mygpo/core/podcasts.py

   1 from itertools import chain, islice
   2
   3 try:
   4     import gevent
   5 except ImportError:
   6     gevent = None
   7
   8 from mygpo.core.models import Podcast
   9 from mygpo.core.proxy import proxy_object
  10 from mygpo.db.couchdb.episode import episodes_for_podcast
  11
  12
  13 class PodcastSet(set):
  14     """ Represents a set of podcasts """
  15
  16     def __init__(self, podcasts=None):
  17         self.podcasts = podcasts or []
  18
  19
  20     def get_newest_episodes(self, max_date, num_episodes, max_per_podcast=5):
  21         """ Returns the newest episodes for a set of podcasts """
  22
  23         podcast_key = lambda p: p.latest_episode_timestamp
  24
  25         podcasts = filter(lambda p: p.latest_episode_timestamp, self.podcasts)
  26         podcasts = sorted(podcasts, key=podcast_key, reverse=True)
  27
  28         # we need at most num_episodes podcasts
  29         podcasts = podcasts[:num_episodes]
  30
  31         podcast_dict = dict((p.get_id(), p) for p in podcasts)
  32
  33         if gevent:
  34             jobs = [gevent.spawn(episodes_for_podcast, podcast, since=1,
  35                     until=max_date, descending=True,
  36                     limit=max_per_podcast) for podcast in podcasts]
  37
  38             gevent.joinall(jobs)
  39
  40             episodes = chain.from_iterable(job.get() for job in jobs)
  41
  42         else:
  43             episodes = [episodes_for_podcast(podcast, since=1,
  44                     until=max_date, descending=True,
  45                     limit=max_per_podcast) for podcast in podcasts]
  46
  47
  48         episodes = sorted(episodes, key=lambda e: e.released, reverse=True)
  49
  50         for episode in islice(episodes, num_episodes):
  51             p = podcast_dict.get(episode.podcast, None)
  52             yield proxy_object(episode, podcast=p)