# we didn't override our tmpl from **overrides

        if not uri_tmpl:

            uri_tmpl = self.DEFAULT_CLONE_URI

            try:

                from pylons import tmpl_context as c

                uri_tmpl = c.clone_uri_tmpl

            except AttributeError:

                # in any case if we call this outside of request context,

                # ie, not having tmpl_context set up

                pass

        return get_clone_url(uri_tmpl=uri_tmpl,

                             qualified_home_url=qualified_home_url,

                             repo_name=self.repo_name,

                             repo_id=self.repo_id, **override)

    def set_state(self, state):

        self.repo_state = state

        Session().add(self)

    #==========================================================================

    # SCM PROPERTIES

    #==========================================================================

    def get_changeset(self, rev=None):

        return get_changeset_safe(self.scm_instance, rev)

    def get_landing_changeset(self):

        """

        Returns landing changeset, or if that doesn't exist returns the tip

        """

        _rev_type, _rev = self.landing_rev

        cs = self.get_changeset(_rev)

        if isinstance(cs, EmptyChangeset):

            return self.get_changeset()

        return cs

    def update_changeset_cache(self, cs_cache=None):

        """

        Update cache of last changeset for repository, keys should be::

            short_id

            raw_id

            revision

            message

            date

            author

        :param cs_cache:

        """

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

        if cs_cache is None:

            cs_cache = EmptyChangeset()

            # use no-cache version here

            scm_repo = self.scm_instance_no_cache()

            if scm_repo:

                cs_cache = scm_repo.get_changeset()

        if isinstance(cs_cache, BaseChangeset):

            cs_cache = cs_cache.__json__()

        if (not self.changeset_cache or cs_cache['raw_id'] != self.changeset_cache['raw_id']):

            _default = datetime.datetime.fromtimestamp(0)

            last_change = cs_cache.get('date') or _default

            log.debug('updated repo %s with new cs cache %s',

                      self.repo_name, cs_cache)

            self.updated_on = last_change

            self.changeset_cache = cs_cache

            Session().add(self)

            Session().commit()

        else:

            log.debug('changeset_cache for %s already up to date with %s',

                      self.repo_name, cs_cache['raw_id'])

    @property

    def tip(self):

        return self.get_changeset('tip')

    @property

    def author(self):

        return self.tip.author

    @property

    def last_change(self):

        return self.scm_instance.last_change

    def get_comments(self, revisions=None):

        """

        Returns comments for this repository grouped by revisions

        :param revisions: filter query by revisions only

        """

        cmts = ChangesetComment.query()\

            .filter(ChangesetComment.repo == self)

        if revisions is not None:

            if not revisions:

                return [] # don't use sql 'in' on empty set

            cmts = cmts.filter(ChangesetComment.revision.in_(revisions))

        grouped = collections.defaultdict(list)

        for cmt in cmts.all():

            grouped[cmt.revision].append(cmt)

        return grouped

    def statuses(self, revisions):

        """

        Returns statuses for this repository.

        PRs without any votes do _not_ show up as unreviewed.

        :param revisions: list of revisions to get statuses for

        """

        if not revisions:

            return {}

        statuses = ChangesetStatus.query()\

            .filter(ChangesetStatus.repo == self)\

            .filter(ChangesetStatus.version == 0)\

            .filter(ChangesetStatus.revision.in_(revisions))

        grouped = {}

        for stat in statuses.all():

            pr_id = pr_nice_id = pr_repo = None

            if stat.pull_request:

                pr_id = stat.pull_request.pull_request_id

                pr_nice_id = PullRequest.make_nice_id(pr_id)

                pr_repo = stat.pull_request.other_repo.repo_name

            grouped[stat.revision] = [str(stat.status), stat.status_lbl,

                                      pr_id, pr_repo, pr_nice_id]

        return grouped

    def _repo_size(self):

        from kallithea.lib import helpers as h

        log.debug('calculating repository size...')

        return h.format_byte_size(self.scm_instance.size)

    #==========================================================================

    # SCM CACHE INSTANCE

    #==========================================================================

    def set_invalidate(self):

        """

        Mark caches of this repo as invalid.

        """

        CacheInvalidation.set_invalidate(self.repo_name)

    def scm_instance_no_cache(self):

        return self.__get_instance()

    @property

    def scm_instance(self):

        import kallithea

        full_cache = str2bool(kallithea.CONFIG.get('vcs_full_cache'))

        if full_cache:

            return self.scm_instance_cached()

        return self.__get_instance()

    def scm_instance_cached(self, valid_cache_keys=None):

        @cache_region('long_term')

        def _c(repo_name):

            return self.__get_instance()

        rn = self.repo_name

        valid = CacheInvalidation.test_and_set_valid(rn, None, valid_cache_keys=valid_cache_keys)

        if not valid:

            log.debug('Cache for %s invalidated, getting new object', rn)

            region_invalidate(_c, None, rn)

        else:

            log.debug('Getting scm_instance of %s from cache', rn)

        return _c(rn)

    def __get_instance(self):

        repo_full_path = self.repo_full_path

        alias = get_scm(safe_str(repo_full_path))[0]

        log.debug('Creating instance of %s repository from %s',

                  alias, repo_full_path)

        backend = get_backend(alias)

        if alias == 'hg':

            repo = backend(safe_str(repo_full_path), create=False,

                           baseui=self._ui)

        else:

            repo = backend(repo_full_path, create=False)

        return repo

    def __json__(self):

        return dict(landing_rev = self.landing_rev)

class RepoGroup(Base, BaseModel):

    __tablename__ = 'groups'

    __table_args__ = (

        UniqueConstraint('group_name', 'group_parent_id'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True},

    )

    __mapper_args__ = {'order_by': 'group_name'}

    SEP = ' » '

    group_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    group_name = Column(String(255, convert_unicode=False), nullable=False, unique=True, default=None)

    group_parent_id = Column(Integer(), ForeignKey('groups.group_id'), nullable=True, unique=None, default=None)

    group_description = Column(String(10000, convert_unicode=False), nullable=True, unique=None, default=None)

    enable_locking = Column(Boolean(), nullable=False, unique=None, default=False)

    user_id = Column(Integer(), ForeignKey('users.user_id'), nullable=False, unique=False, default=None)

    created_on = Column(DateTime(timezone=False), nullable=False, default=datetime.datetime.now)

    repo_group_to_perm = relationship('UserRepoGroupToPerm', cascade='all', order_by='UserRepoGroupToPerm.group_to_perm_id')

    users_group_to_perm = relationship('UserGroupRepoGroupToPerm', cascade='all')

    parent_group = relationship('RepoGroup', remote_side=group_id)

    user = relationship('User')

    def __init__(self, group_name='', parent_group=None):

        self.group_name = group_name

        self.parent_group = parent_group

    def __unicode__(self):

        return u"<%s('id:%s:%s')>" % (self.__class__.__name__, self.group_id,

                                      self.group_name)

    @classmethod

    def _generate_choice(cls, repo_group):

        """Return tuple with group_id and name as html literal"""

        from webhelpers.html import literal

        if repo_group is None:

            return (-1, u'-- %s --' % _('top level'))

        return repo_group.group_id, literal(cls.SEP.join(repo_group.full_path_splitted))

    @classmethod

    def groups_choices(cls, groups):

        """Return tuples with group_id and name as html literal."""

        return sorted((cls._generate_choice(g) for g in groups),

                      key=lambda c: c[1].split(cls.SEP))

    @classmethod

    def url_sep(cls):

        return URL_SEP

    @classmethod

    def get_by_group_name(cls, group_name, cache=False, case_insensitive=False):

        if case_insensitive:

            gr = cls.query()\

                .filter(cls.group_name.ilike(group_name))

        else:

            gr = cls.query()\

                .filter(cls.group_name == group_name)

        if cache:

            gr = gr.options(FromCache(

                            "sql_cache_short",

                            "get_group_%s" % _hash_key(group_name)

                            )

            )

        return gr.scalar()

    @property

    def parents(self):

        parents_recursion_limit = 10

        groups = []

        if self.parent_group is None:

            return groups

        cur_gr = self.parent_group

        groups.insert(0, cur_gr)

        cnt = 0

        while 1:

            cnt += 1

            gr = getattr(cur_gr, 'parent_group', None)

            cur_gr = cur_gr.parent_group

            if gr is None:

                break

            if cnt == parents_recursion_limit:

                # this will prevent accidental infinite loops

                log.error(('more than %s parents found for group %s, stopping '

                           'recursive parent fetching' % (parents_recursion_limit, self)))

                break

            groups.insert(0, gr)

        return groups

    @property

    def children(self):

        return RepoGroup.query().filter(RepoGroup.parent_group == self)

    @property

    def name(self):

        return self.group_name.split(RepoGroup.url_sep())[-1]

    @property

    def full_path(self):

        return self.group_name

    @property

    def full_path_splitted(self):

        return self.group_name.split(RepoGroup.url_sep())

    @property

    def repositories(self):

        return Repository.query()\

                .filter(Repository.group == self)\

                .order_by(Repository.repo_name)

    @property

    def repositories_recursive_count(self):

        cnt = self.repositories.count()

        def children_count(group):

            cnt = 0

            for child in group.children:

                cnt += child.repositories.count()

                cnt += children_count(child)

            return cnt

        return cnt + children_count(self)

    def _recursive_objects(self, include_repos=True):

        all_ = []

        def _get_members(root_gr):

            if include_repos:

                for r in root_gr.repositories:

                    all_.append(r)

            childs = root_gr.children.all()

            if childs:

                for gr in childs:

                    all_.append(gr)

                    _get_members(gr)

        _get_members(self)

        return [self] + all_

    def recursive_groups_and_repos(self):

        """

        Recursive return all groups, with repositories in those groups

        """

        return self._recursive_objects()

    def recursive_groups(self):

        """

        Returns all children groups for this group including children of children

        """

        return self._recursive_objects(include_repos=False)

    def get_new_name(self, group_name):

        """

        returns new full group name based on parent and new name

        :param group_name:

        """

        path_prefix = (self.parent_group.full_path_splitted if

                       self.parent_group else [])

        return RepoGroup.url_sep().join(path_prefix + [group_name])

    def get_api_data(self):

        """

        Common function for generating api data

        """

        group = self

        data = dict(

            group_id=group.group_id,

            group_name=group.group_name,

            group_description=group.group_description,

            parent_group=group.parent_group.group_name if group.parent_group else None,

            repositories=[x.repo_name for x in group.repositories],

            owner=group.user.username

        )

        return data

class Permission(Base, BaseModel):

    __tablename__ = 'permissions'

    __table_args__ = (

        Index('p_perm_name_idx', 'permission_name'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True},

    )

    PERMS = [

        ('hg.admin', _('Kallithea Administrator')),

        ('repository.none', _('Default user has no access to new repositories')),

        ('repository.read', _('Default user has read access to new repositories')),

        ('repository.write', _('Default user has write access to new repositories')),

        ('repository.admin', _('Default user has admin access to new repositories')),

        ('group.none', _('Default user has no access to new repository groups')),

        'repository.read',

        'group.read',

        'usergroup.read',

        'hg.create.repository',

        'hg.create.write_on_repogroup.true',

        'hg.fork.repository',

        'hg.register.manual_activate',

        'hg.extern_activate.auto',

    ]

    # defines which permissions are more important higher the more important

    # Weight defines which permissions are more important.

    # The higher number the more important.

    PERM_WEIGHTS = {

        'repository.none': 0,

        'repository.read': 1,

        'repository.write': 3,

        'repository.admin': 4,

        'group.none': 0,

        'group.read': 1,

        'group.write': 3,

        'group.admin': 4,

        'usergroup.none': 0,

        'usergroup.read': 1,

        'usergroup.write': 3,

        'usergroup.admin': 4,

        'hg.repogroup.create.false': 0,

        'hg.repogroup.create.true': 1,

        'hg.usergroup.create.false': 0,

        'hg.usergroup.create.true': 1,

        'hg.fork.none': 0,

        'hg.fork.repository': 1,

        'hg.create.none': 0,

        'hg.create.repository': 1

    }

    permission_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    permission_name = Column(String(255, convert_unicode=False), nullable=True, unique=None, default=None)

    permission_longname = Column(String(255, convert_unicode=False), nullable=True, unique=None, default=None)

    def __unicode__(self):

        return u"<%s('%s:%s')>" % (

            self.__class__.__name__, self.permission_id, self.permission_name

        )

    @classmethod

    def get_by_key(cls, key):

        return cls.query().filter(cls.permission_name == key).scalar()

    @classmethod

    def get_default_perms(cls, default_user_id):

        q = Session().query(UserRepoToPerm, Repository, cls)\

         .join((Repository, UserRepoToPerm.repository_id == Repository.repo_id))\

         .join((cls, UserRepoToPerm.permission_id == cls.permission_id))\

         .filter(UserRepoToPerm.user_id == default_user_id)

        return q.all()

    @classmethod

    def get_default_group_perms(cls, default_user_id):

        q = Session().query(UserRepoGroupToPerm, RepoGroup, cls)\

         .join((RepoGroup, UserRepoGroupToPerm.group_id == RepoGroup.group_id))\

         .join((cls, UserRepoGroupToPerm.permission_id == cls.permission_id))\

         .filter(UserRepoGroupToPerm.user_id == default_user_id)

        return q.all()

    @classmethod

    def get_default_user_group_perms(cls, default_user_id):

        q = Session().query(UserUserGroupToPerm, UserGroup, cls)\

         .join((UserGroup, UserUserGroupToPerm.user_group_id == UserGroup.users_group_id))\

         .join((cls, UserUserGroupToPerm.permission_id == cls.permission_id))\

         .filter(UserUserGroupToPerm.user_id == default_user_id)

        return q.all()

class UserRepoToPerm(Base, BaseModel):

    __tablename__ = 'repo_to_perm'

    __table_args__ = (

        UniqueConstraint('user_id', 'repository_id', 'permission_id'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    repo_to_perm_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    user_id = Column(Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)

    permission_id = Column(Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)

    repository_id = Column(Integer(), ForeignKey('repositories.repo_id'), nullable=False, unique=None, default=None)

    user = relationship('User')

    repository = relationship('Repository')

    permission = relationship('Permission')

    @classmethod

    def create(cls, user, repository, permission):

        n = cls()

        n.user = user

        n.repository = repository

        n.permission = permission

        Session().add(n)

        return n

    def __unicode__(self):

        return u'<%s => %s >' % (self.user, self.repository)

class UserUserGroupToPerm(Base, BaseModel):

    __tablename__ = 'user_user_group_to_perm'

    __table_args__ = (

        UniqueConstraint('user_id', 'user_group_id', 'permission_id'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    user_user_group_to_perm_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    user_id = Column(Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)

    permission_id = Column(Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)

    user_group_id = Column(Integer(), ForeignKey('users_groups.users_group_id'), nullable=False, unique=None, default=None)

    user = relationship('User')

    user_group = relationship('UserGroup')

    permission = relationship('Permission')

    @classmethod

    def create(cls, user, user_group, permission):

        n = cls()

        n.user = user

        n.user_group = user_group

        n.permission = permission

        Session().add(n)

        return n

    def __unicode__(self):

        return u'<%s => %s >' % (self.user, self.user_group)

class UserToPerm(Base, BaseModel):

    __tablename__ = 'user_to_perm'

    __table_args__ = (

        UniqueConstraint('user_id', 'permission_id'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    user_to_perm_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    user_id = Column(Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)

    permission_id = Column(Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)

    user = relationship('User')

    permission = relationship('Permission')

    def __unicode__(self):

        return u'<%s => %s >' % (self.user, self.permission)

class UserGroupRepoToPerm(Base, BaseModel):

    __tablename__ = 'users_group_repo_to_perm'

    __table_args__ = (

        UniqueConstraint('repository_id', 'users_group_id', 'permission_id'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    users_group_to_perm_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    users_group_id = Column(Integer(), ForeignKey('users_groups.users_group_id'), nullable=False, unique=None, default=None)

    permission_id = Column(Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)

    repository_id = Column(Integer(), ForeignKey('repositories.repo_id'), nullable=False, unique=None, default=None)

    users_group = relationship('UserGroup')

    permission = relationship('Permission')

    repository = relationship('Repository')

    @classmethod

    def create(cls, users_group, repository, permission):

        n = cls()

        n.users_group = users_group

        n.repository = repository

        n.permission = permission

        Session().add(n)

        return n

    def __unicode__(self):

        return u'<UserGroupRepoToPerm:%s => %s >' % (self.users_group, self.repository)

class UserGroupUserGroupToPerm(Base, BaseModel):

    __tablename__ = 'user_group_user_group_to_perm'

    __table_args__ = (

        UniqueConstraint('target_user_group_id', 'user_group_id', 'permission_id'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    user_group_user_group_to_perm_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    target_user_group_id = Column(Integer(), ForeignKey('users_groups.users_group_id'), nullable=False, unique=None, default=None)

    permission_id = Column(Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)

    user_group_id = Column(Integer(), ForeignKey('users_groups.users_group_id'), nullable=False, unique=None, default=None)

    target_user_group = relationship('UserGroup', primaryjoin='UserGroupUserGroupToPerm.target_user_group_id==UserGroup.users_group_id')

    user_group = relationship('UserGroup', primaryjoin='UserGroupUserGroupToPerm.user_group_id==UserGroup.users_group_id')

    permission = relationship('Permission')

    @classmethod

    def create(cls, target_user_group, user_group, permission):

        n = cls()

        n.target_user_group = target_user_group

        n.user_group = user_group

        n.permission = permission

        Session().add(n)

        return n

    def __unicode__(self):

        return u'<UserGroupUserGroup:%s => %s >' % (self.target_user_group, self.user_group)

class UserGroupToPerm(Base, BaseModel):

    __tablename__ = 'users_group_to_perm'

    __table_args__ = (

        UniqueConstraint('users_group_id', 'permission_id',),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    users_group_to_perm_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    users_group_id = Column(Integer(), ForeignKey('users_groups.users_group_id'), nullable=False, unique=None, default=None)

    permission_id = Column(Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)

    users_group = relationship('UserGroup')

    permission = relationship('Permission')

class UserRepoGroupToPerm(Base, BaseModel):

    __tablename__ = 'user_repo_group_to_perm'

    __table_args__ = (

        UniqueConstraint('user_id', 'group_id', 'permission_id'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    group_to_perm_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    user_id = Column(Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)

    group_id = Column(Integer(), ForeignKey('groups.group_id'), nullable=False, unique=None, default=None)

    permission_id = Column(Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)

    user = relationship('User')

    group = relationship('RepoGroup')

    permission = relationship('Permission')

    @classmethod

    def create(cls, user, repository_group, permission):

        n = cls()

        n.user = user

        n.group = repository_group

        n.permission = permission

        Session().add(n)

        return n

class UserGroupRepoGroupToPerm(Base, BaseModel):

    __tablename__ = 'users_group_repo_group_to_perm'

    __table_args__ = (

        UniqueConstraint('users_group_id', 'group_id'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    users_group_repo_group_to_perm_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    users_group_id = Column(Integer(), ForeignKey('users_groups.users_group_id'), nullable=False, unique=None, default=None)

    group_id = Column(Integer(), ForeignKey('groups.group_id'), nullable=False, unique=None, default=None)

    permission_id = Column(Integer(), ForeignKey('permissions.permission_id'), nullable=False, unique=None, default=None)

    users_group = relationship('UserGroup')

    permission = relationship('Permission')

    group = relationship('RepoGroup')

    @classmethod

    def create(cls, user_group, repository_group, permission):

        n = cls()

        n.users_group = user_group

        n.group = repository_group

        n.permission = permission

        Session().add(n)

        return n

class Statistics(Base, BaseModel):

    __tablename__ = 'statistics'

    __table_args__ = (

         UniqueConstraint('repository_id'),

         {'extend_existing': True, 'mysql_engine': 'InnoDB',

          'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    stat_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    repository_id = Column(Integer(), ForeignKey('repositories.repo_id'), nullable=False, unique=True, default=None)

    stat_on_revision = Column(Integer(), nullable=False)

    commit_activity = Column(LargeBinary(1000000), nullable=False)#JSON data

    commit_activity_combined = Column(LargeBinary(), nullable=False)#JSON data

    languages = Column(LargeBinary(1000000), nullable=False)#JSON data

    repository = relationship('Repository', single_parent=True)

class UserFollowing(Base, BaseModel):

    __tablename__ = 'user_followings'

    __table_args__ = (

        UniqueConstraint('user_id', 'follows_repository_id'),

        UniqueConstraint('user_id', 'follows_user_id'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True}

    )

    user_following_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    user_id = Column(Integer(), ForeignKey('users.user_id'), nullable=False, unique=None, default=None)

    follows_repo_id = Column("follows_repository_id", Integer(), ForeignKey('repositories.repo_id'), nullable=True, unique=None, default=None)

    follows_user_id = Column(Integer(), ForeignKey('users.user_id'), nullable=True, unique=None, default=None)

    follows_from = Column(DateTime(timezone=False), nullable=True, unique=None, default=datetime.datetime.now)

    user = relationship('User', primaryjoin='User.user_id==UserFollowing.user_id')

    follows_user = relationship('User', primaryjoin='User.user_id==UserFollowing.follows_user_id')

    follows_repository = relationship('Repository', order_by='Repository.repo_name')

    @classmethod

    def get_repo_followers(cls, repo_id):

        return cls.query().filter(cls.follows_repo_id == repo_id)

class CacheInvalidation(Base, BaseModel):

    __tablename__ = 'cache_invalidation'

    __table_args__ = (

        UniqueConstraint('cache_key'),

        Index('key_idx', 'cache_key'),

        {'extend_existing': True, 'mysql_engine': 'InnoDB',

         'mysql_charset': 'utf8', 'sqlite_autoincrement': True},

    )

    # cache_id, not used

    cache_id = Column(Integer(), nullable=False, unique=True, primary_key=True)

    # cache_key as created by _get_cache_key

    cache_key = Column(String(255, convert_unicode=False))

    # cache_args is a repo_name

    cache_args = Column(String(255, convert_unicode=False))

    # instance sets cache_active True when it is caching, other instances set

    # cache_active to False to indicate that this cache is invalid

    cache_active = Column(Boolean(), nullable=True, unique=None, default=False)

    def __init__(self, cache_key, repo_name=''):

        self.cache_key = cache_key

        self.cache_args = repo_name

        self.cache_active = False

    def __unicode__(self):

        return u"<%s('%s:%s[%s]')>" % (

            self.__class__.__name__,

            self.cache_id, self.cache_key, self.cache_active)

    def _cache_key_partition(self):

        prefix, repo_name, suffix = self.cache_key.partition(self.cache_args)

        return prefix, repo_name, suffix

    def get_prefix(self):

        """

        get prefix that might have been used in _get_cache_key to

        generate self.cache_key. Only used for informational purposes

        in repo_edit.html.

        """

        # prefix, repo_name, suffix

        return self._cache_key_partition()[0]

    def get_suffix(self):

        """

        get suffix that might have been used in _get_cache_key to

        generate self.cache_key. Only used for informational purposes

        in repo_edit.html.

        """

        # prefix, repo_name, suffix

        return self._cache_key_partition()[2]

    @classmethod

    def clear_cache(cls):

        """

        Delete all cache keys from database.

        Should only be run when all instances are down and all entries thus stale.

        """