mygpo/db/couchdb/directory.py

   1 from collections import defaultdict, Counter
   2 from operator import itemgetter
   3
   4 from mygpo.directory.models import Category
   5 from mygpo.db.couchdb import get_main_database
   6 from mygpo.cache import cache_result
   7 from mygpo.db.couchdb.utils import multi_request_view
   8 from mygpo.db import QueryParameterMissing
   9
  10
  11 @cache_result(timeout=60*60)
  12 def category_for_tag(tag):
  13
  14     if not tag:
  15         raise QueryParameterMissing('tag')
  16
  17     r = Category.view('categories/by_tags',
  18             key          = tag,
  19             include_docs = True,
  20             stale        = 'update_after',
  21         )
  22     return r.first() if r else None
  23
  24
  25 @cache_result(timeout=60*60)
  26 def top_categories(offset, count, with_podcasts=False):
  27
  28     if offset is None:
  29         raise QueryParameterMissing('offset')
  30
  31     if not count:
  32         raise QueryParameterMissing('count')
  33
  34
  35     if with_podcasts:
  36         r = Category.view('categories/by_update',
  37                 descending   = True,
  38                 skip         = offset,
  39                 limit        = count,
  40                 include_docs = True,
  41                 stale        = 'update_after'
  42             )
  43
  44     else:
  45         db = get_main_database()
  46         r = db.view('categories/by_update',
  47                 descending   = True,
  48                 skip         = offset,
  49                 limit        = count,
  50                 stale        = 'update_after',
  51                 wrapper      = _category_wrapper,
  52             )
  53
  54     return list(r)
  55
  56
  57 def _category_wrapper(r):
  58     c = Category()
  59     c.label = r['value'][0]
  60     c._weight = r['value'][1]
  61     return c
  62
  63
  64 def tags_for_podcast(podcast):
  65     """ all tags for the podcast, in decreasing order of importance """
  66
  67     if not podcast:
  68         raise QueryParameterMissing('podcast')
  69
  70
  71     db = get_main_database()
  72     res = db.view('tags/by_podcast',
  73             startkey    = [podcast.get_id(), None],
  74             endkey      = [podcast.get_id(), {}],
  75             reduce      = True,
  76             group       = True,
  77             group_level = 2,
  78             stale       = 'update_after',
  79         )
  80
  81     tags = Counter(dict((x['key'][1], x['value']) for x in res))
  82
  83     res = db.view('usertags/by_podcast',
  84             startkey    = [podcast.get_id(), None],
  85             endkey      = [podcast.get_id(), {}],
  86             reduce      = True,
  87             group       = True,
  88             group_level = 2,
  89         )
  90
  91     tags.update(Counter(dict( (x['key'][1], x['value']) for x in res)))
  92
  93     get_tag = itemgetter(0)
  94     return map(get_tag, tags.most_common())
  95
  96
  97 def tags_for_user(user, podcast_id=None):
  98     """ mapping of all podcasts tagged by the user with a list of tags """
  99
 100     if not user:
 101         raise QueryParameterMissing('user')
 102
 103
 104     db = get_main_database()
 105     res = db.view('tags/by_user',
 106             startkey = [user._id, podcast_id],
 107             endkey   = [user._id, podcast_id or {}]
 108         )
 109
 110     tags = defaultdict(list)
 111     for r in res:
 112         tags[r['key'][1]].append(r['value'])
 113     return tags
 114
 115
 116 def all_tags():
 117     """ Returns all tags
 118
 119     Some tags might be returned twice """
 120     db = get_main_database()
 121     res = multi_request_view(db, 'podcasts/by_tag',
 122             wrap        = False,
 123             reduce      = True,
 124             group       = True,
 125             group_level = 1
 126         )
 127
 128     for r in res:
 129         yield r['key'][0]
 130
 131     res = multi_request_view(db, 'usertags/podcasts',
 132             wrap        = False,
 133             reduce      = True,
 134             group       = True,
 135             group_level = 1
 136         )
 137
 138     for r in res:
 139         yield r['key'][0]
 140
 141
 142 @cache_result(timeout=60*60)
 143 def toplist(res_cls, view, key, limit, **view_args):
 144
 145     if not limit:
 146         raise QueryParameterMissing('limit')
 147
 148
 149     r = res_cls.view(view,
 150             startkey     = key + [{}],
 151             endkey       = key + [None],
 152             include_docs = True,
 153             descending   = True,
 154             limit        = limit,
 155             stale        = 'update_after',
 156             **view_args
 157         )
 158     return list(r)