class AuthUser(object):

    """

    Represents a Kallithea user, including various authentication and

    authorization information. Typically used to store the current user,

    but is also used as a generic user information data structure in

    parts of the code, e.g. user management.

    Constructed from a database `User` object, a user ID or cookie dict,

    it looks up the user (if needed) and copies all attributes to itself,

    adding various non-persistent data. If lookup fails but anonymous

    access to Kallithea is enabled, the default user is loaded instead.

    However, `AuthUser` does refuse to load a user that is not `active`.

    Note that Kallithea distinguishes between the default user (an actual

    user in the database with username "default") and "no user" (no actual

    User object, AuthUser filled with blank values and username "None").

    If the default user is active, that will always be used instead of

    "no user". On the other hand, if the default user is disabled (and

    there is no login information), we instead get "no user"; this should

    only happen on the login page (as all other requests are redirected).

    `is_default_user` specifically checks if the AuthUser is the user named

    "default". Use `is_anonymous` to check for both "default" and "no user".

    """

    def __init__(self, user_id=None, dbuser=None, authenticating_api_key=None,

            is_external_auth=False):

        self.is_external_auth = is_external_auth

        self.authenticating_api_key = authenticating_api_key

        # These attributes will be overridden by fill_data, below, unless the

        # requested user cannot be found and the default anonymous user is

        # not enabled.

        self.user_id = None

        self.username = None

        self.api_key = None

        self.name = ''

        self.lastname = ''

        self.email = ''

        user (an `AuthUser` or `db.User`).

        """

        allowed_ips = AuthUser.get_allowed_ips(user.user_id, cache=True)

        if check_ip_access(source_ip=ip_addr, allowed_ips=allowed_ips):

            log.debug('IP:%s is in range of %s', ip_addr, allowed_ips)

            return True

        else:

            log.info('Access for IP:%s forbidden, '

                     'not in %s' % (ip_addr, allowed_ips))

            return False

    def __repr__(self):

    def to_cookie(self):

        """ Serializes this login session to a cookie `dict`. """

        return {

            'user_id': self.user_id,

            'is_external_auth': self.is_external_auth,

        }

    @staticmethod

    def from_cookie(cookie):

        """

        Deserializes an `AuthUser` from a cookie `dict`.

        """

        au = AuthUser(

            user_id=cookie.get('user_id'),

            is_external_auth=cookie.get('is_external_auth', False),

        )

        return au

    @classmethod

    def get_allowed_ips(cls, user_id, cache=False):

        _set = set()

        default_ips = UserIpMap.query().filter(UserIpMap.user_id ==

                                        User.get_default_user(cache=True).user_id)

        if cache:

            default_ips = default_ips.options(FromCache("sql_cache_short",

                                              "get_user_ips_default"))

        for ip in default_ips:

    the session cookie is set to expire in a year; otherwise, it expires at

    the end of the browser session.

    Returns populated `AuthUser` object.

    """

    user.update_lastlogin()

    meta.Session().commit()

    auth_user = AuthUser(dbuser=user,

                         is_external_auth=is_external_auth)

    # It should not be possible to explicitly log in as the default user.

    assert not auth_user.is_default_user

    # Start new session to prevent session fixation attacks.

    session.invalidate()

    session['authuser'] = cookie = auth_user.to_cookie()

    # If they want to be remembered, update the cookie.

    # NOTE: Assumes that beaker defaults to browser session cookie.

    if remember:

        t = datetime.datetime.now() + datetime.timedelta(days=365)

        session._set_cookie_expires(t)

    session.save()