plexpy/plexpy/__init__.py

# This file is part of PlexPy.
#
#  PlexPy is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  PlexPy is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with PlexPy.  If not, see <http://www.gnu.org/licenses/>.

import os
import sys
import subprocess
import threading
import sqlite3
import cherrypy
import datetime
import uuid
# Some cut down versions of Python may not include this module and it's not critical for us
try:
    import webbrowser
    no_browser = False
except ImportError:
    no_browser = True

from apscheduler.schedulers.background import BackgroundScheduler
from apscheduler.triggers.interval import IntervalTrigger

from plexpy import versioncheck, logger, activity_pinger, plextv, pmsconnect
import plexpy.config

PROG_DIR = None
FULL_PATH = None

ARGS = None
SIGNAL = None

SYS_PLATFORM = None
SYS_ENCODING = None

QUIET = False
VERBOSE = True
DAEMON = False
CREATEPID = False
PIDFILE = None

SCHED = BackgroundScheduler()
SCHED_LOCK = threading.Lock()

INIT_LOCK = threading.Lock()
_INITIALIZED = False
started = False

DATA_DIR = None

CONFIG = None

DB_FILE = None

LOG_LIST = []

INSTALL_TYPE = None
CURRENT_VERSION = None
LATEST_VERSION = None
COMMITS_BEHIND = None

UMASK = None

POLLING_FAILOVER = False

def initialize(config_file):
    with INIT_LOCK:

        global CONFIG
        global _INITIALIZED
        global CURRENT_VERSION
        global LATEST_VERSION
        global UMASK
        global POLLING_FAILOVER

        CONFIG = plexpy.config.Config(config_file)

        assert CONFIG is not None

        if _INITIALIZED:
            return False

        if CONFIG.HTTP_PORT < 21 or CONFIG.HTTP_PORT > 65535:
            plexpy.logger.warn(
                'HTTP_PORT out of bounds: 21 < %s < 65535', CONFIG.HTTP_PORT)
            CONFIG.HTTP_PORT = 8181

        if CONFIG.HTTPS_CERT == '':
            CONFIG.HTTPS_CERT = os.path.join(DATA_DIR, 'server.crt')
        if CONFIG.HTTPS_KEY == '':
            CONFIG.HTTPS_KEY = os.path.join(DATA_DIR, 'server.key')

        if not CONFIG.LOG_DIR:
            CONFIG.LOG_DIR = os.path.join(DATA_DIR, 'logs')

        if not os.path.exists(CONFIG.LOG_DIR):
            try:
                os.makedirs(CONFIG.LOG_DIR)
            except OSError:
                CONFIG.LOG_DIR = None

                if not QUIET:
                    sys.stderr.write("Unable to create the log directory. " \
                                     "Logging to screen only.\n")

        # Start the logger, disable console if needed
        logger.initLogger(console=not QUIET, log_dir=CONFIG.LOG_DIR,
                          verbose=VERBOSE)

        if not CONFIG.CACHE_DIR:
            # Put the cache dir in the data dir for now
            CONFIG.CACHE_DIR = os.path.join(DATA_DIR, 'cache')
        if not os.path.exists(CONFIG.CACHE_DIR):
            try:
                os.makedirs(CONFIG.CACHE_DIR)
            except OSError as e:
                logger.error("Could not create cache dir '%s': %s", DATA_DIR, e)

        # Initialize the database
        logger.info('Checking to see if the database has all tables....')
        try:
            dbcheck()
        except Exception as e:
            logger.error("Can't connect to the database: %s", e)

        # Check if PlexPy has a uuid
        if CONFIG.PMS_UUID == '' or not CONFIG.PMS_UUID:
            my_uuid = generate_uuid()
            CONFIG.__setattr__('PMS_UUID', my_uuid)
            CONFIG.write()

        # Get the currently installed version. Returns None, 'win32' or the git
        # hash.
        CURRENT_VERSION, CONFIG.GIT_BRANCH = versioncheck.getVersion()

        # Write current version to a file, so we know which version did work.
        # This allowes one to restore to that version. The idea is that if we
        # arrive here, most parts of PlexPy seem to work.
        if CURRENT_VERSION:
            version_lock_file = os.path.join(DATA_DIR, "version.lock")

            try:
                with open(version_lock_file, "w") as fp:
                    fp.write(CURRENT_VERSION)
            except IOError as e:
                logger.error("Unable to write current version to file '%s': %s",
                             version_lock_file, e)

        # Check for new versions
        if CONFIG.CHECK_GITHUB_ON_STARTUP and CONFIG.CHECK_GITHUB:
            try:
                LATEST_VERSION = versioncheck.checkGithub()
            except:
                logger.exception("Unhandled exception")
                LATEST_VERSION = CURRENT_VERSION
        else:
            LATEST_VERSION = CURRENT_VERSION

        # Get the real PMS urls for SSL and remote access
        if CONFIG.PMS_TOKEN and CONFIG.PMS_IP and CONFIG.PMS_PORT:
            plextv.get_real_pms_url()
            pmsconnect.get_server_friendly_name()

        # Refresh the users list on startup
        if CONFIG.PMS_TOKEN and CONFIG.REFRESH_USERS_ON_STARTUP:
            plextv.refresh_users()

        # Store the original umask
        UMASK = os.umask(0)
        os.umask(UMASK)

        _INITIALIZED = True
        return True


def daemonize():
    if threading.activeCount() != 1:
        logger.warn(
            'There are %r active threads. Daemonizing may cause'
            ' strange behavior.',
            threading.enumerate())

    sys.stdout.flush()
    sys.stderr.flush()

    # Do first fork
    try:
        pid = os.fork()  # @UndefinedVariable - only available in UNIX
        if pid != 0:
            sys.exit(0)
    except OSError, e:
        raise RuntimeError("1st fork failed: %s [%d]", e.strerror, e.errno)

    os.setsid()

    # Make sure I can read my own files and shut out others
    prev = os.umask(0)  # @UndefinedVariable - only available in UNIX
    os.umask(prev and int('077', 8))

    # Make the child a session-leader by detaching from the terminal
    try:
        pid = os.fork()  # @UndefinedVariable - only available in UNIX
        if pid != 0:
            sys.exit(0)
    except OSError, e:
        raise RuntimeError("2nd fork failed: %s [%d]", e.strerror, e.errno)

    dev_null = file('/dev/null', 'r')
    os.dup2(dev_null.fileno(), sys.stdin.fileno())

    si = open('/dev/null', "r")
    so = open('/dev/null', "a+")
    se = open('/dev/null', "a+")

    os.dup2(si.fileno(), sys.stdin.fileno())
    os.dup2(so.fileno(), sys.stdout.fileno())
    os.dup2(se.fileno(), sys.stderr.fileno())

    pid = os.getpid()
    logger.info('Daemonized to PID: %d', pid)

    if CREATEPID:
        logger.info("Writing PID %d to %s", pid, PIDFILE)
        with file(PIDFILE, 'w') as fp:
            fp.write("%s\n" % pid)


def launch_browser(host, port, root):
    if not no_browser:
        if host == '0.0.0.0':
            host = 'localhost'

        if CONFIG.ENABLE_HTTPS:
            protocol = 'https'
        else:
            protocol = 'http'

        try:
            webbrowser.open('%s://%s:%i%s' % (protocol, host, port, root))
        except Exception as e:
            logger.error('Could not launch browser: %s', e)


def initialize_scheduler():
    """
    Start the scheduled background tasks. Re-schedule if interval settings changed.
    """



    with SCHED_LOCK:

        # Check if scheduler should be started
        start_jobs = not len(SCHED.get_jobs())

        # Update check
        if CONFIG.CHECK_GITHUB_INTERVAL and CONFIG.CHECK_GITHUB:
            minutes = CONFIG.CHECK_GITHUB_INTERVAL
        else:
            minutes = 0
        schedule_job(versioncheck.checkGithub, 'Check GitHub for updates', hours=0, minutes=minutes)

        # Start checking for new sessions at set interval
        if CONFIG.MONITORING_INTERVAL:
            # Our interval should never be less than 30 seconds
            if CONFIG.MONITORING_INTERVAL > 30:
                seconds = CONFIG.MONITORING_INTERVAL
            else:
                seconds = 30
        else:
            seconds = 0

        if CONFIG.PMS_IP and CONFIG.PMS_TOKEN:
            schedule_job(plextv.get_real_pms_url, 'Refresh Plex Server URLs',
                         hours=12, minutes=0, seconds=0)
            schedule_job(pmsconnect.get_server_friendly_name, 'Refresh Plex Server Name',
                         hours=12, minutes=0, seconds=0)
            schedule_job(activity_pinger.check_recently_added, 'Check for recently added items',
                         hours=0, minutes=0, seconds=seconds)
            schedule_job(activity_pinger.check_server_response, 'Check for server response',
                         hours=0, minutes=0, seconds=seconds)

            # If we're not using websockets then fall back to polling
            if not CONFIG.MONITORING_USE_WEBSOCKET or POLLING_FAILOVER:
                schedule_job(activity_pinger.check_active_sessions, 'Check for active sessions',
                             hours=0, minutes=0, seconds=seconds)

        # Refresh the users list
        if CONFIG.REFRESH_USERS_INTERVAL:
            hours = CONFIG.REFRESH_USERS_INTERVAL
        else:
            hours = 0

        if CONFIG.PMS_TOKEN:
            schedule_job(plextv.refresh_users, 'Refresh users list', hours=hours, minutes=0, seconds=0)

        # Start scheduler
        if start_jobs and len(SCHED.get_jobs()):
            try:
                SCHED.start()
            except Exception as e:
                logger.info(e)

                # Debug
                #SCHED.print_jobs()


def schedule_job(function, name, hours=0, minutes=0, seconds=0):
    """
    Start scheduled job if starting or restarting plexpy.
    Reschedule job if Interval Settings have changed.
    Remove job if if Interval Settings changed to 0

    """

    job = SCHED.get_job(name)
    if job:
        if hours == 0 and minutes == 0 and seconds == 0:
            SCHED.remove_job(name)
            logger.info("Removed background task: %s", name)
        elif job.trigger.interval != datetime.timedelta(hours=hours, minutes=minutes):
            SCHED.reschedule_job(name, trigger=IntervalTrigger(
                hours=hours, minutes=minutes, seconds=seconds))
            logger.info("Re-scheduled background task: %s", name)
    elif hours > 0 or minutes > 0 or seconds > 0:
        SCHED.add_job(function, id=name, trigger=IntervalTrigger(
            hours=hours, minutes=minutes, seconds=seconds))
        logger.info("Scheduled background task: %s", name)


def start():
    global started

    if _INITIALIZED:
        initialize_scheduler()
        started = True


def sig_handler(signum=None, frame=None):
    if signum is not None:
        logger.info("Signal %i caught, saving and exiting...", signum)
        shutdown()


def dbcheck():
    conn_db = sqlite3.connect(DB_FILE)
    c_db = conn_db.cursor()

    # sessions table :: This is a temp table that logs currently active sessions
    c_db.execute(
        'CREATE TABLE IF NOT EXISTS sessions (id INTEGER PRIMARY KEY AUTOINCREMENT, '
        'session_key INTEGER, rating_key INTEGER, media_type TEXT, started INTEGER, '
        'paused_counter INTEGER DEFAULT 0, state TEXT, user_id INTEGER, user TEXT, friendly_name TEXT, '
        'ip_address TEXT, machine_id TEXT, player TEXT, platform TEXT, title TEXT, parent_title TEXT, '
        'grandparent_title TEXT, parent_rating_key INTEGER, grandparent_rating_key INTEGER, '
        'view_offset INTEGER DEFAULT 0, duration INTEGER, video_decision TEXT, audio_decision TEXT, '
        'width INTEGER, height INTEGER, container TEXT, video_codec TEXT, audio_codec TEXT, '
        'bitrate INTEGER, video_resolution TEXT, video_framerate TEXT, aspect_ratio TEXT, '
        'audio_channels INTEGER, transcode_protocol TEXT, transcode_container TEXT, '
        'transcode_video_codec TEXT, transcode_audio_codec TEXT, transcode_audio_channels INTEGER,'
        'transcode_width INTEGER, transcode_height INTEGER, buffer_count INTEGER DEFAULT 0, '
        'buffer_last_triggered INTEGER, last_paused INTEGER)'
    )

    # session_history table :: This is a history table which logs essential stream details
    c_db.execute(
        'CREATE TABLE IF NOT EXISTS session_history (id INTEGER PRIMARY KEY AUTOINCREMENT, reference_id INTEGER, '
        'started INTEGER, stopped INTEGER, rating_key INTEGER, user_id INTEGER, user TEXT, '
        'ip_address TEXT, paused_counter INTEGER DEFAULT 0, player TEXT, platform TEXT, machine_id TEXT, '
        'parent_rating_key INTEGER, grandparent_rating_key INTEGER, media_type TEXT, view_offset INTEGER DEFAULT 0)'
    )

    # session_history_media_info table :: This is a table which logs each session's media info
    c_db.execute(
        'CREATE TABLE IF NOT EXISTS session_history_media_info (id INTEGER PRIMARY KEY, '
        'rating_key INTEGER, video_decision TEXT, audio_decision TEXT, duration INTEGER DEFAULT 0, width INTEGER, '
        'height INTEGER, container TEXT, video_codec TEXT, audio_codec TEXT, bitrate INTEGER, video_resolution TEXT, '
        'video_framerate TEXT, aspect_ratio TEXT, audio_channels INTEGER, transcode_protocol TEXT, '
        'transcode_container TEXT, transcode_video_codec TEXT, transcode_audio_codec TEXT, '
        'transcode_audio_channels INTEGER, transcode_width INTEGER, transcode_height INTEGER)'
    )

    # session_history_metadata table :: This is a table which logs each session's media metadata
    c_db.execute(
        'CREATE TABLE IF NOT EXISTS session_history_metadata (id INTEGER PRIMARY KEY, '
        'rating_key INTEGER, parent_rating_key INTEGER, grandparent_rating_key INTEGER, '
        'title TEXT, parent_title TEXT, grandparent_title TEXT, full_title TEXT, media_index INTEGER, '
        'parent_media_index INTEGER, thumb TEXT, parent_thumb TEXT, grandparent_thumb TEXT, art TEXT, media_type TEXT, '
        'year INTEGER, originally_available_at TEXT, added_at INTEGER, updated_at INTEGER, last_viewed_at INTEGER, '
        'content_rating TEXT, summary TEXT, tagline TEXT, rating TEXT, duration INTEGER DEFAULT 0, guid TEXT, '
        'directors TEXT, writers TEXT, actors TEXT, genres TEXT, studio TEXT)'
        ''
    )

    # users table :: This table keeps record of the friends list
    c_db.execute(
        'CREATE TABLE IF NOT EXISTS users (id INTEGER PRIMARY KEY AUTOINCREMENT, '
        'user_id INTEGER DEFAULT NULL UNIQUE, username TEXT NOT NULL UNIQUE, '
        'friendly_name TEXT, thumb TEXT, email TEXT, custom_avatar_url TEXT, is_home_user INTEGER DEFAULT NULL, '
        'is_allow_sync INTEGER DEFAULT NULL, is_restricted INTEGER DEFAULT NULL, do_notify INTEGER DEFAULT 1, '
        'keep_history INTEGER DEFAULT 1, deleted_user INTEGER DEFAULT 0)'
    )

    # Upgrade sessions table from earlier versions
    try:
        c_db.execute('SELECT started from sessions')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table sessions.")
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN started INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN paused_counter INTEGER DEFAULT 0'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN state TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN user TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN machine_id TEXT'
        )

    # Upgrade sessions table from earlier versions
    try:
        c_db.execute('SELECT title from sessions')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table sessions.")
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN title TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN parent_title TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN grandparent_title TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN friendly_name TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN player TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN user_id INTEGER'
        )

    # Upgrade sessions table from earlier versions
    try:
        c_db.execute('SELECT ip_address from sessions')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table sessions.")
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN ip_address TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN platform TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN parent_rating_key INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN grandparent_rating_key INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN view_offset INTEGER DEFAULT 0'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN duration INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN video_decision TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN audio_decision TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN width INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN height INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN container TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN video_codec TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN audio_codec TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN bitrate INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN video_resolution TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN video_framerate TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN aspect_ratio TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN audio_channels INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN transcode_protocol TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN transcode_container TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN transcode_video_codec TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN transcode_audio_codec TEXT'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN transcode_audio_channels INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN transcode_width INTEGER'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN transcode_height INTEGER'
        )

    # Upgrade session_history_metadata table from earlier versions
    try:
        c_db.execute('SELECT full_title from session_history_metadata')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table session_history_metadata.")
        c_db.execute(
            'ALTER TABLE session_history_metadata ADD COLUMN full_title TEXT'
        )

    # Upgrade session_history_metadata table from earlier versions
    try:
        c_db.execute('SELECT tagline from session_history_metadata')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table session_history_metadata.")
        c_db.execute(
            'ALTER TABLE session_history_metadata ADD COLUMN tagline TEXT'
        )

    # notify_log table :: This is a table which logs notifications sent
    c_db.execute(
        'CREATE TABLE IF NOT EXISTS notify_log (id INTEGER PRIMARY KEY AUTOINCREMENT, '
        'session_key INTEGER, rating_key INTEGER, user_id INTEGER, user TEXT, '
        'agent_id INTEGER, agent_name TEXT, on_play INTEGER, on_stop INTEGER, on_watched INTEGER, '
        'on_pause INTEGER, on_resume INTEGER, on_buffer INTEGER, on_created INTEGER)'
    )

    # Upgrade users table from earlier versions
    try:
        c_db.execute('SELECT do_notify from users')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table users.")
        c_db.execute(
            'ALTER TABLE users ADD COLUMN do_notify INTEGER DEFAULT 1'
        )

    # Upgrade users table from earlier versions
    try:
        c_db.execute('SELECT keep_history from users')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table users.")
        c_db.execute(
            'ALTER TABLE users ADD COLUMN keep_history INTEGER DEFAULT 1'
        )

    # Upgrade notify_log table from earlier versions
    try:
        c_db.execute('SELECT on_pause from notify_log')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table notify_log.")
        c_db.execute(
            'ALTER TABLE notify_log ADD COLUMN on_pause INTEGER'
        )
        c_db.execute(
            'ALTER TABLE notify_log ADD COLUMN on_resume INTEGER'
        )
        c_db.execute(
            'ALTER TABLE notify_log ADD COLUMN on_buffer INTEGER'
        )

    # Upgrade notify_log table from earlier versions
    try:
        c_db.execute('SELECT on_created from notify_log')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table notify_log.")
        c_db.execute(
            'ALTER TABLE notify_log ADD COLUMN on_created INTEGER'
        )

    # Upgrade sessions table from earlier versions
    try:
        c_db.execute('SELECT buffer_count from sessions')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table sessions.")
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN buffer_count INTEGER DEFAULT 0'
        )
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN buffer_last_triggered INTEGER'
        )

    # Upgrade users table from earlier versions
    try:
        c_db.execute('SELECT custom_avatar_url from users')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table users.")
        c_db.execute(
            'ALTER TABLE users ADD COLUMN custom_avatar_url TEXT'
        )

    # Upgrade sessions table from earlier versions
    try:
        c_db.execute('SELECT last_paused from sessions')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table sessions.")
        c_db.execute(
            'ALTER TABLE sessions ADD COLUMN last_paused INTEGER'
        )

    # Add "Local" user to database as default unauthenticated user.
    result = c_db.execute('SELECT id FROM users WHERE username = "Local"')
    if not result.fetchone():
        logger.debug(u'User "Local" does not exist. Adding user.')
        c_db.execute('INSERT INTO users (user_id, username) VALUES (0, "Local")')

    # Upgrade session_history table from earlier versions
    try:
        c_db.execute('SELECT reference_id from session_history')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table session_history.")
        c_db.execute(
            'ALTER TABLE session_history ADD COLUMN reference_id INTEGER DEFAULT 0'
        )
        # Set reference_id to the first row where (user_id = previous row, rating_key != previous row) and user_id = user_id
        c_db.execute(
            'UPDATE session_history ' \
            'SET reference_id = (SELECT (CASE \
             WHEN (SELECT MIN(id) FROM session_history WHERE id > ( \
                 SELECT MAX(id) FROM session_history \
                 WHERE (user_id = t1.user_id AND rating_key <> t1.rating_key AND id < t1.id)) AND user_id = t1.user_id) IS NULL \
             THEN (SELECT MIN(id) FROM session_history WHERE (user_id = t1.user_id)) \
             ELSE (SELECT MIN(id) FROM session_history WHERE id > ( \
                 SELECT MAX(id) FROM session_history \
                 WHERE (user_id = t1.user_id AND rating_key <> t1.rating_key AND id < t1.id)) AND user_id = t1.user_id) END) ' \
            'FROM session_history AS t1 ' \
            'WHERE t1.id = session_history.id) '
        )

    # Upgrade users table from earlier versions
    try:
        c_db.execute('SELECT deleted_user from users')
    except sqlite3.OperationalError:
        logger.debug(u"Altering database. Updating database table users.")
        c_db.execute(
            'ALTER TABLE users ADD COLUMN deleted_user INTEGER DEFAULT 0'
        )

    conn_db.commit()
    c_db.close()

def shutdown(restart=False, update=False):
    cherrypy.engine.exit()
    SCHED.shutdown(wait=False)

    CONFIG.write()

    if not restart and not update:
        logger.info('PlexPy is shutting down...')

    if update:
        logger.info('PlexPy is updating...')
        try:
            versioncheck.update()
        except Exception as e:
            logger.warn('PlexPy failed to update: %s. Restarting.', e)

    if CREATEPID:
        logger.info('Removing pidfile %s', PIDFILE)
        os.remove(PIDFILE)

    if restart:
        logger.info('PlexPy is restarting...')
        popen_list = [sys.executable, FULL_PATH]
        popen_list += ARGS
        if '--nolaunch' not in popen_list:
            popen_list += ['--nolaunch']
        logger.info('Restarting PlexPy with %s', popen_list)
        subprocess.Popen(popen_list, cwd=os.getcwd())

    os._exit(0)

def generate_uuid():
    logger.debug(u"Generating UUID...")
    return uuid.uuid4().hex