self.date = ''

        self.repository = repo

        self.requested_revision = requested_revision

        self.alias = alias

    @LazyProperty

    def raw_id(self):

        """

        Returns raw string identifying this changeset, useful for web

        representation.

        """

        return self._empty_cs

    @LazyProperty

    def branch(self):

        return get_backend(self.alias).DEFAULT_BRANCH_NAME

    @LazyProperty

    def short_id(self):

        return self.raw_id[:12]

    def get_file_changeset(self, path):

        return self

    def get_file_content(self, path):

        return u''

    def get_file_size(self, path):

        return 0

def map_groups(groups):

    """

    Checks for groups existence, and creates groups structures.

    It returns last group in structure

    :param groups: list of groups structure

    """

    sa = meta.Session

    parent = None

    group = None

    # last element is repo in nested groups structure

    groups = groups[:-1]

    rgm = ReposGroupModel(sa)

    for lvl, group_name in enumerate(groups):

        group_name = '/'.join(groups[:lvl] + [group_name])

        group = RepoGroup.get_by_group_name(group_name)

        desc = '%s group' % group_name

#        # WTF that doesn't work !?

#        if group is None:

#            group = rgm.create(group_name, desc, parent, just_db=True)

#            sa.commit()

        if group is None:

            group = RepoGroup(group_name, parent)

            group.group_description = desc

            sa.add(group)

            rgm._create_default_perms(group)

            sa.commit()

        parent = group

    return group

def repo2db_mapper(initial_repo_list, remove_obsolete=False):

    """

    maps all repos given in initial_repo_list, non existing repositories

    are created, if remove_obsolete is True it also check for db entries

    that are not in initial_repo_list and removes them.

    :param initial_repo_list: list of repositories found by scanning methods

    :param remove_obsolete: check for obsolete entries in database

    """

    from rhodecode.model.repo import RepoModel

    sa = meta.Session

    rm = RepoModel()

    user = sa.query(User).filter(User.admin == True).first()

    if user is None:

        raise Exception('Missing administrative account !')

    added = []

    # fixup groups paths to new format on the fly. Helps with migration from

    # old rhodecode versions also set permissions if they are not present !

    # TODO: remove this in future, before release

    def_usr = User.get_by_username('default')

    for g in RepoGroup.query().all():

        g.group_name = g.get_new_name(g.name)

        sa.add(g)

        # get default perm

        default = UserRepoGroupToPerm.query()\

            .filter(UserRepoGroupToPerm.group == g)\

            .filter(UserRepoGroupToPerm.user == def_usr)\

            .scalar()

        if default is None:

            log.debug('missing default permission for group %s adding' % g)

            ReposGroupModel()._create_default_perms(g)

    for name, repo in initial_repo_list.items():

        group = map_groups(name.split(Repository.url_sep()))

        if not rm.get_by_repo_name(name, cache=False):

            log.info('repository %s not found creating default' % name)

            added.append(name)