Original author and date, and relevant copyright and licensing information is below:

:created_on: May 6, 2012

:author: marcink

:copyright: (c) 2013 RhodeCode GmbH, and others.

:license: GPLv3, see LICENSE.md for more details.

"""

import logging

import re

import mercurial.unionrepo

from tg import request

from tg import tmpl_context as c

from tg.i18n import ugettext as _

from webob.exc import HTTPBadRequest, HTTPFound, HTTPNotFound

from kallithea.config.routing import url

from kallithea.controllers.changeset import _context_url, _ignorews_url

from kallithea.lib import diffs

from kallithea.lib import helpers as h

from kallithea.lib.auth import HasRepoPermissionLevelDecorator, LoginRequired

from kallithea.lib.base import BaseRepoController, render

from kallithea.lib.graphmod import graph_data

from kallithea.model.db import Repository

log = logging.getLogger(__name__)

class CompareController(BaseRepoController):

    def _before(self, *args, **kwargs):

        super(CompareController, self)._before(*args, **kwargs)

        # The base repository has already been retrieved.

        c.a_repo = c.db_repo

        # Retrieve the "changeset" repository (default: same as base).

        other_repo = request.GET.get('other_repo', None)

        if other_repo is None:

            c.cs_repo = c.a_repo

        else:

            c.cs_repo = Repository.get_by_repo_name(other_repo)

            if c.cs_repo is None:

                msg = _('Could not find other repository %s') % other_repo

                h.flash(msg, category='error')

                raise HTTPFound(location=url('compare_home', repo_name=c.a_repo.repo_name))

    @staticmethod

    def _get_changesets(alias, org_repo, org_rev, other_repo, other_rev):

        """

        Returns lists of changesets that can be merged from org_repo@org_rev

        to other_repo@other_rev

        ... and the other way

        ... and the ancestors that would be used for merge

        :param org_repo: repo object, that is most likely the original repo we forked from

        :param org_rev: the revision we want our compare to be made

        :param other_repo: repo object, most likely the fork of org_repo. It has

            all changesets that we need to obtain

        :param other_rev: revision we want out compare to be made on other_repo

        """

        ancestors = None

        if org_rev == other_rev:

            org_changesets = []

            other_changesets = []

        elif alias == 'hg':

            # case two independent repos

            if org_repo != other_repo:

                hgrepo = mercurial.unionrepo.makeunionrepository(other_repo.baseui,

                # all ancestors of other_rev will be in other_repo and

                # rev numbers from hgrepo can be used in other_repo - org_rev ancestors cannot

            # no remote compare do it on the same repository

            else:

                hgrepo = other_repo._repo

            ancestors = [ascii_str(hgrepo[ancestor].hex()) for ancestor in

                         hgrepo.revs(b"id(%s) & ::id(%s)", ascii_bytes(other_rev), ascii_bytes(org_rev))]

            if ancestors:

                log.debug("shortcut found: %s is already an ancestor of %s", other_rev, org_rev)

            else:

                log.debug("no shortcut found: %s is not an ancestor of %s", other_rev, org_rev)

                ancestors = [ascii_str(hgrepo[ancestor].hex()) for ancestor in

                             hgrepo.revs(b"heads(::id(%s) & ::id(%s))", ascii_bytes(org_rev), ascii_bytes(other_rev))] # FIXME: expensive!

            other_changesets = [

                other_repo.get_changeset(rev)

                for rev in hgrepo.revs(

                    b"ancestors(id(%s)) and not ancestors(id(%s)) and not id(%s)",

                    ascii_bytes(other_rev), ascii_bytes(org_rev), ascii_bytes(org_rev))

            ]

            org_changesets = [

                org_repo.get_changeset(ascii_str(hgrepo[rev].hex()))

                c.a_branch_name = c.a_ref_name

                if c.a_ref_type != 'branch':

                    try:

                        c.a_branch_name = other_scm_instance.get_changeset(c.a_ref_name).branch # use ref_type ?

                    except EmptyRepositoryError:

                        c.a_branch_name = 'null' # not a branch name ... but close enough

                # candidates: descendants of old head that are on the right branch

                #             and not are the old head itself ...

                #             and nothing at all if old head is a descendant of target ref name

                if not c.is_range and other_scm_instance._repo.revs('present(%s)::&%s', c.cs_ranges[-1].raw_id, c.a_branch_name):

                    c.update_msg = _('This pull request has already been merged to %s.') % c.a_branch_name

                elif c.pull_request.is_closed():

                    c.update_msg = _('This pull request has been closed and can not be updated.')

                else: # look for descendants of PR head on source branch in org repo

                    avail_revs = org_scm_instance._repo.revs('%s:: & branch(%s)',

                                                             revs[0], c.cs_branch_name)

                    if len(avail_revs) > 1: # more than just revs[0]

                        # also show changesets that not are descendants but would be merged in

                        targethead = other_scm_instance.get_changeset(c.a_branch_name).raw_id

                        if org_scm_instance.path != other_scm_instance.path:

                            # Note: org_scm_instance.path must come first so all

                            # valid revision numbers are 100% org_scm compatible

                            # - both for avail_revs and for revset results

                            hgrepo = mercurial.unionrepo.makeunionrepository(org_scm_instance.baseui,

                        else:

                            hgrepo = org_scm_instance._repo

                        show = set(hgrepo.revs('::%ld & !::parents(%s) & !::%s',

                                               avail_revs, revs[0], targethead))

                        if show:

                            c.update_msg = _('The following additional changes are available on %s:') % c.cs_branch_name

                        else:

                            c.update_msg = _('No additional changesets found for iterating on this pull request.')

                    else:

                        show = set()

                        avail_revs = set() # drop revs[0]

                        c.update_msg = _('No additional changesets found for iterating on this pull request.')

                    # TODO: handle branch heads that not are tip-most

                    brevs = org_scm_instance._repo.revs('%s - %ld - %s', c.cs_branch_name, avail_revs, revs[0])

                    if brevs:

                        # also show changesets that are on branch but neither ancestors nor descendants

                        show.update(org_scm_instance._repo.revs('::%ld - ::%ld - ::%s', brevs, avail_revs, c.a_branch_name))

                        show.add(revs[0]) # make sure graph shows this so we can see how they relate

                        c.update_msg_other = _('Note: Branch %s has another head: %s.') % (c.cs_branch_name,

                            h.short_id(org_scm_instance.get_changeset((max(brevs))).raw_id))

                    avail_show = sorted(show, reverse=True)

    or Python's own OpenSSL wrapper on windows

    :param password: password to hash

    """

    if is_windows:

        return hashlib.sha256(password).hexdigest()

    elif is_unix:

        import bcrypt

        return ascii_str(bcrypt.hashpw(safe_bytes(password), bcrypt.gensalt(10)))

    else:

        raise Exception('Unknown or unsupported platform %s'

                        % __platform__)

def check_password(password, hashed):

    """

    Checks matching password with it's hashed value, runs different

    implementation based on platform it runs on

    :param password: password

    :param hashed: password in hashed form

    """

    if is_windows:

    elif is_unix:

        import bcrypt

        try:

            return bcrypt.checkpw(safe_bytes(password), ascii_bytes(hashed))

        except ValueError as e:

            # bcrypt will throw ValueError 'Invalid hashed_password salt' on all password errors

            log.error('error from bcrypt checking password: %s', e)

            return False

    else:

        raise Exception('Unknown or unsupported platform %s'

                        % __platform__)

def _cached_perms_data(user_id, user_is_admin):

    RK = 'repositories'

    GK = 'repositories_groups'

    UK = 'user_groups'

    GLOBAL = 'global'

    PERM_WEIGHTS = Permission.PERM_WEIGHTS

    permissions = {RK: {}, GK: {}, UK: {}, GLOBAL: set()}

    def bump_permission(kind, key, new_perm):

        """Add a new permission for kind and key.

        Assuming the permissions are comparable, set the new permission if it

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

"""

kallithea.lib.hooks

~~~~~~~~~~~~~~~~~~~

Hooks run by Kallithea

This file was forked by the Kallithea project in July 2014.

Original author and date, and relevant copyright and licensing information is below:

:created_on: Aug 6, 2010

:author: marcink

:copyright: (c) 2013 RhodeCode GmbH, and others.

:license: GPLv3, see LICENSE.md for more details.

"""

import os

import time

import mercurial.scmutil

from kallithea.lib import helpers as h

from kallithea.lib.exceptions import UserCreationError

from kallithea.lib.utils import action_logger, make_ui, setup_cache_regions

from kallithea.lib.vcs.backends.base import EmptyChangeset

from kallithea.model.db import Repository, User

def _get_scm_size(alias, root_path):

    if not alias.startswith('.'):

        alias += '.'

    size_scm, size_root = 0, 0

    for path, dirs, files in os.walk(safe_str(root_path)):

        if path.find(alias) != -1:

            for f in files:

                try:

                    size_scm += os.path.getsize(os.path.join(path, f))

                except OSError:

                    pass

        else:

            for f in files:

                try:

                    size_root += os.path.getsize(os.path.join(path, f))

                except OSError:

                    pass

    size_scm_f = h.format_byte_size(size_scm)

    size_root_f = h.format_byte_size(size_root)

    size_total_f = h.format_byte_size(size_root + size_scm)

    return size_scm_f, size_root_f, size_total_f

def repo_size(ui, repo, hooktype=None, **kwargs):

    """Show size of Mercurial repository, to be called after push."""

    size_hg_f, size_root_f, size_total_f = _get_scm_size('.hg', repo.root)

    last_cs = repo[len(repo) - 1]

    msg = ('Repository size .hg: %s Checkout: %s Total: %s\n'

           'Last revision is now r%s:%s\n') % (

        size_hg_f, size_root_f, size_total_f, last_cs.rev(), ascii_str(last_cs.hex())[:12]

    )

def log_pull_action(ui, repo, **kwargs):

    """Logs user last pull action

    Called as Mercurial hook outgoing.pull_logger or from Kallithea before invoking Git.

    Does *not* use the action from the hook environment but is always 'pull'.

    """

    ex = get_hook_environment()

    user = User.get_by_username(ex.username)

    action = 'pull'

    action_logger(user, action, ex.repository, ex.ip, commit=True)

    # extension hook call

    from kallithea import EXTENSIONS

    callback = getattr(EXTENSIONS, 'PULL_HOOK', None)

    if callable(callback):

        kw = {}

        kw.update(ex)

        callback(**kw)

    return 0

    # the post push hook should never use the cached instance

    scm_repo = repo.scm_instance_no_cache()

    rev_data = []

    for l in git_stdin_lines:

        old_rev, new_rev, ref = l.strip().split(' ')

        _ref_data = ref.split('/')

        if _ref_data[1] in ['tags', 'heads']:

            rev_data.append({'old_rev': old_rev,

                             'new_rev': new_rev,

                             'ref': ref,

                             'type': _ref_data[1],

                             'name': '/'.join(_ref_data[2:])})

    git_revs = []

    for push_ref in rev_data:

        _type = push_ref['type']

        if _type == 'heads':

            if push_ref['old_rev'] == EmptyChangeset().raw_id:

                # update the symbolic ref if we push new repo

                if scm_repo.is_empty():

                    scm_repo._repo.refs.set_symbolic_ref(

                        b'HEAD',

                # build exclude list without the ref

                cmd = ['for-each-ref', '--format=%(refname)', 'refs/heads/*']

                stdout = scm_repo.run_git_command(cmd)

                ref = push_ref['ref']

                heads = [head for head in stdout.splitlines() if head != ref]

                # now list the git revs while excluding from the list

                cmd = ['log', push_ref['new_rev'], '--reverse', '--pretty=format:%H']

                cmd.append('--not')

                cmd.extend(heads) # empty list is ok

                stdout = scm_repo.run_git_command(cmd)

                git_revs += stdout.splitlines()

            elif push_ref['new_rev'] == EmptyChangeset().raw_id:

                # delete branch case

                git_revs += ['delete_branch=>%s' % push_ref['name']]

            else:

                cmd = ['log', '%(old_rev)s..%(new_rev)s' % push_ref,

                       '--reverse', '--pretty=format:%H']

                stdout = scm_repo.run_git_command(cmd)

                git_revs += stdout.splitlines()

        elif _type == 'tags':

            git_revs += ['tag=>%s' % push_ref['name']]

    process_pushed_raw_ids(git_revs)

    return 0

# Almost exactly like Mercurial contrib/hg-ssh:

def rejectpush(ui, **kwargs):

    """Mercurial hook to be installed as pretxnopen and prepushkey for read-only repos"""

    ex = get_hook_environment()

    return 1

kallithea.lib.middleware.simplehg

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

SimpleHg middleware for handling Mercurial protocol requests (push/clone etc.).

It's implemented with basic auth function

This file was forked by the Kallithea project in July 2014.

Original author and date, and relevant copyright and licensing information is below:

:created_on: Apr 28, 2010

:author: marcink

:copyright: (c) 2013 RhodeCode GmbH, and others.

:license: GPLv3, see LICENSE.md for more details.

"""

import logging

import os

import urllib

import mercurial.hgweb

from kallithea.lib.base import BaseVCSController, get_path_info

from kallithea.lib.utils import make_ui

log = logging.getLogger(__name__)

def get_header_hgarg(environ):

    """Decode the special Mercurial encoding of big requests over multiple headers.

    >>> get_header_hgarg({})

    ''

    >>> get_header_hgarg({'HTTP_X_HGARG_0': ' ', 'HTTP_X_HGARG_1': 'a','HTTP_X_HGARG_2': '','HTTP_X_HGARG_3': 'b+c %20'})

    'ab+c %20'

    """

    chunks = []

    i = 1

    while True:

        v = environ.get('HTTP_X_HGARG_%d' % i)

        if v is None:

            break

        chunks.append(v)

        i += 1

    return ''.join(chunks)

cmd_mapping = {

                        if not hgarg.startswith('cmds='):

                            action = 'push' # paranoid and safe

                            break

                        action = 'pull'

                        for cmd_arg in hgarg[5:].split(';'):

                            cmd, _args = urllib.unquote_plus(cmd_arg).split(' ', 1)

                            op = cmd_mapping.get(cmd, 'push')

                            if op != 'pull':

                                assert op == 'push'

                                action = 'push'

                                break

                    else:

                        action = cmd_mapping.get(cmd, 'push')

                    break # only process one cmd

        return parsed_request

    def _make_app(self, parsed_request):

        """

        Make an hgweb wsgi application.

        """

        str_repo_name = safe_str(parsed_request.repo_name)

        repo_path = os.path.join(safe_str(self.basepath), str_repo_name)

        baseui = make_ui(repo_path=repo_path)

        def wrapper_app(environ, start_response):

            environ['REPO_NAME'] = str_repo_name # used by mercurial.hgweb.hgweb

            return hgweb_app(environ, start_response)

        return wrapper_app

    sa = meta.Session()

    for ui_ in sa.query(Ui).all():

        if ui_.ui_active:

            log.debug('config from db: [%s] %s=%r', ui_.ui_section,

                      ui_.ui_key, ui_.ui_value)

            baseui.setconfig(ascii_bytes(ui_.ui_section), ascii_bytes(ui_.ui_key),

                             b'' if ui_.ui_value is None else safe_bytes(ui_.ui_value))

    # force set push_ssl requirement to False, Kallithea handles that

    baseui.setconfig(b'web', b'push_ssl', False)

    baseui.setconfig(b'web', b'allow_push', b'*')

    # prevent interactive questions for ssh password / passphrase

    ssh = baseui.config(b'ui', b'ssh', default=b'ssh')

    baseui.setconfig(b'ui', b'ssh', b'%s -oBatchMode=yes -oIdentitiesOnly=yes' % ssh)

    # push / pull hooks

    baseui.setconfig(b'hooks', b'changegroup.kallithea_log_push_action', b'python:kallithea.lib.hooks.log_push_action')

    baseui.setconfig(b'hooks', b'outgoing.kallithea_log_pull_action', b'python:kallithea.lib.hooks.log_pull_action')

    if repo_path is not None:

        hgrc_path = os.path.join(repo_path, '.hg', 'hgrc')

        if os.path.isfile(hgrc_path):

            log.debug('reading hgrc from %s', hgrc_path)

            cfg = mercurial.config.config()

            for section in ui_sections:

                for k, v in cfg.items(section):

                    log.debug('config from file: [%s] %s=%s', section, k, v)

                    baseui.setconfig(ascii_bytes(section), ascii_bytes(k), safe_bytes(v))

        else:

            log.debug('hgrc file is not present at %s, skipping...', hgrc_path)

    return baseui

def set_app_settings(config):

    """

    Updates app config with new settings from database

    :param config:

    """

    hgsettings = Setting.get_app_settings()

    for k, v in hgsettings.items():

        config[k] = v

def set_vcs_config(config):

    """

    Patch VCS config with some Kallithea specific stuff

                curtree[node_path] = node.mode, blob.id

                new_trees.append(curtree)

                for dirname in reversed_dirnames[:-1]:

                    newtree = objects.Tree()

                    #newtree.add(stat.S_IFDIR, dirname, curtree.id)

                    newtree[dirname] = stat.S_IFDIR, curtree.id

                    new_trees.append(newtree)

                    curtree = newtree

                parent[reversed_dirnames[-1]] = stat.S_IFDIR, curtree.id

            else:

                parent.add(name=node_path, mode=node.mode, hexsha=blob.id)

            new_trees.append(parent)

            # Update ancestors

            for parent, tree, path in reversed([(a[1], b[1], b[0]) for a, b in

                zip(ancestors, ancestors[1:])]

            ):

                parent[path] = stat.S_IFDIR, tree.id

                object_store.add_object(tree)

            object_store.add_object(blob)

            for tree in new_trees:

                object_store.add_object(tree)

        for node in self.removed:

            tree = commit_tree

            trees = [tree]

            # Traverse deep into the forest...

            for path in paths:

                try:

                    obj = self.repository._repo[tree[path][1]]

                    if isinstance(obj, objects.Tree):

                        trees.append(obj)

                        tree = obj

                except KeyError:

                    break

            # Cut down the blob and all rotten trees on the way back...

            for path, tree in reversed(zip(paths, trees)):

                del tree[path]

                if tree:

                    # This tree still has elements - don't remove it or any

                    # of it's parents

                    break

        object_store.add_object(commit_tree)

        # Create commit

        commit = objects.Commit()

        commit.tree = commit_tree.id

        commit.parents = [p._commit.id for p in self.parents if p]

        commit.author = commit.committer = safe_bytes(author)

        commit.encoding = ENCODING

        commit.message = safe_bytes(message)

        # Compute date

        if date is None:

            date = time.time()

        elif isinstance(date, datetime.datetime):

            date = time.mktime(date.timetuple())

        author_time = kwargs.pop('author_time', date)

        commit.commit_time = int(date)

        commit.author_time = int(author_time)

        tz = time.timezone

        author_tz = kwargs.pop('author_timezone', tz)

        commit.commit_timezone = tz

        commit.author_timezone = author_tz

        object_store.add_object(commit)

        # Update vcs repository object & recreate dulwich repo

        repo.refs[ref] = commit.id

        self.repository.revisions.append(ascii_str(commit.id))

        # invalidate parsed refs after commit

        self.repository._parsed_refs = self.repository._get_parsed_refs()

        tip = self.repository.get_changeset()

        self.reset()

        return tip

    def _get_missing_trees(self, path, root_tree):

        """

        Creates missing ``Tree`` objects for the given path.

        :param path: path given as a string. It may be a path to a file node

          (i.e. ``foo/bar/baz.txt``) or directory path - in that case it must

          end with slash (i.e. ``foo/bar/``).

        :param root_tree: ``dulwich.objects.Tree`` object from which we start

          traversing (should be commit's root tree)

        """

        dirpath = posixpath.split(path)[0]

        dirs = dirpath.split('/')

        if not dirs or dirs == ['']:

            return []

        def get_tree_for_dir(tree, dirname):

    :created_on: Apr 8, 2010

    :copyright: (c) 2010-2011 by Marcin Kuzminski, Lukasz Balcerzak.

"""

import errno

import logging

import os

import re

import time

import urllib

import urllib2

from collections import OrderedDict

import mercurial.url  # import httpbasicauthhandler, httpdigestauthhandler

import mercurial.util  # import url as hg_url

from dulwich.config import ConfigFile

from dulwich.objects import Tag

from dulwich.repo import NotGitRepository, Repo

from kallithea.lib.vcs import subprocessio

from kallithea.lib.vcs.backends.base import BaseRepository, CollectionGenerator

from kallithea.lib.vcs.conf import settings

from kallithea.lib.vcs.exceptions import (

    BranchDoesNotExistError, ChangesetDoesNotExistError, EmptyRepositoryError, RepositoryError, TagAlreadyExistError, TagDoesNotExistError)

from kallithea.lib.vcs.utils.lazy import LazyProperty

from kallithea.lib.vcs.utils.paths import abspath, get_user_home

from .changeset import GitChangeset

from .inmemory import GitInMemoryChangeset

from .workdir import GitWorkdir

SHA_PATTERN = re.compile(r'^([0-9a-fA-F]{12}|[0-9a-fA-F]{40})$')

log = logging.getLogger(__name__)

class GitRepository(BaseRepository):

    """

    Git repository backend.

    """

    DEFAULT_BRANCH_NAME = 'master'

    scm = 'git'

    def __init__(self, repo_path, create=False, src_url=None,

                 update_after_clone=False, bare=False):

        self.path = safe_unicode(abspath(repo_path))

        return safe_unicode(stdout)

    @classmethod

    def _check_url(cls, url):

        """

        Function will check given url and try to verify if it's a valid

        link. Sometimes it may happened that git will issue basic

        auth request that can cause whole API to hang when used from python

        or other external calls.

        On failures it'll raise urllib2.HTTPError, exception is also thrown

        when the return code is non 200

        """

        # check first if it's not an local url

        if os.path.isdir(url) or url.startswith('file:'):

            return True

        if url.startswith('git://'):

            return True

        if '+' in url[:url.find('://')]:

            url = url[url.find('+') + 1:]

        handlers = []

        test_uri, authinfo = url_obj.authinfo()

        if not test_uri.endswith('info/refs'):

            test_uri = test_uri.rstrip('/') + '/info/refs'

        url_obj.passwd = b'*****'

        cleaned_uri = str(url_obj)

        if authinfo:

            # create a password manager

            passmgr = urllib2.HTTPPasswordMgrWithDefaultRealm()

            passmgr.add_password(*authinfo)

            handlers.extend((mercurial.url.httpbasicauthhandler(passmgr),

                             mercurial.url.httpdigestauthhandler(passmgr)))

        o = urllib2.build_opener(*handlers)

        o.addheaders = [('User-Agent', 'git/1.7.8.0')]  # fake some git

        req = urllib2.Request(

            "%s?%s" % (

                test_uri,

                urllib.urlencode({"service": 'git-upload-pack'})

            ))

        Given any revision identifier, returns a 40 char string with revision hash.

        """

        if self._empty:

            raise EmptyRepositoryError("There are no changesets yet")

        if revision in (None, '', 'tip', 'HEAD', 'head', -1):

            revision = -1

        if isinstance(revision, int):

            try:

                return self.revisions[revision]

            except IndexError:

                msg = "Revision %r does not exist for %s" % (revision, self.name)

                raise ChangesetDoesNotExistError(msg)

        if isinstance(revision, (str, unicode)):

            if revision.isdigit() and (len(revision) < 12 or len(revision) == revision.count('0')):

                try:

                    return self.revisions[int(revision)]

                except IndexError:

                    msg = "Revision %r does not exist for %s" % (revision, self)

                    raise ChangesetDoesNotExistError(msg)

            # get by branch/tag name

            if _ref_revision:  # and _ref_revision[1] in [b'H', b'RH', b'T']:

                return ascii_str(_ref_revision[0])

            if revision in self.revisions:

                return revision

            # maybe it's a tag ? we don't have them in self.revisions

            if revision in self.tags.values():

                return revision

            if SHA_PATTERN.match(revision):

                msg = "Revision %r does not exist for %s" % (revision, self.name)

                raise ChangesetDoesNotExistError(msg)

        raise ChangesetDoesNotExistError("Given revision %r not recognized" % revision)

    def get_ref_revision(self, ref_type, ref_name):

        """

        Returns ``GitChangeset`` object representing repository's

        changeset at the given ``revision``.

        """

        return self._get_revision(ref_name)

    def _get_archives(self, archive_name='tip'):

        sortkey = lambda ctx: ctx[0]

        _tags = [(key, ascii_str(sha))

                 for key, (sha, type_) in self._parsed_refs.iteritems() if type_ == b'T']

        return OrderedDict(sorted(_tags, key=sortkey, reverse=True))

    def tag(self, name, user, revision=None, message=None, date=None,

            **kwargs):

        """

        Creates and returns a tag for the given ``revision``.

        :param name: name for new tag

        :param user: full username, i.e.: "Joe Doe <joe.doe@example.com>"

        :param revision: changeset id for which new tag would be created

        :param message: message of the tag's commit

        :param date: date of tag's commit

        :raises TagAlreadyExistError: if tag with same name already exists

        """

        if name in self.tags:

            raise TagAlreadyExistError("Tag %s already exists" % name)

        changeset = self.get_changeset(revision)

        message = message or "Added tag %s for commit %s" % (name,

            changeset.raw_id)

        self._parsed_refs = self._get_parsed_refs()

        self.tags = self._get_tags()

        return changeset

    def remove_tag(self, name, user, message=None, date=None):

        """

        Removes tag with the given ``name``.

        :param name: name of the tag to be removed

        :param user: full username, i.e.: "Joe Doe <joe.doe@example.com>"

        :param message: message of the tag's removal commit

        :param date: date of tag's removal commit

        :raises TagDoesNotExistError: if tag with given name does not exists

        """

        if name not in self.tags:

            raise TagDoesNotExistError("Tag %s does not exist" % name)

        # self._repo.refs is a DiskRefsContainer, and .path gives the full absolute path of '.git'

        tagpath = os.path.join(self._repo.refs.path, 'refs', 'tags', name)

        try:

            os.remove(tagpath)

            self._parsed_refs = self._get_parsed_refs()

            self.tags = self._get_tags()

import os

import posixpath

import mercurial.archival

import mercurial.node

import mercurial.obsutil

from kallithea.lib.vcs.backends.base import BaseChangeset

from kallithea.lib.vcs.conf import settings

from kallithea.lib.vcs.exceptions import ChangesetDoesNotExistError, ChangesetError, ImproperArchiveTypeError, NodeDoesNotExistError, VCSError

from kallithea.lib.vcs.nodes import (

    AddedFileNodesGenerator, ChangedFileNodesGenerator, DirNode, FileNode, NodeKind, RemovedFileNodesGenerator, RootNode, SubModuleNode)

from kallithea.lib.vcs.utils.lazy import LazyProperty

from kallithea.lib.vcs.utils.paths import get_dirs_for_path

class MercurialChangeset(BaseChangeset):

    """

    Represents state of the repository at a revision.

    """

    def __init__(self, repository, revision):

        self.repository = repository

        assert isinstance(revision, basestring), repr(revision)

        self._ctx = repository._repo[ascii_bytes(revision)]

        self.raw_id = ascii_str(self._ctx.hex())

        self.revision = self._ctx._rev

        self.nodes = {}

    @LazyProperty

    def tags(self):

        return [safe_unicode(tag) for tag in self._ctx.tags()]

    @LazyProperty

    def branch(self):

        return safe_unicode(self._ctx.branch())

        Paths are stored without trailing slash so we need to get rid off it if