from vcs.exceptions import RepositoryError

    if not isinstance(repo, BaseRepository):

        raise Exception('You must pass an Repository '

                        'object as first argument got %s', type(repo))

    try:

        cs = repo.get_changeset(rev)

    except RepositoryError:

        from rhodecode.lib.utils import EmptyChangeset

        cs = EmptyChangeset(requested_revision=rev)

    return cs

def get_current_revision(quiet=False):

    """

    Returns tuple of (number, id) from repository containing this package

    or None if repository could not be found.

    :param quiet: prints error for fetching revision if True

    """

    try:

        from vcs import get_repo

        from vcs.utils.helpers import get_scm

        repopath = os.path.join(os.path.dirname(__file__), '..', '..')

        scm = get_scm(repopath)[0]

        repo = get_repo(path=repopath, alias=scm)

        tip = repo.get_changeset()

        return (tip.revision, tip.short_id)

        if not quiet:

            print ("Cannot retrieve rhodecode's revision. Original error "

                   "was: %s" % err)

        return None

try:

    import ldap

except ImportError:

    # means that python-ldap is not installed

    pass

class AuthLdap(object):

    def __init__(self, server, base_dn, port=389, bind_dn='', bind_pass='',

                 tls_kind='PLAIN', tls_reqcert='DEMAND', ldap_version=3,

                 ldap_filter='(&(objectClass=user)(!(objectClass=computer)))',

                 search_scope='SUBTREE',

                 attr_login='uid'):

        self.ldap_version = ldap_version

        ldap_server_type = 'ldap'

        self.TLS_KIND = tls_kind

        if self.TLS_KIND == 'LDAPS':

            port = port or 689

            ldap_server_type = ldap_server_type + 's'

        self.LDAP_SERVER_ADDRESS = server

        self.LDAP_SERVER_PORT = port

        #USE FOR READ ONLY BIND TO LDAP SERVER

        self.LDAP_BIND_DN = bind_dn

        self.LDAP_BIND_PASS = bind_pass

        self.LDAP_SERVER = "%s://%s:%s" % (ldap_server_type,

                                               self.LDAP_SERVER_ADDRESS,

                                               self.LDAP_SERVER_PORT)

        self.BASE_DN = base_dn

        self.LDAP_FILTER = ldap_filter

        self.attr_login = attr_login

    def authenticate_ldap(self, username, password):

        """Authenticate a user via LDAP and return his/her LDAP properties.

        Raises AuthenticationError if the credentials are rejected, or

        EnvironmentError if the LDAP server can't be reached.

        :param username: username

        :param password: password

        """

        from rhodecode.lib.helpers import chop_at

        uid = chop_at(username, "@%s" % self.LDAP_SERVER_ADDRESS)

        if "," in username:

            raise LdapUsernameError("invalid character in username: ,")

        try:

            ldap.set_option(ldap.OPT_REFERRALS, ldap.OPT_OFF)

            ldap.set_option(ldap.OPT_RESTART, ldap.OPT_ON)

            ldap.set_option(ldap.OPT_TIMEOUT, 20)

            ldap.set_option(ldap.OPT_NETWORK_TIMEOUT, 10)

            ldap.set_option(ldap.OPT_TIMELIMIT, 15)

            if self.TLS_KIND != 'PLAIN':

                ldap.set_option(ldap.OPT_X_TLS_REQUIRE_CERT, self.TLS_REQCERT)

            server = ldap.initialize(self.LDAP_SERVER)

            if self.ldap_version == 2:

                server.protocol = ldap.VERSION2

            else:

                server.protocol = ldap.VERSION3

            if self.TLS_KIND == 'START_TLS':

                server.start_tls_s()

            if self.LDAP_BIND_DN and self.LDAP_BIND_PASS:

                server.simple_bind_s(self.LDAP_BIND_DN, self.LDAP_BIND_PASS)

            filt = '(&%s(%s=%s))' % (self.LDAP_FILTER, self.attr_login,

                                     username)

            log.debug("Authenticating %r filt %s at %s", self.BASE_DN,

                      filt, self.LDAP_SERVER)

            lobjects = server.search_ext_s(self.BASE_DN, self.SEARCH_SCOPE,

            new_users_group = cls()

            for k, v in form_data.items():

                setattr(new_users_group, k, v)

            Session.add(new_users_group)

            Session.commit()

            return new_users_group

        except:

            log.error(traceback.format_exc())

            Session.rollback()

            raise

    @classmethod

    def update(cls, users_group_id, form_data):

        try:

            users_group = cls.get(users_group_id, cache=False)

            for k, v in form_data.items():

                if k == 'users_group_members':

                    users_group.members = []

                    Session.flush()

                    members_list = []

                    if v:

                        for u_id in set(v):

                    setattr(users_group, 'members', members_list)

                setattr(users_group, k, v)

            Session.add(users_group)

            Session.commit()

        except:

            log.error(traceback.format_exc())

            Session.rollback()

            raise

    @classmethod

    def delete(cls, users_group_id):

        try:

            # check if this group is not assigned to repo

            assigned_groups = UsersGroupRepoToPerm.query()\

                .filter(UsersGroupRepoToPerm.users_group_id ==

                        users_group_id).all()

            if assigned_groups:

                raise UsersGroupsAssignedException('Group assigned to %s' %

                                                   assigned_groups)

            users_group = cls.get(users_group_id, cache=False)