mygpo/api/backend.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 datetime import timedelta
  19 from collections import defaultdict
  20 from itertools import cycle
  21 import random
  22
  23 from django.core.cache import cache
  24
  25 from mygpo.data.mimetype import get_type, CONTENT_TYPES
  26 from mygpo.core.models import Podcast, Episode
  27 from mygpo.users.models import EpisodeUserState, Device, DeviceDoesNotExist
  28 from mygpo.decorators import repeat_on_conflict
  29 from mygpo.json import json
  30
  31
  32 def get_random_picks(languages=None):
  33     """ Returns random podcasts for the given language """
  34
  35     if not languages:
  36         for podcast in Podcast.random():
  37             yield podcast
  38
  39     counts = cache.get('podcast-language-counts')
  40     if not counts:
  41         counts = get_podcast_count_for_language()
  42         cache.set('podcast-language-counts', counts, 60*60)
  43
  44
  45     # extract positive counts of all languages in language param
  46     counts = filter(lambda (l, c): l in languages and c > 0, counts.items())
  47
  48     for lang, count in cycle(counts):
  49         skip = random.randint(0, count-1)
  50
  51         for podcast in Podcast.for_language(lang, skip=skip, limit=1):
  52             yield podcast
  53
  54
  55
  56 def get_podcast_count_for_language():
  57     """ Returns a the number of podcasts for each language """
  58
  59     counts = defaultdict(int)
  60
  61     db = Podcast.get_db()
  62     r = db.view('core/podcasts_by_language',
  63         reduce = True,
  64         group_level = 1,
  65         stale       = 'update_after',
  66     )
  67
  68     counts.update( dict( (x['key'][0], x['value']) for x in r) )
  69     return counts
  70
  71
  72
  73 def get_device(user, uid, user_agent, undelete=True):
  74     """
  75     Loads or creates the device indicated by user, uid.
  76
  77     If the device has been deleted and undelete=True, it is undeleted.
  78     """
  79
  80     store_ua = user.settings.get('store_user_agent', True)
  81
  82     @repeat_on_conflict(['user'])
  83     def _get(user, uid, undelete):
  84
  85         save = False
  86
  87         try:
  88             device = user.get_device_by_uid(uid, only_active=False)
  89
  90         except DeviceDoesNotExist:
  91             device = Device(uid=uid)
  92             user.devices.append(device)
  93             save = True
  94
  95         if device.deleted and undelete:
  96             device.deleted = False
  97             user.set_device(device)
  98             save = True
  99
 100         if store_ua and user_agent and \
 101                 getattr(device, 'user_agent', None) != user_agent:
 102             device.user_agent = user_agent
 103             user.set_device(device)
 104             save = True
 105
 106         if save:
 107             user.save()
 108
 109         return device
 110
 111     return _get(user=user, uid=uid, undelete=undelete)
 112
 113
 114 def get_favorites(user):
 115     favorites = Episode.view('users/favorite_episodes_by_user',
 116             key          = user._id,
 117             include_docs = True,
 118         )
 119     return favorites