exchangev2: fetch manifest revisions
Now that the server has support for retrieving manifest data, we can
implement the client bits to call it.
We teach the changeset fetching code to capture the manifest revisions
that are encountered on incoming changesets. We then feed this into a
new function which filters out known manifests and then batches up
manifest data requests to the server.
This is different from the previous wire protocol in a few notable
ways.
First, the client fetches manifest data separately and explicitly.
Before, we'd ask the server for data pertaining to some changesets
(via a "getbundle" command) and manifests (and files) would be sent
automatically. Providing an API for looking up just manifest data
separately gives clients much more flexibility for manifest management.
For example, a client may choose to only fetch manifest data on demand
instead of prefetching it (i.e. partial clone).
Second, we send N commands to the server for manifest retrieval instead
of 1. This property has a few nice side-effects. One is that the
deterministic nature of the requests lends itself to server-side
caching. For example, say the remote has 50,000 manifests. If the
server is configured to cache responses, each time a new commit
arrives, you will have a cache miss and need to regenerate all outgoing
data. But if you makes N requests requesting 10,000 manifests each,
a new commit will still yield cache hits on the initial, unchanged
manifest batches/requests.
A derived benefit from these properties is that resumable clone is
conceptually simpler to implement. When making a monolithic request
for all of the repository data, recovering from an interrupted clone
is hard because the server was in the driver's seat and was maintaining
state about all the data that needed transferred. With the client
driving fetching, the client can persist the set of unfetched entities
and retry/resume a fetch if something goes wrong. Or we can fetch all
data N changesets at a time and slowly build up a repository. This
approach is drastically easier to implement when we have server APIs
exposing low-level repository primitives (such as manifests and files).
We don't yet support tree manifests. But it should be possible to
implement that with the existing wire protocol command.
Differential Revision: https://phab.mercurial-scm.org/D4489
# amend.py - provide the amend command
#
# Copyright 2017 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""provide the amend command (EXPERIMENTAL)
This extension provides an ``amend`` command that is similar to
``commit --amend`` but does not prompt an editor.
"""
from __future__ import absolute_import
from mercurial.i18n import _
from mercurial import (
cmdutil,
commands,
error,
pycompat,
registrar,
)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'
cmdtable = {}
command = registrar.command(cmdtable)
@command('amend',
[('A', 'addremove', None,
_('mark new/missing files as added/removed before committing')),
('e', 'edit', None, _('invoke editor on commit messages')),
('i', 'interactive', None, _('use interactive mode')),
('n', 'note', '', _('store a note on the amend')),
] + cmdutil.walkopts + cmdutil.commitopts + cmdutil.commitopts2,
_('[OPTION]... [FILE]...'),
inferrepo=True)
def amend(ui, repo, *pats, **opts):
"""amend the working copy parent with all or specified outstanding changes
Similar to :hg:`commit --amend`, but reuse the commit message without
invoking editor, unless ``--edit`` was set.
See :hg:`help commit` for more details.
"""
opts = pycompat.byteskwargs(opts)
if len(opts['note']) > 255:
raise error.Abort(_("cannot store a note of more than 255 bytes"))
with repo.wlock(), repo.lock():
if not opts.get('logfile'):
opts['message'] = opts.get('message') or repo['.'].description()
opts['amend'] = True
return commands._docommit(ui, repo, *pats, **pycompat.strkwargs(opts))