sima/core.py

   1 # -*- coding: utf-8 -*-
   2 """Core Object dealing with plugins and player client
   3 """
   4
   5 __version__ = '0.12.0.b'
   6 __author__ = 'kaliko jack'
   7 __url__ = 'git://git.kaliko.me/sima.git'
   8
   9 import sys
  10 import time
  11
  12 from collections import deque
  13 from logging import getLogger
  14
  15 from .client import PlayerClient
  16 from .client import PlayerError, PlayerUnHandledError
  17 from .lib.simadb import SimaDB
  18 from .lib.daemon import Daemon
  19
  20 class Sima(Daemon):
  21     """Main class, plugin and player management
  22     """
  23
  24     def __init__(self, conf):
  25         ## Set daemon
  26         Daemon.__init__(self, conf.get('daemon', 'pidfile'))
  27         self.enabled = True
  28         self.config = conf
  29         self.sdb = SimaDB(db_path=conf.get('sima', 'db_file'))
  30         self.log = getLogger('sima')
  31         self.plugins = list()
  32         self.player = self.__get_player()  # Player client
  33         try:
  34             self.player.connect()
  35         except (PlayerError, PlayerUnHandledError) as err:
  36             self.log.error('Fails to connect player: {}'.format(err))
  37             self.shutdown()
  38         self.short_history = deque(maxlen=60)
  39
  40     def __get_player(self):
  41         """Instanciate the player"""
  42         host = self.config.get('MPD', 'host')
  43         port = self.config.get('MPD', 'port')
  44         pswd = self.config.get('MPD', 'password', fallback=None)
  45         return PlayerClient(host, port, pswd)
  46
  47     def add_history(self):
  48         self.short_history.appendleft(self.player.current)
  49
  50     def register_plugin(self, plugin_class):
  51         """Registers plubin in Sima instance..."""
  52         self.plugins.append(plugin_class(self))
  53
  54     def foreach_plugin(self, method, *args, **kwds):
  55         """Plugin's callbacks dispatcher"""
  56         for plugin in self.plugins:
  57             #self.log.debug('dispatching {0} to {1}'.format(method, plugin))
  58             getattr(plugin, method)(*args, **kwds)
  59
  60     def need_tracks(self):
  61         if not self.enabled:
  62             self.log.debug('Queueing disabled!')
  63             return False
  64         queue = self.player.queue
  65         queue_trigger = self.config.getint('sima', 'queue_length')
  66         self.log.debug('Currently {0} track(s) ahead. (target {1})'.format(
  67                        len(queue), queue_trigger))
  68         if len(queue) < queue_trigger:
  69             return True
  70         return False
  71
  72     def queue(self):
  73         to_add = list()
  74         for plugin in self.plugins:
  75             pl_callback =  getattr(plugin, 'callback_need_track')()
  76             if pl_callback:
  77                 to_add.extend(pl_callback)
  78         if not to_add:
  79             self.log.warning('Queue plugins returned nothing!')
  80             for plugin in self.plugins:
  81                 pl_callback =  getattr(plugin, 'callback_need_track_fb')()
  82                 if pl_callback:
  83                     to_add.extend(pl_callback)
  84         for track in to_add:
  85             self.player.add(track)
  86
  87     def reconnect_player(self):
  88         """Trying to reconnect cycling through longer timeout
  89         cycle : 5s 10s 1m 5m 20m 1h
  90         """
  91         sleepfor = [5, 10, 60, 300, 1200, 3600]
  92         while True:
  93             tmp = sleepfor.pop(0)
  94             sleepfor.append(tmp)
  95             self.log.info('Trying to reconnect in {:>4d} seconds'.format(tmp))
  96             time.sleep(tmp)
  97             try:
  98                 self.player.connect()
  99             except PlayerError:
 100                 continue
 101             except PlayerUnHandledError as err:
 102                 #TODO: unhandled Player exceptions
 103                 self.log.warning('Unhandled player exception: %s' % err)
 104             self.log.info('Got reconnected')
 105             break
 106
 107     def shutdown(self):
 108         """General shutdown method
 109         """
 110         self.log.warning('Starting shutdown.')
 111         self.player.disconnect()
 112         self.foreach_plugin('shutdown')
 113
 114         self.log.info('The way is shut, it was made by those who are dead. '
 115                       'And the dead keep it…')
 116         self.log.info('bye...')
 117         sys.exit(0)
 118
 119     def run(self):
 120         """
 121         """
 122         while 42:
 123             try:
 124                 self.loop()
 125             except PlayerUnHandledError as err:
 126                 #TODO: unhandled Player exceptions
 127                 self.log.warning('Unhandled player exception: {}'.format(err))
 128                 del(self.player)
 129                 self.player = PlayerClient()
 130                 time.sleep(10)
 131             except PlayerError as err:
 132                 self.log.warning('Player error: %s' % err)
 133                 self.reconnect_player()
 134
 135     def loop(self):
 136         """Dispatching callbacks to plugins
 137         """
 138         # hanging here untill a monitored event is raised in the player
 139         if getattr(self, 'changed', False): # first iteration exception
 140             self.changed = self.player.monitor()
 141         else:  # first iteration goes through else
 142             self.changed = ['playlist', 'player', 'skipped']
 143         self.log.debug('changed: {}'.format(', '.join(self.changed)))
 144         if 'playlist' in self.changed:
 145             self.foreach_plugin('callback_playlist')
 146         if ('player' in self.changed
 147             or 'options' in self.changed):
 148             self.foreach_plugin('callback_player')
 149         if 'database' in self.changed:
 150             self.foreach_plugin('callback_player_database')
 151         if 'skipped' in self.changed:
 152             if self.player.state == 'play':
 153                 self.log.info('Playing: {}'.format(self.player.current))
 154                 self.add_history()
 155                 self.foreach_plugin('callback_next_song')
 156         if self.need_tracks():
 157             self.queue()
 158
 159 # VIM MODLINE
 160 # vim: ai ts=4 sw=4 sts=4 expandtab