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

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

    permission_id = Column("permission_id", 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("users_group_repo_group_to_perm_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)

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

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

    permission_id = Column("permission_id", 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("stat_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)

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

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

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

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

    languages = Column("languages", 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("user_following_id", Integer(), nullable=False, unique=True, default=None, primary_key=True)

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

    follows_from = Column('follows_from', 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_key as created by _get_cache_key

    # cache_args is a repo_name

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

        self.cache_key = cache_key

        self.cache_args = repo_name

        self.cache_active = False

    def __unicode__(self):

    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.

        """

        cls.query().delete()

        Session().commit()

    @classmethod

    def _get_cache_key(cls, key):

        """

        Wrapper for generating a unique cache key for this instance and "key".

        key must / will start with a repo_name which will be stored in .cache_args .

        """

        import kallithea

        prefix = kallithea.CONFIG.get('instance_id', '')

        return "%s%s" % (prefix, key)

    @classmethod

    def set_invalidate(cls, repo_name, delete=False):

        """

        Mark all caches of a repo as invalid in the database.

        """

        inv_objs = Session().query(cls).filter(cls.cache_args == repo_name).all()

        log.debug('for repo %s got %s invalidation objects'

                  % (safe_str(repo_name), inv_objs))

        for inv_obj in inv_objs:

            log.debug('marking %s key for invalidation based on repo_name=%s'

                      % (inv_obj, safe_str(repo_name)))

            if delete:

                Session().delete(inv_obj)

            else:

                inv_obj.cache_active = False

                Session().add(inv_obj)

        Session().commit()

    @classmethod

    def test_and_set_valid(cls, repo_name, kind, valid_cache_keys=None):

        """

        Mark this cache key as active and currently cached.

        Return True if the existing cache registration still was valid.

        Return False to indicate that it had been invalidated and caches should be refreshed.

        """

        key = (repo_name + '_' + kind) if kind else repo_name

        cache_key = cls._get_cache_key(key)

        if valid_cache_keys and cache_key in valid_cache_keys:

            return True

        inv_obj = cls.query().filter(cls.cache_key == cache_key).scalar()

        if not inv_obj:

            inv_obj = CacheInvalidation(cache_key, repo_name)

        if inv_obj.cache_active:

            return True

        inv_obj.cache_active = True

        Session().add(inv_obj)

        Session().commit()

        return False

    @classmethod

    def get_valid_cache_keys(cls):

        """

        Return opaque object with information of which caches still are valid

        and can be used without checking for invalidation.

        """

        return set(inv_obj.cache_key for inv_obj in cls.query().filter(cls.cache_active).all())

class ChangesetComment(Base, BaseModel):

    __tablename__ = 'changeset_comments'