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         # TODO: call cleanup once its dict instance are used somewhere XXX
  77         for _ , val in self._cache.items():
  78             if isinstance(val, dict):
  79                 while len(val) > 150:
  80                     val.popitem()
  81
  82     def get_history(self, artist):
  83         """Constructs list of Track for already played titles for an artist.
  84         """
  85         duration = self.daemon_conf.getint('sima', 'history_duration')
  86         tracks_from_db = self.sdb.get_history(duration=duration, artist=artist)
  87         # Construct Track() objects list from database history
  88         played_tracks = [Track(artist=tr[-1], album=tr[1], title=tr[2],
  89                                file=tr[3]) for tr in tracks_from_db]
  90         return played_tracks
  91
  92     def filter_track(self, tracks):
  93         """
  94         Extract one unplayed track from a Track object list.
  95             * not in history
  96             * not already in the queue
  97         """
  98         artist = tracks[0].artist
  99         black_list = self.player.queue + self.to_add
 100         not_in_hist = list(set(tracks) - set(self.get_history(artist=artist)))
 101         if not not_in_hist:
 102             self.log.debug('All tracks already played for "{}"'.format(artist))
 103         random.shuffle(not_in_hist)
 104         candidate = [ trk for trk in not_in_hist if trk not in black_list ]
 105         if not candidate:
 106             self.log.debug('Unable to find title to add' +
 107                           ' for "%s".' % artist)
 108             return None
 109         self.to_add.append(random.choice(candidate))
 110
 111     def _get_artists_list_reorg(self, alist):
 112         """
 113         Move around items in artists_list in order to play first not recently
 114         played artists
 115         """
 116         # TODO: move to utils as a decorator
 117         duration = self.daemon_conf.getint('sima', 'history_duration')
 118         art_in_hist = list()
 119         for trk in self.sdb.get_history(duration=duration,
 120                                         artists=alist):
 121             if trk[0] not in art_in_hist:
 122                 art_in_hist.append(trk[0])
 123         art_in_hist.reverse()
 124         art_not_in_hist = [ ar for ar in alist if ar not in art_in_hist ]
 125         random.shuffle(art_not_in_hist)
 126         art_not_in_hist.extend(art_in_hist)
 127         self.log.debug('history ordered: {}'.format(
 128                        ' / '.join(art_not_in_hist)))
 129         return art_not_in_hist
 130
 131     @cache
 132     def get_artists_from_player(self, similarities):
 133         """
 134         Look in player library for availability of similar artists in
 135         similarities
 136         """
 137         dynamic = int(self.plugin_conf.get('dynamic'))
 138         if dynamic <= 0:
 139             dynamic = 100
 140         similarity = int(self.plugin_conf.get('similarity'))
 141         results = list()
 142         similarities.reverse()
 143         while (len(results) < dynamic
 144             and len(similarities) > 0):
 145             art_pop, match = similarities.pop()
 146             if match < similarity:
 147                 break
 148             results.extend(self.player.fuzzy_find(art_pop))
 149         results and self.log.debug('Similarity: %d%%' % match) # pylint: disable=w0106
 150         return results
 151
 152     def lfm_similar_artists(self, artist=None):
 153         """
 154         Retrieve similar artists on last.fm server.
 155         """
 156         if artist is None:
 157             current = self.player.current
 158         else:
 159             current = artist
 160         simafm = SimaFM()
 161         # initialize artists deque list to construct from DB
 162         as_art = deque()
 163         as_artists = simafm.get_similar(artist=current.artist)
 164         self.log.debug('Requesting last.fm for "{0.artist}"'.format(current))
 165         try:
 166             [as_art.append((a, m)) for a, m in as_artists]
 167         except XmlFMHTTPError as err:
 168             self.log.warning('last.fm http error: %s' % err)
 169         except XmlFMNotFound as err:
 170             self.log.warning("last.fm: %s" % err)
 171         except XmlFMError as err:
 172             self.log.warning('last.fm module error: %s' % err)
 173         if as_art:
 174             self.log.debug('Fetched %d artist(s) from last.fm' % len(as_art))
 175         return as_art
 176
 177     def get_recursive_similar_artist(self):
 178         history = deque(self.history)
 179         history.popleft()
 180         ret_extra = list()
 181         depth = 0
 182         current = self.player.current
 183         extra_arts = list()
 184         while depth < int(self.plugin_conf.get('depth')):
 185             trk = history.popleft()
 186             if trk.artist in [trk.artist for trk in extra_arts]:
 187                 continue
 188             extra_arts.append(trk)
 189             depth += 1
 190             if len(history) == 0:
 191                 break
 192         self.log.info('EXTRA ARTS: {}'.format(
 193             '/'.join([trk.artist for trk in extra_arts])))
 194         for artist in extra_arts:
 195             self.log.debug('Looking for artist similar to "{0.artist}" as well'.format(artist))
 196             similar = self.lfm_similar_artists(artist=artist)
 197             similar = sorted(similar, key=lambda sim: sim[1], reverse=True)
 198             ret_extra.extend(self.get_artists_from_player(similar))
 199             if current.artist in ret_extra:
 200                 ret_extra.remove(current.artist)
 201         return ret_extra
 202
 203     def get_local_similar_artists(self):
 204         """Check against local player for similar artists fetched from last.fm
 205         """
 206         current = self.player.current
 207         self.log.info('Looking for artist similar to "{0.artist}"'.format(current))
 208         similar = self.lfm_similar_artists()
 209         if not similar:
 210             self.log.info('Got nothing from last.fm!')
 211             return []
 212         similar = sorted(similar, key=lambda sim: sim[1], reverse=True)
 213         self.log.info('First five similar artist(s): {}...'.format(
 214                       ' / '.join([a for a, m in similar[0:5]])))
 215         self.log.info('Looking availability in music library')
 216         ret = self.get_artists_from_player(similar)
 217         ret_extra = None
 218         if len(self.history) >= 2:
 219             ret_extra = self.get_recursive_similar_artist()
 220         if not ret:
 221             self.log.warning('Got nothing from music library.')
 222             self.log.warning('Try running in debug mode to guess why...')
 223             return []
 224         if ret_extra:
 225             ret = list(set(ret) | set(ret_extra))
 226         self.log.info('Got {} artists in library'.format(len(ret)))
 227         self.log.info(' / '.join(ret))
 228         # Move around similars items to get in unplayed|not recently played
 229         # artist first.
 230         return self._get_artists_list_reorg(ret)
 231
 232     def _track(self):
 233         """Get some tracks for track queue mode
 234         """
 235         artists = self.get_local_similar_artists()
 236         nbtracks_target = int(self.plugin_conf.get('track_to_add'))
 237         for artist in artists:
 238             self.log.debug('Trying to find titles to add for "{}"'.format(
 239                            artist))
 240             found = self.player.find_track(artist)
 241             # find tracks not in history
 242             self.filter_track(found)
 243             if len(self.to_add) == nbtracks_target:
 244                 break
 245         if not self.to_add:
 246             self.log.debug('Found no unplayed tracks, is your ' +
 247                              'history getting too large?')
 248             return None
 249         for track in self.to_add:
 250             self.log.info('last.fm candidate: {0!s}'.format(track))
 251
 252     def _album(self):
 253         """Get albums for album queue mode
 254         """
 255         #artists = self.get_local_similar_artists()
 256         pass
 257
 258     def _top(self):
 259         """Get some tracks for top track queue mode
 260         """
 261         #artists = self.get_local_similar_artists()
 262         pass
 263
 264     def callback_need_track(self):
 265         self._cleanup_cache()
 266         if not self.player.current:
 267             self.log.info('Not currently playing track, cannot queue')
 268             return None
 269         self.queue_mode()
 270         candidates = self.to_add
 271         self.to_add = list()
 272         return candidates
 273
 274     def callback_player_database(self):
 275         self._flush_cache()
 276
 277 # VIM MODLINE
 278 # vim: ai ts=4 sw=4 sts=4 expandtab