mygpo/data/podcast.py

   1 #
   2 # This file is part of my.gpodder.org.
   3 #
   4 # my.gpodder.org is free software: you can redistribute it and/or modify it
   5 # under the terms of the GNU Affero General Public License as published by
   6 # the Free Software Foundation, either version 3 of the License, or (at your
   7 # option) any later version.
   8 #
   9 # my.gpodder.org is distributed in the hope that it will be useful, but
  10 # WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  11 # or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public
  12 # License for more details.
  13 #
  14 # You should have received a copy of the GNU Affero General Public License
  15 # along with my.gpodder.org. If not, see <http://www.gnu.org/licenses/>.
  16 #
  17
  18 from collections import Counter
  19
  20 from mygpo.db.couchdb.podcast_state import subscribed_users, \
  21          subscribed_podcast_ids_by_user_id
  22
  23
  24 def calc_similar_podcasts(podcast, num=20):
  25     """
  26     calculates and returns a list of podcasts that seem to be similar
  27     to the given one.
  28
  29     Probably an expensive operation
  30     """
  31
  32     users = subscribed_users(podcast)
  33
  34     podcasts = Counter()
  35
  36     for user_id in users:
  37         user_subscriptions = subscribed_podcast_ids_by_user_id(user_id)
  38         user_counter = Counter(user_subscriptions)
  39         podcasts.update(user_counter)
  40
  41     return podcasts.most_common(num)