mygpo/subscriptions/__init__.py

   1 import collections
   2
   3
   4 import logging
   5
   6 logger = logging.getLogger(__name__)
   7
   8 # we cannot import models in __init__.py, because it gets loaded while all
   9 # apps are loaded; ideally all these methods would be moved into a different
  10 # (non-__init__) module
  11
  12
  13 def get_subscribe_targets(podcast, user):
  14     """Clients / SyncGroup on which the podcast can be subscribed
  15
  16     This excludes all devices/syncgroups on which the podcast is already
  17     subscribed"""
  18
  19     # django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.
  20     from mygpo.users.models import Client
  21
  22     clients = (
  23         Client.objects.filter(user=user)
  24         .exclude(subscription__podcast=podcast, subscription__user=user)
  25         .select_related("sync_group")
  26     )
  27
  28     targets = set()
  29     for client in clients:
  30         if client.sync_group:
  31             targets.add(client.sync_group)
  32         else:
  33             targets.add(client)
  34
  35     return targets
  36
  37
  38 def get_subscribed_podcasts(user, only_public=False):
  39     """Returns all subscribed podcasts for the user
  40
  41     The attribute "url" contains the URL that was used when subscribing to
  42     the podcast"""
  43
  44     # django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.
  45     from mygpo.subscriptions.models import Subscription, SubscribedPodcast
  46
  47     subscriptions = (
  48         Subscription.objects.filter(user=user)
  49         .order_by("podcast")
  50         .distinct("podcast")
  51         .select_related("podcast")
  52     )
  53
  54     # django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.
  55     from mygpo.usersettings.models import UserSettings
  56
  57     private = UserSettings.objects.get_private_podcasts(user)
  58
  59     podcasts = []
  60     for subscription in subscriptions:
  61         podcast = subscription.podcast
  62         public = subscription.podcast not in private
  63
  64         # check if we want to include this podcast
  65         if only_public and not public:
  66             continue
  67
  68         subpodcast = SubscribedPodcast(podcast, public, subscription.ref_url)
  69         podcasts.append(subpodcast)
  70
  71     return podcasts
  72
  73
  74 def get_subscription_history(
  75     user, client=None, since=None, until=None, public_only=False
  76 ):
  77     """Returns chronologically ordered subscription history entries
  78
  79     Setting device_id restricts the actions to a certain device
  80     """
  81
  82     # django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.
  83     from mygpo.history.models import SUBSCRIPTION_ACTIONS, HistoryEntry
  84
  85     logger.info("Subscription History for {user}".format(user=user.username))
  86     history = (
  87         HistoryEntry.objects.filter(user=user)
  88         .filter(action__in=SUBSCRIPTION_ACTIONS)
  89         .order_by("timestamp")
  90     )
  91
  92     if client:
  93         logger.info("... client {client_uid}".format(client_uid=client.uid))
  94         history = history.filter(client=client)
  95
  96     if since:
  97         logger.info("... since {since}".format(since=since))
  98         history = history.filter(timestamp__gt=since)
  99
 100     if until:
 101         logger.info("... until {until}".format(until=until))
 102         history = history.filter(timestamp__lte=until)
 103
 104     if public_only:
 105         # django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.
 106         from mygpo.usersettings.models import UserSettings
 107
 108         logger.info("... only public")
 109         private = UserSettings.objects.get_private_podcasts(user)
 110         history = history.exclude(podcast__in=private)
 111
 112     return history
 113
 114
 115 def get_subscription_change_history(history):
 116     """Actions that added/removed podcasts from the subscription list
 117
 118     Returns an iterator of all subscription actions that either
 119      * added subscribed a podcast that hasn't been subscribed directly
 120        before the action (but could have been subscribed) earlier
 121      * removed a subscription of the podcast is not longer subscribed
 122        after the action
 123
 124     This method assumes, that no subscriptions exist at the beginning of
 125     ``history``.
 126     """
 127
 128     # django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.
 129     from mygpo.history.models import HistoryEntry
 130
 131     subscriptions = collections.defaultdict(int)
 132
 133     for entry in history:
 134         if entry.action == HistoryEntry.SUBSCRIBE:
 135             subscriptions[entry.podcast] += 1
 136
 137             # a new subscription has been added
 138             if subscriptions[entry.podcast] == 1:
 139                 yield entry
 140
 141         elif entry.action == HistoryEntry.UNSUBSCRIBE:
 142             subscriptions[entry.podcast] -= 1
 143
 144             # the last subscription has been removed
 145             if subscriptions[entry.podcast] == 0:
 146                 yield entry
 147
 148
 149 def subscription_diff(history):
 150     """Calculates a diff of subscriptions based on a history (sub/unsub)"""
 151
 152     # django.core.exceptions.AppRegistryNotReady: Apps aren't loaded yet.
 153     from mygpo.history.models import HistoryEntry
 154
 155     subscriptions = collections.defaultdict(int)
 156
 157     for entry in history:
 158         if entry.action == HistoryEntry.SUBSCRIBE:
 159             subscriptions[entry.podcast] += 1
 160
 161         elif entry.action == HistoryEntry.UNSUBSCRIBE:
 162             subscriptions[entry.podcast] -= 1
 163
 164     subscribe = [podcast for (podcast, value) in subscriptions.items() if value > 0]
 165     unsubscribe = [podcast for (podcast, value) in subscriptions.items() if value < 0]
 166
 167     return subscribe, unsubscribe