evennia/evennia/server/session.py

"""
This module defines a generic session class. All connection instances
(both on Portal and Server side) should inherit from this class.

"""
from django.conf import settings

import time

# ------------------------------------------------------------
# Server Session
# ------------------------------------------------------------


class Session:
    """
    This class represents a player's session and is a template for
    both portal- and server-side sessions.

    Each connection will see two session instances created:

     1. A Portal session. This is customized for the respective connection
        protocols that Evennia supports, like Telnet, SSH etc. The Portal
        session must call init_session() as part of its initialization. The
        respective hook methods should be connected to the methods unique
        for the respective protocol so that there is a unified interface
        to Evennia.
     2. A Server session. This is the same for all connected accounts,
        regardless of how they connect.

    The Portal and Server have their own respective sessionhandlers. These
    are synced whenever new connections happen or the Server restarts etc,
    which means much of the same information must be stored in both places
    e.g. the portal can re-sync with the server when the server reboots.

    """

    def init_session(self, protocol_key, address, sessionhandler):
        """
        Initialize the Session. This should be called by the protocol when
        a new session is established.

        Args:
            protocol_key (str): By default, one of 'telnet', 'telnet/ssl', 'ssh',
                'webclient/websocket' or 'webclient/ajax'.
            address (str): Client address.
            sessionhandler (SessionHandler): Reference to the
                main sessionhandler instance.

        """
        # This is currently 'telnet', 'ssh', 'ssl' or 'web'
        self.protocol_key = protocol_key
        # Protocol address tied to this session
        self.address = address

        # suid is used by some protocols, it's a hex key.
        self.suid = None

        # unique id for this session
        self.sessid = 0  # no sessid yet
        # client session id, if given by the client
        self.csessid = None
        # database id for the user connected to this session
        self.uid = None
        # user name, for easier tracking of sessions
        self.uname = None
        # if user has authenticated already or not
        self.logged_in = False

        # database id of puppeted object (if any)
        self.puid = None

        # session time statistics
        self.conn_time = time.time()
        self.cmd_last_visible = self.conn_time
        self.cmd_last = self.conn_time
        self.cmd_total = 0

        self.protocol_flags = {
            "ENCODING": "utf-8",
            "SCREENREADER": False,
            "INPUTDEBUG": False,
            "RAW": False,
            "NOCOLOR": False,
            "LOCALECHO": False,
        }
        self.server_data = {}

        # map of input data to session methods
        self.datamap = {}

        # a back-reference to the relevant sessionhandler this
        # session is stored in.
        self.sessionhandler = sessionhandler

    def get_sync_data(self):
        """
        Get all data relevant to sync the session.

        Args:
            syncdata (dict): All syncdata values, based on
                the keys given by self._attrs_to_sync.

        """
        return {
            attr: getattr(self, attr) for attr in settings.SESSION_SYNC_ATTRS if hasattr(self, attr)
        }

    def load_sync_data(self, sessdata):
        """
        Takes a session dictionary, as created by get_sync_data, and
        loads it into the correct properties of the session.

        Args:
            sessdata (dict): Session data dictionary.

        """
        for propname, value in sessdata.items():
            if (
                propname == "protocol_flags"
                and isinstance(value, dict)
                and hasattr(self, "protocol_flags")
                and isinstance(self.protocol_flags, dict)
            ):
                # special handling to allow partial update of protocol flags
                self.protocol_flags.update(value)
            else:
                setattr(self, propname, value)

    def at_sync(self):
        """
        Called after a session has been fully synced (including
        secondary operations such as setting self.account based
        on uid etc).

        """
        if self.account:
            self.protocol_flags.update(
                self.account.attributes.get("_saved_protocol_flags", None) or {}
            )

    # access hooks

    def disconnect(self, reason=None):
        """
        generic hook called from the outside to disconnect this session
        should be connected to the protocols actual disconnect mechanism.

        Args:
            reason (str): Eventual text motivating the disconnect.

        """
        pass

    def data_out(self, **kwargs):
        """
        Generic hook for sending data out through the protocol. Server
        protocols can use this right away. Portal sessions
        should overload this to format/handle the outgoing data as needed.

        Keyword Args:
            kwargs (any): Other data to the protocol.

        """
        pass

    def data_in(self, **kwargs):
        """
        Hook for protocols to send incoming data to the engine.

        Keyword Args:
            kwargs (any): Other data from the protocol.

        """
        pass