view mercurial/streamclone.py @ 8496:a21605de1509

commit: move editor outside transaction

The commit editor is now invoked before files and manifest are
committed. The editor is now run with only the wlock held and aborting
an edit no longer requires rolling back a transaction. Changes to
files during a commit still result in undefined behavior.

(This is preliminary work for committing subrepositories)

# streamclone.py - streaming clone server support for mercurial
#
# Copyright 2006 Vadim Gelfer <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2, incorporated herein by reference.

import util, error
from i18n import _

class StreamException(Exception):
    def __init__(self, code):
        Exception.__init__(self)
        self.code = code
    def __str__(self):
        return '%i\n' % self.code

# if server supports streaming clone, it advertises "stream"
# capability with value that is version+flags of repo it is serving.
# client only streams if it can read that repo format.

# stream file format is simple.
#
# server writes out line that says how many files, how many total
# bytes.  separator is ascii space, byte counts are strings.
#
# then for each file:
#
#   server writes out line that says file name, how many bytes in
#   file.  separator is ascii nul, byte count is string.
#
#   server writes out raw file data.

def stream_out(repo, untrusted=False):
    '''stream out all metadata files in repository.
    writes to file-like object, must support write() and optional flush().'''

    if not repo.ui.configbool('server', 'uncompressed', untrusted=untrusted):
        raise StreamException(1)

    entries = []
    total_bytes = 0
    try:
        # get consistent snapshot of repo, lock during scan
        lock = repo.lock()
        try:
            repo.ui.debug(_('scanning\n'))
            for name, ename, size in repo.store.walk():
                entries.append((name, size))
                total_bytes += size
        finally:
            lock.release()
    except error.LockError:
        raise StreamException(2)

    yield '0\n'
    repo.ui.debug(_('%d files, %d bytes to transfer\n') %
                  (len(entries), total_bytes))
    yield '%d %d\n' % (len(entries), total_bytes)
    for name, size in entries:
        repo.ui.debug(_('sending %s (%d bytes)\n') % (name, size))
        yield '%s\0%d\n' % (name, size)
        for chunk in util.filechunkiter(repo.sopener(name), limit=size):
            yield chunk