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