mygpo/suggestions/tasks.py

   1 from itertools import chain
   2 from collections import Counter
   3
   4 from mygpo.celery import celery
   5 from mygpo.subscriptions import get_subscribed_podcasts
   6 from mygpo.suggestions.models import PodcastSuggestion
   7
   8 from celery.utils.log import get_task_logger
   9 logger = get_task_logger(__name__)
  10
  11
  12 @celery.task
  13 def update_suggestions(user, max_suggestions=15):
  14     """ updates the suggestions of a user """
  15     logger.info('Updating suggestions of user {user.username}'.format(
  16         user=user))
  17
  18     # calculate possible suggestions
  19     subscribed_podcasts = [sp.podcast for sp in get_subscribed_podcasts(user)]
  20     logger.debug('Found {num_podcasts} subscribed podcasts'.format(
  21         num_podcasts=len(subscribed_podcasts)))
  22
  23     # TODO: update related_podcasts of the subscribed_podcasts?
  24
  25     related = list(chain.from_iterable([p.related_podcasts.all() for p
  26                                         in subscribed_podcasts]))
  27
  28     # get most relevant
  29     counter = Counter(related)
  30     logger.debug('Found {num_related} related podcasts'.format(
  31         num_related=len(counter)))
  32
  33     suggested = [p for p, count in counter.most_common(max_suggestions)]
  34
  35     for suggested_podcast in suggested:
  36         ps, created = PodcastSuggestion.objects.get_or_create(
  37             suggested_to=user,
  38             podcast=suggested_podcast,
  39         )
  40         if created:
  41             logger.info('Created suggestion for {podcast}'.format(
  42                 podcast=suggested_podcast))
  43
  44     user.profile.suggestions_up_to_date = True
  45     user.profile.save()