mygpo/directory/tags.py

   1 from random import choice
   2
   3 from django.db import IntegrityError
   4 from django.utils.text import slugify
   5
   6 from mygpo.decorators import query_if_required
   7 from mygpo.categories.models import Category, CategoryEntry
   8
   9
  10 class Topics(object):
  11
  12     def __init__(self, total=100, num_cat=10, podcasts_per_cat=10):
  13         self.total = total
  14         self.num_cat = num_cat
  15         self.podcasts_per_cat = podcasts_per_cat
  16         self._categories = None
  17         self._tagcloud = None
  18
  19     def _needs_query(self):
  20         return self._categories is None
  21
  22     def _query(self):
  23         categories = list(Category.objects.filter(num_entries__gt=0)
  24                                   .filter(tags__isnull=False)
  25                                   .order_by('-modified')[:self.total]
  26                                   .prefetch_related('tags'))
  27         self._categories = categories[:self.num_cat]
  28         self._tagcloud = sorted(categories[self.num_cat:],
  29                                 key=lambda x: x.title.lower())
  30
  31     @property
  32     @query_if_required()
  33     def tagcloud(self):
  34         return self._tagcloud
  35
  36     @query_if_required()
  37     def max_entries(self):
  38         return max([e.num_entries for e in self.tagcloud] + [0])
  39
  40     @query_if_required()
  41     def min_entries(self):
  42         return min([e.num_entries for e in self.tagcloud] + [0])
  43
  44     @property
  45     @query_if_required()
  46     def categories(self):
  47         return self._categories
  48
  49
  50 def update_category(podcast):
  51     all_tags = list(t.tag for t in podcast.tags.all())
  52
  53     if not all_tags:
  54         return
  55
  56     random_tag = choice(all_tags).strip()
  57
  58     try:
  59         category, created = Category.objects.get_or_create(
  60             tags__tag=slugify(random_tag),
  61             defaults={
  62                 'title': random_tag,
  63             }
  64         )
  65
  66     except IntegrityError as ie:
  67         # check if category with this title already exists
  68         # the exception message should be like:
  69         # IntegrityError: duplicate key value violates unique
  70         # constraint "categories_category_title_key"
  71         if 'categories_category_title_key' not in str(ie):
  72             raise
  73
  74         category = Category.objects.get(title=random_tag)
  75         created = False
  76
  77     if not created:
  78         # update modified timestamp
  79         category.save()
  80
  81     # add podcast to the category as newest entry
  82     entry, created = CategoryEntry.objects.get_or_create(
  83         category=category,
  84         podcast=podcast,
  85     )
  86
  87     if not created:
  88         # update modified timestamp
  89         entry.save()