sima/plugins/lastfm.py

   1 # -*- coding: utf-8 -*-
   2 """
   3 Fetching similar artists from last.fm web services
   4 """
   5
   6 # standart library import
   7 import random
   8
   9 from collections import deque
  10 from hashlib import md5
  11
  12 # third parties componants
  13
  14 # local import
  15 from ..lib.plugin import Plugin
  16 from ..lib.simafm import SimaFM, XmlFMHTTPError, XmlFMNotFound, XmlFMError
  17 from ..lib.track import Track
  18
  19
  20 def cache(func):
  21     """Caching decorator"""
  22     def wrapper(*args, **kwargs):
  23         #pylint: disable=W0212,C0111
  24         cls = args[0]
  25         similarities = [art + str(match) for art, match in args[1]]
  26         hashedlst = md5(''.join(similarities).encode('utf-8')).hexdigest()
  27         if hashedlst in cls._cache.get('asearch'):
  28             cls.log.debug('cached request')
  29             results = cls._cache.get('asearch').get(hashedlst)
  30         else:
  31             results = func(*args, **kwargs)
  32             cls._cache.get('asearch').update({hashedlst:list(results)})
  33         random.shuffle(results)
  34         return results
  35     return wrapper
  36
  37
  38 class Lastfm(Plugin):
  39     """last.fm similar artists
  40     """
  41
  42     def __init__(self, daemon):
  43         Plugin.__init__(self, daemon)
  44         self.daemon_conf = daemon.config
  45         self.sdb = daemon.sdb
  46         self.history = daemon.short_history
  47         ##
  48         self.to_add = list()
  49         self._cache = None
  50         self._flush_cache()
  51         wrapper = {
  52                 'track': self._track,
  53                 'top': self._top,
  54                 'album': self._album,
  55                 }
  56         self.queue_mode = wrapper.get(self.plugin_conf.get('queue_mode'))
  57
  58     def _flush_cache(self):
  59         """
  60         Both flushes and instanciates _cache
  61         """
  62         if isinstance(self._cache, dict):
  63             self.log.info('Lastfm: Flushing cache!')
  64         else:
  65             self.log.info('Lastfm: Initialising cache!')
  66         self._cache = {
  67                 'artists': None,
  68                 'asearch': dict(),
  69                 'tsearch': dict(),
  70                 }
  71         self._cache['artists'] = frozenset(self.player.list('artist'))
  72
  73     def _cleanup_cache(self):
  74         """Avoid bloated cache
  75         """
  76         for _ , val in self._cache.items():
  77             if isinstance(val, dict):
  78                 while len(val) > 150:
  79                     val.popitem()
  80
  81     def get_history(self, artist):
  82         """Constructs list of Track for already played titles for an artist.
  83         """
  84         duration = self.daemon_conf.getint('sima', 'history_duration')
  85         tracks_from_db = self.sdb.get_history(duration=duration, artist=artist)
  86         # Construct Track() objects list from database history
  87         played_tracks = [Track(artist=tr[-1], album=tr[1], title=tr[2],
  88                                file=tr[3]) for tr in tracks_from_db]
  89         return played_tracks
  90
  91     def filter_track(self, tracks):
  92         """
  93         Extract one unplayed track from a Track object list.
  94             * not in history
  95             * not already in the queue
  96         """
  97         artist = tracks[0].artist
  98         black_list = self.player.queue + self.to_add
  99         not_in_hist = list(set(tracks) - set(self.get_history(artist=artist)))
 100         if not not_in_hist:
 101             self.log.debug('All tracks already played for "{}"'.format(artist))
 102         random.shuffle(not_in_hist)
 103         candidate = [ trk for trk in not_in_hist if trk not in black_list ]
 104         if not candidate:
 105             self.log.debug('Unable to find title to add' +
 106                           ' for "%s".' % artist)
 107             return None
 108         self.to_add.append(random.choice(candidate))
 109
 110     def _get_artists_list_reorg(self, alist):
 111         """
 112         Move around items in artists_list in order to play first not recently
 113         played artists
 114         """
 115         # TODO: move to utils as a decorator
 116         duration = self.daemon_conf.getint('sima', 'history_duration')
 117         art_in_hist = list()
 118         for trk in self.sdb.get_history(duration=duration,
 119                                         artists=alist):
 120             if trk[0] not in art_in_hist:
 121                 art_in_hist.append(trk[0])
 122         art_in_hist.reverse()
 123         art_not_in_hist = [ ar for ar in alist if ar not in art_in_hist ]
 124         random.shuffle(art_not_in_hist)
 125         art_not_in_hist.extend(art_in_hist)
 126         self.log.debug('history ordered: {}'.format(
 127                        ' / '.join(art_not_in_hist)))
 128         return art_not_in_hist
 129
 130     @cache
 131     def get_artists_from_player(self, similarities):
 132         """
 133         Look in player library for availability of similar artists in
 134         similarities
 135         """
 136         dynamic = int(self.plugin_conf.get('dynamic'))
 137         if dynamic <= 0:
 138             dynamic = 100
 139         similarity = int(self.plugin_conf.get('similarity'))
 140         results = list()
 141         similarities.reverse()
 142         while (len(results) < dynamic
 143             and len(similarities) > 0):
 144             art_pop, match = similarities.pop()
 145             if match < similarity:
 146                 break
 147             results.extend(self.player.fuzzy_find(art_pop))
 148         results and self.log.debug('Similarity: %d%%' % match) # pylint: disable=w0106
 149         return results
 150
 151     def lfm_similar_artists(self, artist=None):
 152         """
 153         Retrieve similar artists on last.fm server.
 154         """
 155         if artist is None:
 156             current = self.player.current
 157         else:
 158             current = artist
 159         simafm = SimaFM()
 160         # initialize artists deque list to construct from DB
 161         as_art = deque()
 162         as_artists = simafm.get_similar(artist=current.artist)
 163         self.log.debug('Requesting last.fm for "{0.artist}"'.format(current))
 164         try:
 165             [as_art.append((a, m)) for a, m in as_artists]
 166         except XmlFMHTTPError as err:
 167             self.log.warning('last.fm http error: %s' % err)
 168         except XmlFMNotFound as err:
 169             self.log.warning("last.fm: %s" % err)
 170         except XmlFMError as err:
 171             self.log.warning('last.fm module error: %s' % err)
 172         if as_art:
 173             self.log.debug('Fetched %d artist(s) from last.fm' % len(as_art))
 174         return as_art
 175
 176     def get_recursive_similar_artist(self):
 177         history = deque(self.history)
 178         history.popleft()
 179         ret_extra = list()
 180         depth = 0
 181         current = self.player.current
 182         extra_arts = list()
 183         while depth < int(self.plugin_conf.get('depth')):
 184             trk = history.popleft()
 185             if trk.artist in [trk.artist for trk in extra_arts]:
 186                 continue
 187             extra_arts.append(trk)
 188             depth += 1
 189             if len(history) == 0:
 190                 break
 191         self.log.info('EXTRA ARTS: {}'.format(
 192             '/'.join([trk.artist for trk in extra_arts])))
 193         for artist in extra_arts:
 194             self.log.debug('Looking for artist similar to "{0.artist}" as well'.format(artist))
 195             similar = self.lfm_similar_artists(artist=artist)
 196             similar = sorted(similar, key=lambda sim: sim[1], reverse=True)
 197             ret_extra.extend(self.get_artists_from_player(similar))
 198             if current.artist in ret_extra:
 199                 ret_extra.remove(current.artist)
 200         return ret_extra
 201
 202     def get_local_similar_artists(self):
 203         """Check against local player for similar artists fetched from last.fm
 204         """
 205         current = self.player.current
 206         self.log.info('Looking for artist similar to "{0.artist}"'.format(current))
 207         similar = self.lfm_similar_artists()
 208         if not similar:
 209             self.log.info('Got nothing from last.fm!')
 210             return []
 211         similar = sorted(similar, key=lambda sim: sim[1], reverse=True)
 212         self.log.info('First five similar artist(s): {}...'.format(
 213                       ' / '.join([a for a, m in similar[0:5]])))
 214         self.log.info('Looking availability in music library')
 215         ret = self.get_artists_from_player(similar)
 216         ret_extra = None
 217         if len(self.history) >= 2:
 218             ret_extra = self.get_recursive_similar_artist()
 219         if not ret:
 220             self.log.warning('Got nothing from music library.')
 221             self.log.warning('Try running in debug mode to guess why...')
 222             return []
 223         if ret_extra:
 224             ret = list(set(ret) | set(ret_extra))
 225         self.log.info('Got {} artists in library'.format(len(ret)))
 226         self.log.info(' / '.join(ret))
 227         # Move around similars items to get in unplayed|not recently played
 228         # artist first.
 229         return self._get_artists_list_reorg(ret)
 230
 231     def _track(self):
 232         """Get some tracks for track queue mode
 233         """
 234         artists = self.get_local_similar_artists()
 235         nbtracks_target = int(self.plugin_conf.get('track_to_add'))
 236         for artist in artists:
 237             self.log.debug('Trying to find titles to add for "{}"'.format(
 238                            artist))
 239             found = self.player.find_track(artist)
 240             # find tracks not in history for artist
 241             self.filter_track(found)
 242             if len(self.to_add) == nbtracks_target:
 243                 break
 244         if not self.to_add:
 245             self.log.debug('Found no unplayed tracks, is your ' +
 246                              'history getting too large?')
 247             return None
 248         for track in self.to_add:
 249             self.log.info('last.fm candidate: {0!s}'.format(track))
 250
 251     def _album(self):
 252         """Get albums for album queue mode
 253         """
 254         #artists = self.get_local_similar_artists()
 255         pass
 256
 257     def _top(self):
 258         """Get some tracks for top track queue mode
 259         """
 260         #artists = self.get_local_similar_artists()
 261         pass
 262
 263     def callback_need_track(self):
 264         self._cleanup_cache()
 265         if not self.player.current:
 266             self.log.info('Not currently playing track, cannot queue')
 267             return None
 268         self.queue_mode()
 269         candidates = self.to_add
 270         self.to_add = list()
 271         return candidates
 272
 273     def callback_player_database(self):
 274         self._flush_cache()
 275
 276 # VIM MODLINE
 277 # vim: ai ts=4 sw=4 sts=4 expandtab