mygpo/db/couchdb/directory.py

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