mygpo/search/index.py

   1
   2 """ Contains code for searching podcasts
   3
   4 Uses django.contrib.postgres.search for searching. See docs at
   5 https://docs.djangoproject.com/en/1.11/ref/contrib/postgres/search/
   6
   7 """
   8
   9 from django.conf import settings
  10
  11 from mygpo.podcasts.models import Podcast
  12
  13 from django.db.models import F, FloatField, ExpressionWrapper
  14 from django.contrib.postgres.search import SearchQuery, SearchRank
  15 from django.conf import settings
  16
  17 import logging
  18 logger = logging.getLogger(__name__)
  19
  20
  21 SEARCH_CUTOFF = settings.SEARCH_CUTOFF
  22
  23
  24 def search_podcasts(query):
  25     """ Search for podcasts according to 'query' """
  26
  27     logger.debug('Searching for "{query}" podcasts"', query=query)
  28
  29     query = SearchQuery(query)
  30
  31     results = Podcast.objects\
  32     .annotate(
  33         rank=SearchRank(F('search_vector'), query)
  34     )\
  35     .annotate(
  36         order=ExpressionWrapper(
  37             F('rank') * F('subscribers'),
  38             output_field=FloatField())
  39     )\
  40     .filter(rank__gte=SEARCH_CUTOFF)\
  41     .order_by('-order')
  42
  43     logger.debug('Found {count} podcasts for "{query}"', count=len(results),
  44                  query=query)
  45
  46     return results