# acl.py - changeset access control 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, incorporated herein by reference.

#

'''hooks for controlling repository access

To use this hook, configure the acl extension in your hgrc like this:

  [extensions]

  hgext.acl =

  [hooks]

  pretxnchangegroup.acl = python:hgext.acl.hook

  [acl]

  # Check whether the source of incoming changes is in this list

  # ("serve" == ssh or http, "push", "pull", "bundle")

  sources = serve

  [acl.allow]

  # If acl.allow is not present, all users are allowed by default.

  # An empty acl.allow section means no users allowed.

  docs/** = doc_writer

  .hgtags = release_engineer

  [acl.deny]

  # If acl.deny is not present, no users are refused by default.

  # An empty acl.deny section means all users allowed.

  glob pattern = user4, user5

   ** = user6

'''

from mercurial.i18n import _

from mercurial import util, match

import getpass, urllib

def buildmatch(ui, repo, user, key):

    '''return tuple of (match function, list enabled).'''

    if not ui.has_section(key):

        ui.debug(_('acl: %s not enabled\n') % key)

        return None

    pats = [pat for pat, users in ui.configitems(key)

            if user in users.replace(',', ' ').split()]

    ui.debug(_('acl: %s enabled, %d entries for user %s\n') %

             (key, len(pats), user))

    if pats:

        return match.match(repo.root, '', pats)

    return match.exact(repo.root, '', [])

def hook(ui, repo, hooktype, node=None, source=None, **kwargs):

    if hooktype != 'pretxnchangegroup':

        raise util.Abort(_('config error - hook type "%s" cannot stop '

                           'incoming changesets') % hooktype)

    if source not in ui.config('acl', 'sources', 'serve').split():

        ui.debug(_('acl: changes have source "%s" - skipping\n') % source)

        return

    user = None

    if source == 'serve' and 'url' in kwargs:

        url = kwargs['url'].split(':')

        if url[0] == 'remote' and url[1].startswith('http'):

            user = urllib.unquote(url[3])

    if user is None:

        user = getpass.getuser()

    cfg = ui.config('acl', 'config')

    if cfg:

        ui.readconfig(cfg, sections = ['acl.allow', 'acl.deny'])

    allow = buildmatch(ui, repo, user, 'acl.allow')

    deny = buildmatch(ui, repo, user, 'acl.deny')

    for rev in xrange(repo[node], len(repo)):

        ctx = repo[rev]

        for f in ctx.files():

            if deny and deny(f):

                ui.debug(_('acl: user %s denied on %s\n') % (user, f))

                raise util.Abort(_('acl: access denied for changeset %s') % ctx)

            if allow and not allow(f):

                ui.debug(_('acl: user %s not allowed on %s\n') % (user, f))

                raise util.Abort(_('acl: access denied for changeset %s') % ctx)

        ui.debug(_('acl: allowing changeset %s\n') % ctx)