revlog: change generaldelta delta parent heuristic
The old generaldelta heuristic was "if p1 (or p2) was closer than the last full text,
use it, otherwise use prev". This was problematic when a repo contained multiple
branches that were very different. If commits to branch A were pushed, and the
last full text was branch B, it would generate a fulltext. Then if branch B was
pushed, it would generate another fulltext. The problem is that the last
fulltext (and delta'ing against `prev` in general) has no correlation with the
contents of the incoming revision, and therefore will always have degenerate
cases.
According to the blame, that algorithm was chosen to minimize the chain length.
Since there is already code that protects against that (the delta-vs-fulltext
code), and since it has been improved since the original generaldelta algorithm
went in (2011), I believe the chain length criteria will still be preserved.
The new algorithm always diffs against p1 (or p2 if it's closer), unless the
resulting delta will fail the delta-vs-fulltext check, in which case we delta
against prev.
Some before and after stats on manifest.d size.
internal large repo
old heuristic - 2.0 GB
new heuristic - 1.2 GB
mozilla-central
old heuristic - 242 MB
new heuristic - 261 MB
The regression in mozilla central is due to the new heuristic choosing p2r as
the delta when it's closer to the tip. Switching the algorithm to always prefer
p1r brings the size back down (242 MB). This is result of the way in which
mozilla does merges and pushes, and the result could easily swing the other
direction in other repos (depending on if they merge X into Y or Y into X), but
will never be as degenerate as before.
I future patch will address the regression by introducing an optional, even more
aggressive delta heuristic which will knock the mozilla manifest size down
dramatically.
# notify.py - email notifications 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.
'''hooks for sending email push notifications
This extension implements hooks to send email notifications when
changesets are sent from or received by the local repository.
First, enable the extension as explained in :hg:`help extensions`, and
register the hook you want to run. ``incoming`` and ``changegroup`` hooks
are run when changesets are received, while ``outgoing`` hooks are for
changesets sent to another repository::
[hooks]
# one email for each incoming changeset
incoming.notify = python:hgext.notify.hook
# one email for all incoming changesets
changegroup.notify = python:hgext.notify.hook
# one email for all outgoing changesets
outgoing.notify = python:hgext.notify.hook
This registers the hooks. To enable notification, subscribers must
be assigned to repositories. The ``[usersubs]`` section maps multiple
repositories to a given recipient. The ``[reposubs]`` section maps
multiple recipients to a single repository::
[usersubs]
# key is subscriber email, value is a comma-separated list of repo patterns
user@host = pattern
[reposubs]
# key is repo pattern, value is a comma-separated list of subscriber emails
pattern = user@host
A ``pattern`` is a ``glob`` matching the absolute path to a repository,
optionally combined with a revset expression. A revset expression, if
present, is separated from the glob by a hash. Example::
[reposubs]
*/widgets#branch(release) = qa-team@example.com
This sends to ``qa-team@example.com`` whenever a changeset on the ``release``
branch triggers a notification in any repository ending in ``widgets``.
In order to place them under direct user management, ``[usersubs]`` and
``[reposubs]`` sections may be placed in a separate ``hgrc`` file and
incorporated by reference::
[notify]
config = /path/to/subscriptionsfile
Notifications will not be sent until the ``notify.test`` value is set
to ``False``; see below.
Notifications content can be tweaked with the following configuration entries:
notify.test
If ``True``, print messages to stdout instead of sending them. Default: True.
notify.sources
Space-separated list of change sources. Notifications are activated only
when a changeset's source is in this list. Sources may be:
:``serve``: changesets received via http or ssh
:``pull``: changesets received via ``hg pull``
:``unbundle``: changesets received via ``hg unbundle``
:``push``: changesets sent or received via ``hg push``
:``bundle``: changesets sent via ``hg unbundle``
Default: serve.
notify.strip
Number of leading slashes to strip from url paths. By default, notifications
reference repositories with their absolute path. ``notify.strip`` lets you
turn them into relative paths. For example, ``notify.strip=3`` will change
``/long/path/repository`` into ``repository``. Default: 0.
notify.domain
Default email domain for sender or recipients with no explicit domain.
notify.style
Style file to use when formatting emails.
notify.template
Template to use when formatting emails.
notify.incoming
Template to use when run as an incoming hook, overriding ``notify.template``.
notify.outgoing
Template to use when run as an outgoing hook, overriding ``notify.template``.
notify.changegroup
Template to use when running as a changegroup hook, overriding
``notify.template``.
notify.maxdiff
Maximum number of diff lines to include in notification email. Set to 0
to disable the diff, or -1 to include all of it. Default: 300.
notify.maxsubject
Maximum number of characters in email's subject line. Default: 67.
notify.diffstat
Set to True to include a diffstat before diff content. Default: True.
notify.merge
If True, send notifications for merge changesets. Default: True.
notify.mbox
If set, append mails to this mbox file instead of sending. Default: None.
notify.fromauthor
If set, use the committer of the first changeset in a changegroup for
the "From" field of the notification mail. If not set, take the user
from the pushing repo. Default: False.
If set, the following entries will also be used to customize the
notifications:
email.from
Email ``From`` address to use if none can be found in the generated
email content.
web.baseurl
Root repository URL to combine with repository paths when making
references. See also ``notify.strip``.
'''
import email, socket, time
from mercurial.i18n import _
from mercurial import patch, cmdutil, util, mail
import fnmatch
# Note for extension authors: ONLY specify testedwith = 'internal' 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 = 'internal'
# template for single changeset can include email headers.
single_template = '''
Subject: changeset in {webroot}: {desc|firstline|strip}
From: {author}
changeset {node|short} in {root}
details: {baseurl}{webroot}?cmd=changeset;node={node|short}
description:
\t{desc|tabindent|strip}
'''.lstrip()
# template for multiple changesets should not contain email headers,
# because only first set of headers will be used and result will look
# strange.
multiple_template = '''
changeset {node|short} in {root}
details: {baseurl}{webroot}?cmd=changeset;node={node|short}
summary: {desc|firstline}
'''
deftemplates = {
'changegroup': multiple_template,
}
class notifier(object):
'''email notification class.'''
def __init__(self, ui, repo, hooktype):
self.ui = ui
cfg = self.ui.config('notify', 'config')
if cfg:
self.ui.readconfig(cfg, sections=['usersubs', 'reposubs'])
self.repo = repo
self.stripcount = int(self.ui.config('notify', 'strip', 0))
self.root = self.strip(self.repo.root)
self.domain = self.ui.config('notify', 'domain')
self.mbox = self.ui.config('notify', 'mbox')
self.test = self.ui.configbool('notify', 'test', True)
self.charsets = mail._charsets(self.ui)
self.subs = self.subscribers()
self.merge = self.ui.configbool('notify', 'merge', True)
mapfile = self.ui.config('notify', 'style')
template = (self.ui.config('notify', hooktype) or
self.ui.config('notify', 'template'))
if not mapfile and not template:
template = deftemplates.get(hooktype) or single_template
self.t = cmdutil.changeset_templater(self.ui, self.repo, False, None,
template, mapfile, False)
def strip(self, path):
'''strip leading slashes from local path, turn into web-safe path.'''
path = util.pconvert(path)
count = self.stripcount
while count > 0:
c = path.find('/')
if c == -1:
break
path = path[c + 1:]
count -= 1
return path
def fixmail(self, addr):
'''try to clean up email addresses.'''
addr = util.email(addr.strip())
if self.domain:
a = addr.find('@localhost')
if a != -1:
addr = addr[:a]
if '@' not in addr:
return addr + '@' + self.domain
return addr
def subscribers(self):
'''return list of email addresses of subscribers to this repo.'''
subs = set()
for user, pats in self.ui.configitems('usersubs'):
for pat in pats.split(','):
if '#' in pat:
pat, revs = pat.split('#', 1)
else:
revs = None
if fnmatch.fnmatch(self.repo.root, pat.strip()):
subs.add((self.fixmail(user), revs))
for pat, users in self.ui.configitems('reposubs'):
if '#' in pat:
pat, revs = pat.split('#', 1)
else:
revs = None
if fnmatch.fnmatch(self.repo.root, pat):
for user in users.split(','):
subs.add((self.fixmail(user), revs))
return [(mail.addressencode(self.ui, s, self.charsets, self.test), r)
for s, r in sorted(subs)]
def node(self, ctx, **props):
'''format one changeset, unless it is a suppressed merge.'''
if not self.merge and len(ctx.parents()) > 1:
return False
self.t.show(ctx, changes=ctx.changeset(),
baseurl=self.ui.config('web', 'baseurl'),
root=self.repo.root, webroot=self.root, **props)
return True
def skipsource(self, source):
'''true if incoming changes from this source should be skipped.'''
ok_sources = self.ui.config('notify', 'sources', 'serve').split()
return source not in ok_sources
def send(self, ctx, count, data):
'''send message.'''
# Select subscribers by revset
subs = set()
for sub, spec in self.subs:
if spec is None:
subs.add(sub)
continue
revs = self.repo.revs('%r and %d:', spec, ctx.rev())
if len(revs):
subs.add(sub)
continue
if len(subs) == 0:
self.ui.debug('notify: no subscribers to selected repo '
'and revset\n')
return
p = email.Parser.Parser()
try:
msg = p.parsestr(data)
except email.Errors.MessageParseError as inst:
raise util.Abort(inst)
# store sender and subject
sender, subject = msg['From'], msg['Subject']
del msg['From'], msg['Subject']
if not msg.is_multipart():
# create fresh mime message from scratch
# (multipart templates must take care of this themselves)
headers = msg.items()
payload = msg.get_payload()
# for notification prefer readability over data precision
msg = mail.mimeencode(self.ui, payload, self.charsets, self.test)
# reinstate custom headers
for k, v in headers:
msg[k] = v
msg['Date'] = util.datestr(format="%a, %d %b %Y %H:%M:%S %1%2")
# try to make subject line exist and be useful
if not subject:
if count > 1:
subject = _('%s: %d new changesets') % (self.root, count)
else:
s = ctx.description().lstrip().split('\n', 1)[0].rstrip()
subject = '%s: %s' % (self.root, s)
maxsubject = int(self.ui.config('notify', 'maxsubject', 67))
if maxsubject:
subject = util.ellipsis(subject, maxsubject)
msg['Subject'] = mail.headencode(self.ui, subject,
self.charsets, self.test)
# try to make message have proper sender
if not sender:
sender = self.ui.config('email', 'from') or self.ui.username()
if '@' not in sender or '@localhost' in sender:
sender = self.fixmail(sender)
msg['From'] = mail.addressencode(self.ui, sender,
self.charsets, self.test)
msg['X-Hg-Notification'] = 'changeset %s' % ctx
if not msg['Message-Id']:
msg['Message-Id'] = ('<hg.%s.%s.%s@%s>' %
(ctx, int(time.time()),
hash(self.repo.root), socket.getfqdn()))
msg['To'] = ', '.join(sorted(subs))
msgtext = msg.as_string()
if self.test:
self.ui.write(msgtext)
if not msgtext.endswith('\n'):
self.ui.write('\n')
else:
self.ui.status(_('notify: sending %d subscribers %d changes\n') %
(len(subs), count))
mail.sendmail(self.ui, util.email(msg['From']),
subs, msgtext, mbox=self.mbox)
def diff(self, ctx, ref=None):
maxdiff = int(self.ui.config('notify', 'maxdiff', 300))
prev = ctx.p1().node()
if ref:
ref = ref.node()
else:
ref = ctx.node()
chunks = patch.diff(self.repo, prev, ref,
opts=patch.diffallopts(self.ui))
difflines = ''.join(chunks).splitlines()
if self.ui.configbool('notify', 'diffstat', True):
s = patch.diffstat(difflines)
# s may be nil, don't include the header if it is
if s:
self.ui.write('\ndiffstat:\n\n%s' % s)
if maxdiff == 0:
return
elif maxdiff > 0 and len(difflines) > maxdiff:
msg = _('\ndiffs (truncated from %d to %d lines):\n\n')
self.ui.write(msg % (len(difflines), maxdiff))
difflines = difflines[:maxdiff]
elif difflines:
self.ui.write(_('\ndiffs (%d lines):\n\n') % len(difflines))
self.ui.write("\n".join(difflines))
def hook(ui, repo, hooktype, node=None, source=None, **kwargs):
'''send email notifications to interested subscribers.
if used as changegroup hook, send one email for all changesets in
changegroup. else send one email per changeset.'''
n = notifier(ui, repo, hooktype)
ctx = repo[node]
if not n.subs:
ui.debug('notify: no subscribers to repository %s\n' % n.root)
return
if n.skipsource(source):
ui.debug('notify: changes have source "%s" - skipping\n' % source)
return
ui.pushbuffer()
data = ''
count = 0
author = ''
if hooktype == 'changegroup' or hooktype == 'outgoing':
start, end = ctx.rev(), len(repo)
for rev in xrange(start, end):
if n.node(repo[rev]):
count += 1
if not author:
author = repo[rev].user()
else:
data += ui.popbuffer()
ui.note(_('notify: suppressing notification for merge %d:%s\n')
% (rev, repo[rev].hex()[:12]))
ui.pushbuffer()
if count:
n.diff(ctx, repo['tip'])
else:
if not n.node(ctx):
ui.popbuffer()
ui.note(_('notify: suppressing notification for merge %d:%s\n') %
(ctx.rev(), ctx.hex()[:12]))
return
count += 1
n.diff(ctx)
data += ui.popbuffer()
fromauthor = ui.config('notify', 'fromauthor')
if author and fromauthor:
data = '\n'.join(['From: %s' % author, data])
if count:
n.send(ctx, count, data)