view mercurial/hg.py @ 2612:ffb895f16925

add support for streaming clone. existing clone code uses pull to get changes from remote repo. is very slow, uses lots of memory and cpu. new clone code has server write file data straight to client, client writes file data straight to disk. memory and cpu used are very low, clone is much faster over lan. new client can still clone with pull, can still clone from older servers. new server can still serve older clients.
author Vadim Gelfer <vadim.gelfer@gmail.com>
date Fri, 14 Jul 2006 11:17:22 -0700
parents c4325f0a9b91
children 479e26afa10f
line wrap: on
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# hg.py - repository classes for mercurial
#
# Copyright 2005 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.

from node import *
from repo import *
from demandload import *
from i18n import gettext as _
demandload(globals(), "localrepo bundlerepo httprepo sshrepo statichttprepo")
demandload(globals(), "errno lock os shutil util")

def bundle(ui, path):
    if path.startswith('bundle://'):
        path = path[9:]
    else:
        path = path[7:]
    s = path.split("+", 1)
    if len(s) == 1:
        repopath, bundlename = "", s[0]
    else:
        repopath, bundlename = s
    return bundlerepo.bundlerepository(ui, repopath, bundlename)

def hg(ui, path):
    ui.warn(_("hg:// syntax is deprecated, please use http:// instead\n"))
    return httprepo.httprepository(ui, path.replace("hg://", "http://"))

def local_(ui, path, create=0):
    if path.startswith('file:'):
        path = path[5:]
    return localrepo.localrepository(ui, path, create)

def ssh_(ui, path, create=0):
    return sshrepo.sshrepository(ui, path, create)

def old_http(ui, path):
    ui.warn(_("old-http:// syntax is deprecated, "
              "please use static-http:// instead\n"))
    return statichttprepo.statichttprepository(
        ui, path.replace("old-http://", "http://"))

def static_http(ui, path):
    return statichttprepo.statichttprepository(
        ui, path.replace("static-http://", "http://"))

schemes = {
    'bundle': bundle,
    'file': local_,
    'hg': hg,
    'http': lambda ui, path: httprepo.httprepository(ui, path),
    'https': lambda ui, path: httprepo.httpsrepository(ui, path),
    'old-http': old_http,
    'ssh': ssh_,
    'static-http': static_http,
    }

def repository(ui, path=None, create=0):
    scheme = None
    if path:
        c = path.find(':')
        if c > 0:
            scheme = schemes.get(path[:c])
    else:
        path = ''
    ctor = scheme or schemes['file']
    if create:
        try:
            return ctor(ui, path, create)
        except TypeError:
            raise util.Abort(_('cannot create new repository over "%s" protocol') %
                             scheme)
    return ctor(ui, path)

def clone(ui, source, dest=None, pull=False, rev=None, update=True):
    """Make a copy of an existing repository.

    Create a copy of an existing repository in a new directory.  The
    source and destination are URLs, as passed to the repository
    function.  Returns a pair of repository objects, the source and
    newly created destination.

    The location of the source is added to the new repository's
    .hg/hgrc file, as the default to be used for future pulls and
    pushes.

    If an exception is raised, the partly cloned/updated destination
    repository will be deleted.

    Keyword arguments:

    dest: URL of destination repository to create (defaults to base
    name of source repository)

    pull: always pull from source repository, even in local case

    rev: revision to clone up to (implies pull=True)

    update: update working directory after clone completes, if
    destination is local repository
    """
    if dest is None:
        dest = os.path.basename(os.path.normpath(source))

    if os.path.exists(dest):
        raise util.Abort(_("destination '%s' already exists"), dest)

    class DirCleanup(object):
        def __init__(self, dir_):
            self.rmtree = shutil.rmtree
            self.dir_ = dir_
        def close(self):
            self.dir_ = None
        def __del__(self):
            if self.dir_:
                self.rmtree(self.dir_, True)

    src_repo = repository(ui, source)

    dest_repo = None
    try:
        dest_repo = repository(ui, dest)
        raise util.Abort(_("destination '%s' already exists." % dest))
    except RepoError:
        dest_repo = repository(ui, dest, create=True)

    dest_path = None
    dir_cleanup = None
    if dest_repo.local():
        dest_path = os.path.realpath(dest)
        dir_cleanup = DirCleanup(dest_path)

    abspath = source
    copy = False
    if src_repo.local() and dest_repo.local():
        abspath = os.path.abspath(source)
        copy = not pull and not rev

    src_lock, dest_lock = None, None
    if copy:
        try:
            # we use a lock 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
            src_lock = src_repo.lock()
        except lock.LockException:
            copy = False

    if copy:
        # we lock here to avoid premature writing to the target
        dest_lock = lock.lock(os.path.join(dest_path, ".hg", "lock"))

	# we need to remove the (empty) data dir in dest so copyfiles
	# can do its work
	os.rmdir(os.path.join(dest_path, ".hg", "data"))
        files = "data 00manifest.d 00manifest.i 00changelog.d 00changelog.i"
        for f in files.split():
            src = os.path.join(source, ".hg", f)
            dst = os.path.join(dest_path, ".hg", f)
            try:
                util.copyfiles(src, dst)
            except OSError, inst:
                if inst.errno != errno.ENOENT:
                    raise

	# we need to re-init the repo after manually copying the data
	# into it
        dest_repo = repository(ui, dest)

    else:
        revs = None
        if rev:
            if not src_repo.local():
                raise util.Abort(_("clone by revision not supported yet "
                                   "for remote repositories"))
            revs = [src_repo.lookup(r) for r in rev]

        if dest_repo.local():
            dest_repo.clone(src_repo, heads=revs, pull=pull)
        elif src_repo.local():
            src_repo.push(dest_repo, revs=revs)
        else:
            raise util.Abort(_("clone from remote to remote not supported"))

    if src_lock:
        src_lock.release()

    if dest_repo.local():
        fp = dest_repo.opener("hgrc", "w", text=True)
        fp.write("[paths]\n")
        fp.write("default = %s\n" % abspath)
        fp.close()

        if dest_lock:
            dest_lock.release()

        if update:
            dest_repo.update(dest_repo.changelog.tip())
    if dir_cleanup:
        dir_cleanup.close()

    return src_repo, dest_repo