mygpo/directory/tasks.py

   1 from datetime import datetime
   2
   3 from mygpo.core.models import SubscriberData
   4 from mygpo.cel import celery
   5 from mygpo.data.feeddownloader import PodcastUpdater
   6 from mygpo.db.couchdb.podcast import podcast_by_id, subscriberdata_for_podcast
   7 from mygpo.db.couchdb.podcast_state import podcast_subscriber_count
   8
   9
  10 @celery.task(max_retries=5)
  11 def update_podcast_subscribers(podcast_id):
  12     """ Updates the subscriber count of a podcast """
  13
  14     try:
  15         podcast = podcast_by_id(podcast_id)
  16
  17         # calculate current number of subscribers
  18         subscriber_count = podcast_subscriber_count(podcast)
  19         subs_cur = SubscriberData(timestamp=datetime.utcnow(),
  20                 subscriber_count=subscriber_count)
  21
  22         # sort all subscriber data entries
  23         subs_all = sorted(podcast.subscribers + [subs_cur],
  24                 key=lambda e: e.timestamp)
  25
  26         # move all but latest two to history
  27         subs_history = subscriberdata_for_podcast(podcast_id)
  28         subs_history.subscribers = subs_all[:-2]
  29         subs_history.save()
  30
  31         # move latest two to podcast
  32         podcast.subscribers = subs_all[-2:]
  33         podcast.save()
  34
  35     #TODO: which exceptions?
  36     except Exception as ex:
  37         raise update_podcast_subscribers.retry(exc=ex)