesttag % "tag: {tag}", "\n"),
separate("\n",
join(latesttag % "latesttag: {tag}", "\n"),
"latesttagdistance: {latesttagdistance}",
"changessincelatesttag: {changessincelatesttag}"))}
'''[1:] # drop leading '\n'
def buildmetadata(ctx):
'''build content of .hg_archival.txt'''
repo = ctx.repo()
opts = {
'template': repo.ui.config('experimental', 'archivemetatemplate',
_defaultmetatemplate)
}
out = util.stringio()
fm = formatter.formatter(repo.ui, out, 'archive', opts)
fm.startitem()
fm.context(ctx=ctx)
fm.data(root=_rootctx(repo).hex())
if ctx.rev() is None:
dirty = ''
if ctx.dirty(missing=True):
dirty = '+'
fm.data(dirty=dirty)
fm.end()
return out.getvalue()
class tarit(object):
'''write archive to tar file or stream. can write uncompressed,
or compress with gzip or bzip2.'''
class GzipFileWithTime(gzip.GzipFile):
def __init__(self, *args, **kw):
timestamp = None
if r'timestamp' in kw:
timestamp = kw.pop(r'timestamp')
if timestamp is None:
self.timestamp = time.time()
else:
self.timestamp = timestamp
gzip.GzipFile.__init__(self, *args, **kw)
def _write_gzip_header(self):
self.fileobj.write('\037\213') # magic header
self.fileobj.write('\010') # compression method
fname = self.name
if fname and fname.endswith('.gz'):
fname = fname[:-3]
flags = 0
if fname:
flags = gzip.FNAME
self.fileobj.write(pycompat.bytechr(flags))
gzip.write32u(self.fileobj, int(self.timestamp))
self.fileobj.write('\002')
self.fileobj.write('\377')
if fname:
self.fileobj.write(fname + '\000')
def __init__(self, dest, mtime, kind=''):
self.mtime = mtime
self.fileobj = None
def taropen(mode, name='', fileobj=None):
if kind == 'gz':
mode = mode[0:1]
if not fileobj:
fileobj = open(name, mode + 'b')
gzfileobj = self.GzipFileWithTime(name,
pycompat.sysstr(mode + 'b'),
zlib.Z_BEST_COMPRESSION,
fileobj, timestamp=mtime)
self.fileobj = gzfileobj
return tarfile.TarFile.taropen(
name, pycompat.sysstr(mode), gzfileobj)
else:
return tarfile.open(
name, pycompat.sysstr(mode + kind), fileobj)
if isinstance(dest, bytes):
self.z = taropen('w:', name=dest)
else:
self.z = taropen('w|', fileobj=dest)
def addfile(self, name, mode, islink, data):
name = pycompat.fsdecode(name)
i = tarfile.TarInfo(name)
i.mtime = self.mtime
i.size = len(data)
if islink:
i.type = tarfile.SYMTYPE
i.mode = 0o777
i.linkname = pycompat.fsdecode(data)
data = None
i.size = 0
else:
i.mode = mode
data = stringio(data)
self.z.addfile(i, data)
def done(self):
self.z.close()
if self.fileobj:
self.fileobj.close()
class zipit(object):
'''write archive to zip file or stream. can write uncompressed,
or compressed with deflate.'''
def __init__(self, dest, mtime, compress=True):
self.z = zipfile.ZipFile(pycompat.fsdecode(dest), r'w',
compress and zipfile.ZIP_DEFLATED or
zipfile.ZIP_STORED)
# Python's zipfile module emits deprecation warnings if we try
# to store files with a date before 1980.
epoch = 315532800 # calendar.timegm((1980, 1, 1, 0, 0, 0, 1, 1, 0))
if mtime < epoch:
mtime = epoch
self.mtime = mtime
self.date_time = time.gmtime(mtime)[:6]
def addfile(self, name, mode, islink, data):
i = zipfile.ZipInfo(pycompat.fsdecode(name), self.date_time)
i.compress_type = self.z.compression
# unzip will not honor unix file modes unless file creator is
# set to unix (id 3).
i.create_system = 3
ftype = _UNX_IFREG
if islink:
mode = 0o777
ftype = _UNX_IFLNK
i.external_attr = (mode | ftype) << 16
# add "extended-timestamp" extra block, because zip archives
# without this will be extracted with unexpected timestamp,
# if TZ is not configured as GMT
i.extra += struct.pack('<hhBl',
0x5455, # block type: "extended-timestamp"
1 + 4, # size of this block
1, # "modification time is present"
int(self.mtime)) # last modification (UTC)
self.z.writestr(i, data)
def done(self):
self.z.close()
class fileit(object):
'''write archive as files in directory.'''
def __init__(self, name, mtime):
self.basedir = name
self.opener = vfsmod.vfs(self.basedir)
self.mtime = mtime
def addfile(self, name, mode, islink, data):
if islink:
self.opener.symlink(data, name)
return
f = self.opener(name, "w", atomictemp=False)
f.write(data)
f.close()
destfile = os.path.join(self.basedir, name)
os.chmod(destfile, mode)
if self.mtime is not None:
os.utime(destfile, (self.mtime, self.mtime))
def done(self):
pass
archivers = {
'files': fileit,
'tar': tarit,
'tbz2': lambda name, mtime: tarit(name, mtime, 'bz2'),
'tgz': lambda name, mtime: tarit(name, mtime, 'gz'),
'uzip': lambda name, mtime: zipit(name, mtime, False),
'zip': zipit,
}
def archive(repo, dest, node, kind, decode=True, matchfn=None,
prefix='', mtime=None, subrepos=False):
'''create archive of repo as it was at node.
dest can be name of directory, name of archive file, or file
object to write archive to.
kind is type of archive to create.
decode tells whether to put files through decode filters from
hgrc.
matchfn is function to filter names of files to write to archive.
prefix is name of path to put before every archive member.
mtime is the modified time, in seconds, or None to use the changeset time.
subrepos tells whether to include subrepos.
'''
if kind == 'files':
if prefix:
raise error.Abort(_('cannot give prefix when archiving to files'))
else:
prefix = tidyprefix(dest, kind, prefix)
def write(name, mode, islink, getdata):
data = getdata()
if decode:
data = repo.wwritedata(name, data)
archiver.addfile(prefix + name, mode, islink, data)
if kind not in archivers:
raise error.Abort(_("unknown archive type '%s'") % kind)
ctx = repo[node]
archiver = archivers[kind](dest, mtime or ctx.date()[0])
if repo.ui.configbool("ui", "archivemeta"):
name = '.hg_archival.txt'
if not matchfn or matchfn(name):
write(name, 0o644, False, lambda: buildmetadata(ctx))
if matchfn:
files = [f for f in ctx.manifest().keys() if matchfn(f)]
else:
files = ctx.manifest().keys()
total = len(files)
if total:
files.sort()
scmutil.prefetchfiles(repo, [ctx.rev()],
scmutil.matchfiles(repo, files))
progress = scmutil.progress(repo.ui, _('archiving'), unit=_('files'),
total=total)
progress.update(0)
for f in files:
ff = ctx.flags(f)
write(f, 'x' in ff and 0o755 or 0o644, 'l' in ff, ctx[f].data)
progress.increment(item=f)
progress.complete()
if subrepos:
for subpath in sorted(ctx.substate):
sub = ctx.workingsub(subpath)
submatch = matchmod.subdirmatcher(subpath, matchfn)
total += sub.archive(archiver, prefix, submatch, decode)
if total == 0:
raise error.Abort(_('no files match the archive pattern'))
archiver.done()
return total