hg: make cachedlocalrepo cache appropriate repoview object
Before this patch, 'cachedlocalrepo' always caches "visible" repoview
object, because 'cachedlocalrepo' uses "visible" repoview returned by
'hg.repository()' without any additional processing.
If the client of 'cachedlocalrepo' wants "served" repoview, some
objects to be cached are discarded unintentionally.
1. 'cachedlocalrepo' newly caches "visible" repoview object
(call it VIEW1)
2. 'cachedlocalrepo' returns VIEW1 to the client of it at 'fetch()'
3. the client gets "served" repoview object by 'filtered("served")'
on VIEW1 (call this "served" repoview VIEW2)
4. accessing to 'repo.changelog' implies:
- instantiation of changelog via 'localrepository.changelog'
- instantiation of "filtered changelog" via 'repoview.changelog'
5. "filtered changelog" above is cached in VIEW2
6. VIEW2 is discarded after processing, because there is no
reference to it
7. 'cachedlocalrepo' returns VIEW1 cached at (1) above to the
client at next 'fetch()'
8. 'filtered("served")' on VIEW1 at the client side creates new
"served" repoview again, because VIEW1 is "visible"
(call this new "served" repoview VIEW3)
9. accessing to 'repo.changelog' implies instantiation of filtered
changelog again, because "filtered changelog" is cached in
VIEW2 at (5), but not in VIEW3 currently used
10. (go to (7) above)
As described above, "served" repoview object and "filtered changelog"
cached in it are discarded always, even if the repository itself
hasn't been changed since last access.
For example, in the case of 'hgweb_mod.hgweb', "newly caching" occurs,
when:
- all cached objects are already assigned to another threads
(in this case, repoview is created in 'cachedlocalrepo.copy()')
- or, stat of '00changelog.i' is changed from last access
(in this case, repoview is created in 'cachedlocalrepo.fetch()')
once changes are pushed via HTTP, this always occurs.
The root cause of this inefficiency is that 'cachedlocalrepo' always
caches "visible" repoview object, even if the client of it wants
another view.
To make 'cachedlocalrepo' cache appropriate repoview object, this
patch adds additional filtering on the repo object returned by
'hg.repository()'. It is assumed that initial repoview object should
be already filtered by expected view.
After this patch:
- 'filtered("served")' on VIEW1 at (3)/(7) above returns VIEW1
itself, because VIEW1 is now "served", and
- VIEW2 and VIEW3 equal VIEW1
- therefore, "filtered changelog" is cached in VIEW1, and reused
intentionally
# Copyright 2009, Alexander Solovyov <piranha@piranha.org.ua>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""extend schemes with shortcuts to repository swarms
This extension allows you to specify shortcuts for parent URLs with a
lot of repositories to act like a scheme, for example::
[schemes]
py = http://code.python.org/hg/
After that you can use it like::
hg clone py://trunk/
Additionally there is support for some more complex schemas, for
example used by Google Code::
[schemes]
gcode = http://{1}.googlecode.com/hg/
The syntax is taken from Mercurial templates, and you have unlimited
number of variables, starting with ``{1}`` and continuing with
``{2}``, ``{3}`` and so on. This variables will receive parts of URL
supplied, split by ``/``. Anything not specified as ``{part}`` will be
just appended to an URL.
For convenience, the extension adds these schemes by default::
[schemes]
py = http://hg.python.org/
bb = https://bitbucket.org/
bb+ssh = ssh://hg@bitbucket.org/
gcode = https://{1}.googlecode.com/hg/
kiln = https://{1}.kilnhg.com/Repo/
You can override a predefined scheme by defining a new scheme with the
same name.
"""
import os, re
from mercurial import extensions, hg, templater, util, error, cmdutil
from mercurial.i18n import _
cmdtable = {}
command = cmdutil.command(cmdtable)
# 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'
class ShortRepository(object):
def __init__(self, url, scheme, templater):
self.scheme = scheme
self.templater = templater
self.url = url
try:
self.parts = max(map(int, re.findall(r'\{(\d+)\}', self.url)))
except ValueError:
self.parts = 0
def __repr__(self):
return '<ShortRepository: %s>' % self.scheme
def instance(self, ui, url, create):
url = self.resolve(url)
return hg._peerlookup(url).instance(ui, url, create)
def resolve(self, url):
# Should this use the util.url class, or is manual parsing better?
try:
url = url.split('://', 1)[1]
except IndexError:
raise error.Abort(_("no '://' in scheme url '%s'") % url)
parts = url.split('/', self.parts)
if len(parts) > self.parts:
tail = parts[-1]
parts = parts[:-1]
else:
tail = ''
context = dict((str(i + 1), v) for i, v in enumerate(parts))
return ''.join(self.templater.process(self.url, context)) + tail
def hasdriveletter(orig, path):
if path:
for scheme in schemes:
if path.startswith(scheme + ':'):
return False
return orig(path)
schemes = {
'py': 'http://hg.python.org/',
'bb': 'https://bitbucket.org/',
'bb+ssh': 'ssh://hg@bitbucket.org/',
'gcode': 'https://{1}.googlecode.com/hg/',
'kiln': 'https://{1}.kilnhg.com/Repo/'
}
def extsetup(ui):
schemes.update(dict(ui.configitems('schemes')))
t = templater.engine(lambda x: x)
for scheme, url in schemes.items():
if (os.name == 'nt' and len(scheme) == 1 and scheme.isalpha()
and os.path.exists('%s:\\' % scheme)):
raise error.Abort(_('custom scheme %s:// conflicts with drive '
'letter %s:\\\n') % (scheme, scheme.upper()))
hg.schemes[scheme] = ShortRepository(url, scheme, t)
extensions.wrapfunction(util, 'hasdriveletter', hasdriveletter)
@command('debugexpandscheme', norepo=True)
def expandscheme(ui, url, **opts):
"""given a repo path, provide the scheme-expanded path
"""
repo = hg._peerlookup(url)
if isinstance(repo, ShortRepository):
url = repo.resolve(url)
ui.write(url + '\n')