twblue/src/sessions/base.py

# -*- coding: utf-8 -*-
""" A base class to be derived in possible new sessions for TWBlue and services."""
from __future__ import absolute_import
from __future__ import unicode_literals
from builtins import str
from builtins import object
import os
import paths
import output
import time
import sound
import logging
import config_utils
import sqlitedict
import application
import os
from . import session_exceptions as Exceptions
log = logging.getLogger("sessionmanager.session")


class baseSession(object):
    """ toDo: Decorators does not seem to be working when using them in an inherited class."""

    # Decorators.

    def _require_login(fn):
        """ Decorator for checking if the user is logged in.
        Some functions may need this to avoid making unneeded calls."""
        def f(self, *args, **kwargs):
            if self.logged == True:
                fn(self, *args, **kwargs)
            else:
                raise Exceptions.NotLoggedSessionError("You are not logged in yet.")
        return f

    def _require_configuration(fn):
        """ Check if the user has a configured session."""
        def f(self, *args, **kwargs):
            if self.settings != None:
                fn(self, *args, **kwargs)
            else:
                raise Exceptions.NotConfiguredSessionError("Not configured.")
        return f

    def __init__(self, session_id):
        """ session_id (str): The name of the folder inside the config directory where the session is located."""
        super(baseSession, self).__init__()
        self.session_id = session_id
        self.logged = False
        self.settings = None
        self.db={}

    @property
    def is_logged(self):
        return self.logged

    def get_configuration(self):
        """ Get settings for a session."""
        file_ = "%s/session.conf" % (self.session_id,)
        log.debug("Creating config file %s" % (file_,))
        self.settings = config_utils.load_config(os.path.join(paths.config_path(), file_), os.path.join(paths.app_path(), "Conf.defaults"))
        self.init_sound()
        self.deshelve()

    def init_sound(self):
        try: self.sound = sound.soundSystem(self.settings["sound"])
        except: pass

    @_require_configuration
    def login(self, verify_credentials=True):
        pass

    @_require_configuration
    def authorise(self):
        pass

    def shelve(self):
        """Shelve the database to allow for persistance."""
        shelfname=os.path.join(paths.config_path(), str(self.session_id), "cache")
        if self.settings["general"]["persist_size"] == 0:
            if os.path.exists(shelfname+".dat"):
                os.remove(shelfname+".dat")
            return
        try:
            self.db.commit()
#            if not os.path.exists(shelfname+".dat"):
#                output.speak("Generating database, this might take a while.",True)
#            shelf=shelve.open(os.path.join(paths.config_path(), shelfname),'c')
#            for key, value in list(self.db.items()):
#                if type(key) != str and type(key) != str:
#                    output.speak("Uh oh, while shelving the database, a key of type " + str(type(key)) + " has been found. It will be converted to type str, but this will cause all sorts of problems on deshelve. Please bring this to the attention of the " + application.name + " developers immediately. More information about the error will be written to the error log.",True)
#                    log.error("Uh oh, " + str(key) + " is of type " + str(type(key)) + "!")
#                if type(value) == list and self.settings["general"]["persist_size"] != -1 and len(value) > self.settings["general"]["persist_size"]:
#                    shelf[key]=value[self.settings["general"]["persist_size"]:]
#                else:
#                    shelf[key]=value
#            shelf.close()
        except:
            output.speak("An exception occurred while shelving the " + application.name + " database. It will be deleted and rebuilt automatically. If this error persists, send the error log to the " + application.name + " developers.",True)
            log.exception("Exception while shelving" + shelfname)
            os.remove(shelfname)

    def deshelve(self):
        """Import a shelved database."""
        shelfname=os.path.join(paths.config_path(), str(self.session_id)+"/cache")
        if self.settings["general"]["persist_size"] == 0:
            if os.path.exists(shelfname+".dat"):
                os.remove(shelfname+".dat")
            return
        try:
            self.db=sqlitedict.SqliteDict(os.path.join(paths.config_path(), shelfname), 'c')
            if self.db.get("cursors") == None:
                cursors = dict(direct_messages=-1)
                self.db["cursors"] = cursors
#            for key,value in list(shelf.items()):
#                self.db[key]=value
#            shelf.close()
        except:
            output.speak("An exception occurred while deshelving the " + application.name + " database. It will be deleted and rebuilt automatically. If this error persists, send the error log to the " + application.name + " developers.",True)
            log.exception("Exception while deshelving" + shelfname)
            try: 
                os.remove(shelfname)
            except:
                pass