hgweb: garbage collect on every request
There appears to be a cycle in localrepository or hgweb that
is preventing repositories from being garbage collected when
hgwebdir dispatches to hgweb. Every request creates a new
repository instance and then leaks that object and other referenced
objects. A periodic GC to find cycles will eventually collect the
old repositories. But these don't run reliably and rapid requests
to hgwebdir can result in rapidly increasing memory consumption.
With the Firefox repository, repeated requests to raw-file URLs
leak ~100 MB per hgwebdir request (most of this appears to be
cached manifest data structures). WSGI processes quickly grow
to >1 GB RSS.
Breaking the cycles in localrepository is going to be a bit of
work.
Because we know that hgwebdir leaks localrepository instances, let's
put a band aid on the problem in the form of an explicit gc.collect()
on every hgwebdir request.
As the inline comment states, ideally we'd do this in a finally
block for the current request iff it dispatches to hgweb. But
_runwsgi() returns an explicit value. We need the finally to run
after generator exhaustion. So we'd need to refactor _runwsgi()
to "yield" instead of "return." That's too much change for a patch
to stable. So we implement this hack one function above and run
it on every request.
The performance impact of this change should be minimal. Any
impact should be offset by benefits from not having hgwebdir
processes leak memory.
# hgweb/hgwebdir_mod.py - Web interface for a directory of repositories.
#
# Copyright 21 May 2005 - (c) 2005 Jake Edge <jake@edge2.net>
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import gc
import os
import re
import time
from ..i18n import _
from .common import (
ErrorResponse,
HTTP_NOT_FOUND,
HTTP_OK,
HTTP_SERVER_ERROR,
cspvalues,
get_contact,
get_mtime,
ismember,
paritygen,
staticfile,
)
from .request import wsgirequest
from .. import (
configitems,
encoding,
error,
hg,
profiling,
pycompat,
scmutil,
templater,
ui as uimod,
util,
)
from . import (
hgweb_mod,
webutil,
wsgicgi,
)
def cleannames(items):
return [(util.pconvert(name).strip('/'), path) for name, path in items]
def findrepos(paths):
repos = []
for prefix, root in cleannames(paths):
roothead, roottail = os.path.split(root)
# "foo = /bar/*" or "foo = /bar/**" lets every repo /bar/N in or below
# /bar/ be served as as foo/N .
# '*' will not search inside dirs with .hg (except .hg/patches),
# '**' will search inside dirs with .hg (and thus also find subrepos).
try:
recurse = {'*': False, '**': True}[roottail]
except KeyError:
repos.append((prefix, root))
continue
roothead = os.path.normpath(os.path.abspath(roothead))
paths = scmutil.walkrepos(roothead, followsym=True, recurse=recurse)
repos.extend(urlrepos(prefix, roothead, paths))
return repos
def urlrepos(prefix, roothead, paths):
"""yield url paths and filesystem paths from a list of repo paths
>>> conv = lambda seq: [(v, util.pconvert(p)) for v,p in seq]
>>> conv(urlrepos(b'hg', b'/opt', [b'/opt/r', b'/opt/r/r', b'/opt']))
[('hg/r', '/opt/r'), ('hg/r/r', '/opt/r/r'), ('hg', '/opt')]
>>> conv(urlrepos(b'', b'/opt', [b'/opt/r', b'/opt/r/r', b'/opt']))
[('r', '/opt/r'), ('r/r', '/opt/r/r'), ('', '/opt')]
"""
for path in paths:
path = os.path.normpath(path)
yield (prefix + '/' +
util.pconvert(path[len(roothead):]).lstrip('/')).strip('/'), path
def geturlcgivars(baseurl, port):
"""
Extract CGI variables from baseurl
>>> geturlcgivars(b"http://host.org/base", b"80")
('host.org', '80', '/base')
>>> geturlcgivars(b"http://host.org:8000/base", b"80")
('host.org', '8000', '/base')
>>> geturlcgivars(b'/base', 8000)
('', '8000', '/base')
>>> geturlcgivars(b"base", b'8000')
('', '8000', '/base')
>>> geturlcgivars(b"http://host", b'8000')
('host', '8000', '/')
>>> geturlcgivars(b"http://host/", b'8000')
('host', '8000', '/')
"""
u = util.url(baseurl)
name = u.host or ''
if u.port:
port = u.port
path = u.path or ""
if not path.startswith('/'):
path = '/' + path
return name, pycompat.bytestr(port), path
class hgwebdir(object):
"""HTTP server for multiple repositories.
Given a configuration, different repositories will be served depending
on the request path.
Instances are typically used as WSGI applications.
"""
def __init__(self, conf, baseui=None):
self.conf = conf
self.baseui = baseui
self.ui = None
self.lastrefresh = 0
self.motd = None
self.refresh()
def refresh(self):
if self.ui:
refreshinterval = self.ui.configint('web', 'refreshinterval')
else:
item = configitems.coreitems['web']['refreshinterval']
refreshinterval = item.default
# refreshinterval <= 0 means to always refresh.
if (refreshinterval > 0 and
self.lastrefresh + refreshinterval > time.time()):
return
if self.baseui:
u = self.baseui.copy()
else:
u = uimod.ui.load()
u.setconfig('ui', 'report_untrusted', 'off', 'hgwebdir')
u.setconfig('ui', 'nontty', 'true', 'hgwebdir')
# displaying bundling progress bar while serving feels wrong and may
# break some wsgi implementations.
u.setconfig('progress', 'disable', 'true', 'hgweb')
if not isinstance(self.conf, (dict, list, tuple)):
map = {'paths': 'hgweb-paths'}
if not os.path.exists(self.conf):
raise error.Abort(_('config file %s not found!') % self.conf)
u.readconfig(self.conf, remap=map, trust=True)
paths = []
for name, ignored in u.configitems('hgweb-paths'):
for path in u.configlist('hgweb-paths', name):
paths.append((name, path))
elif isinstance(self.conf, (list, tuple)):
paths = self.conf
elif isinstance(self.conf, dict):
paths = self.conf.items()
repos = findrepos(paths)
for prefix, root in u.configitems('collections'):
prefix = util.pconvert(prefix)
for path in scmutil.walkrepos(root, followsym=True):
repo = os.path.normpath(path)
name = util.pconvert(repo)
if name.startswith(prefix):
name = name[len(prefix):]
repos.append((name.lstrip('/'), repo))
self.repos = repos
self.ui = u
encoding.encoding = self.ui.config('web', 'encoding')
self.style = self.ui.config('web', 'style')
self.templatepath = self.ui.config('web', 'templates', untrusted=False)
self.stripecount = self.ui.config('web', 'stripes')
if self.stripecount:
self.stripecount = int(self.stripecount)
self._baseurl = self.ui.config('web', 'baseurl')
prefix = self.ui.config('web', 'prefix')
if prefix.startswith('/'):
prefix = prefix[1:]
if prefix.endswith('/'):
prefix = prefix[:-1]
self.prefix = prefix
self.lastrefresh = time.time()
def run(self):
if not encoding.environ.get('GATEWAY_INTERFACE',
'').startswith("CGI/1."):
raise RuntimeError("This function is only intended to be "
"called while running as a CGI script.")
wsgicgi.launch(self)
def __call__(self, env, respond):
req = wsgirequest(env, respond)
return self.run_wsgi(req)
def read_allowed(self, ui, req):
"""Check allow_read and deny_read config options of a repo's ui object
to determine user permissions. By default, with neither option set (or
both empty), allow all users to read the repo. There are two ways a
user can be denied read access: (1) deny_read is not empty, and the
user is unauthenticated or deny_read contains user (or *), and (2)
allow_read is not empty and the user is not in allow_read. Return True
if user is allowed to read the repo, else return False."""
user = req.env.get('REMOTE_USER')
deny_read = ui.configlist('web', 'deny_read', untrusted=True)
if deny_read and (not user or ismember(ui, user, deny_read)):
return False
allow_read = ui.configlist('web', 'allow_read', untrusted=True)
# by default, allow reading if no allow_read option has been set
if (not allow_read) or ismember(ui, user, allow_read):
return True
return False
def run_wsgi(self, req):
profile = self.ui.configbool('profiling', 'enabled')
with profiling.profile(self.ui, enabled=profile):
try:
for r in self._runwsgi(req):
yield r
finally:
# There are known cycles in localrepository that prevent
# those objects (and tons of held references) from being
# collected through normal refcounting. We mitigate those
# leaks by performing an explicit GC on every request.
# TODO remove this once leaks are fixed.
# TODO only run this on requests that create localrepository
# instances instead of every request.
gc.collect()
def _runwsgi(self, req):
try:
self.refresh()
csp, nonce = cspvalues(self.ui)
if csp:
req.headers.append(('Content-Security-Policy', csp))
virtual = req.env.get("PATH_INFO", "").strip('/')
tmpl = self.templater(req, nonce)
ctype = tmpl('mimetype', encoding=encoding.encoding)
ctype = templater.stringify(ctype)
# a static file
if virtual.startswith('static/') or 'static' in req.form:
if virtual.startswith('static/'):
fname = virtual[7:]
else:
fname = req.form['static'][0]
static = self.ui.config("web", "static", None,
untrusted=False)
if not static:
tp = self.templatepath or templater.templatepaths()
if isinstance(tp, str):
tp = [tp]
static = [os.path.join(p, 'static') for p in tp]
staticfile(static, fname, req)
return []
# top-level index
repos = dict(self.repos)
if (not virtual or virtual == 'index') and virtual not in repos:
req.respond(HTTP_OK, ctype)
return self.makeindex(req, tmpl)
# nested indexes and hgwebs
if virtual.endswith('/index') and virtual not in repos:
subdir = virtual[:-len('index')]
if any(r.startswith(subdir) for r in repos):
req.respond(HTTP_OK, ctype)
return self.makeindex(req, tmpl, subdir)
def _virtualdirs():
# Check the full virtual path, each parent, and the root ('')
if virtual != '':
yield virtual
for p in util.finddirs(virtual):
yield p
yield ''
for virtualrepo in _virtualdirs():
real = repos.get(virtualrepo)
if real:
req.env['REPO_NAME'] = virtualrepo
try:
# ensure caller gets private copy of ui
repo = hg.repository(self.ui.copy(), real)
return hgweb_mod.hgweb(repo).run_wsgi(req)
except IOError as inst:
msg = encoding.strtolocal(inst.strerror)
raise ErrorResponse(HTTP_SERVER_ERROR, msg)
except error.RepoError as inst:
raise ErrorResponse(HTTP_SERVER_ERROR, bytes(inst))
# browse subdirectories
subdir = virtual + '/'
if [r for r in repos if r.startswith(subdir)]:
req.respond(HTTP_OK, ctype)
return self.makeindex(req, tmpl, subdir)
# prefixes not found
req.respond(HTTP_NOT_FOUND, ctype)
return tmpl("notfound", repo=virtual)
except ErrorResponse as err:
req.respond(err, ctype)
return tmpl('error', error=err.message or '')
finally:
tmpl = None
def makeindex(self, req, tmpl, subdir=""):
def archivelist(ui, nodeid, url):
allowed = ui.configlist("web", "allow_archive", untrusted=True)
archives = []
for typ, spec in hgweb_mod.archivespecs.iteritems():
if typ in allowed or ui.configbool("web", "allow" + typ,
untrusted=True):
archives.append({"type": typ, "extension": spec[2],
"node": nodeid, "url": url})
return archives
def rawentries(subdir="", **map):
descend = self.ui.configbool('web', 'descend')
collapse = self.ui.configbool('web', 'collapse')
seenrepos = set()
seendirs = set()
for name, path in self.repos:
if not name.startswith(subdir):
continue
name = name[len(subdir):]
directory = False
if '/' in name:
if not descend:
continue
nameparts = name.split('/')
rootname = nameparts[0]
if not collapse:
pass
elif rootname in seendirs:
continue
elif rootname in seenrepos:
pass
else:
directory = True
name = rootname
# redefine the path to refer to the directory
discarded = '/'.join(nameparts[1:])
# remove name parts plus accompanying slash
path = path[:-len(discarded) - 1]
try:
r = hg.repository(self.ui, path)
directory = False
except (IOError, error.RepoError):
pass
parts = [name]
parts.insert(0, '/' + subdir.rstrip('/'))
if req.env['SCRIPT_NAME']:
parts.insert(0, req.env['SCRIPT_NAME'])
url = re.sub(r'/+', '/', '/'.join(parts) + '/')
# show either a directory entry or a repository
if directory:
# get the directory's time information
try:
d = (get_mtime(path), util.makedate()[1])
except OSError:
continue
# add '/' to the name to make it obvious that
# the entry is a directory, not a regular repository
row = {'contact': "",
'contact_sort': "",
'name': name + '/',
'name_sort': name,
'url': url,
'description': "",
'description_sort': "",
'lastchange': d,
'lastchange_sort': d[1]-d[0],
'archives': [],
'isdirectory': True,
'labels': [],
}
seendirs.add(name)
yield row
continue
u = self.ui.copy()
try:
u.readconfig(os.path.join(path, '.hg', 'hgrc'))
except Exception as e:
u.warn(_('error reading %s/.hg/hgrc: %s\n') % (path, e))
continue
def get(section, name, default=uimod._unset):
return u.config(section, name, default, untrusted=True)
if u.configbool("web", "hidden", untrusted=True):
continue
if not self.read_allowed(u, req):
continue
# update time with local timezone
try:
r = hg.repository(self.ui, path)
except IOError:
u.warn(_('error accessing repository at %s\n') % path)
continue
except error.RepoError:
u.warn(_('error accessing repository at %s\n') % path)
continue
try:
d = (get_mtime(r.spath), util.makedate()[1])
except OSError:
continue
contact = get_contact(get)
description = get("web", "description")
seenrepos.add(name)
name = get("web", "name", name)
row = {'contact': contact or "unknown",
'contact_sort': contact.upper() or "unknown",
'name': name,
'name_sort': name,
'url': url,
'description': description or "unknown",
'description_sort': description.upper() or "unknown",
'lastchange': d,
'lastchange_sort': d[1]-d[0],
'archives': archivelist(u, "tip", url),
'isdirectory': None,
'labels': u.configlist('web', 'labels', untrusted=True),
}
yield row
sortdefault = None, False
def entries(sortcolumn="", descending=False, subdir="", **map):
rows = rawentries(subdir=subdir, **map)
if sortcolumn and sortdefault != (sortcolumn, descending):
sortkey = '%s_sort' % sortcolumn
rows = sorted(rows, key=lambda x: x[sortkey],
reverse=descending)
for row, parity in zip(rows, paritygen(self.stripecount)):
row['parity'] = parity
yield row
self.refresh()
sortable = ["name", "description", "contact", "lastchange"]
sortcolumn, descending = sortdefault
if 'sort' in req.form:
sortcolumn = req.form['sort'][0]
descending = sortcolumn.startswith('-')
if descending:
sortcolumn = sortcolumn[1:]
if sortcolumn not in sortable:
sortcolumn = ""
sort = [("sort_%s" % column,
"%s%s" % ((not descending and column == sortcolumn)
and "-" or "", column))
for column in sortable]
self.refresh()
self.updatereqenv(req.env)
return tmpl("index", entries=entries, subdir=subdir,
pathdef=hgweb_mod.makebreadcrumb('/' + subdir, self.prefix),
sortcolumn=sortcolumn, descending=descending,
**dict(sort))
def templater(self, req, nonce):
def motd(**map):
if self.motd is not None:
yield self.motd
else:
yield config('web', 'motd')
def config(section, name, default=uimod._unset, untrusted=True):
return self.ui.config(section, name, default, untrusted)
self.updatereqenv(req.env)
url = req.env.get('SCRIPT_NAME', '')
if not url.endswith('/'):
url += '/'
vars = {}
styles, (style, mapfile) = hgweb_mod.getstyle(req, config,
self.templatepath)
if style == styles[0]:
vars['style'] = style
start = r'&' if url[-1] == r'?' else r'?'
sessionvars = webutil.sessionvars(vars, start)
logourl = config('web', 'logourl')
logoimg = config('web', 'logoimg')
staticurl = config('web', 'staticurl') or url + 'static/'
if not staticurl.endswith('/'):
staticurl += '/'
defaults = {
"encoding": encoding.encoding,
"motd": motd,
"url": url,
"logourl": logourl,
"logoimg": logoimg,
"staticurl": staticurl,
"sessionvars": sessionvars,
"style": style,
"nonce": nonce,
}
tmpl = templater.templater.frommapfile(mapfile, defaults=defaults)
return tmpl
def updatereqenv(self, env):
if self._baseurl is not None:
name, port, path = geturlcgivars(self._baseurl, env['SERVER_PORT'])
env['SERVER_NAME'] = name
env['SERVER_PORT'] = port
env['SCRIPT_NAME'] = path