apps/catalogue/models/listeners.py

   1 # -*- coding: utf-8 -*-
   2 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
   3 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
   4 #
   5 from django.conf import settings
   6 from django.core.cache import caches
   7 from django.db.models.signals import post_save, pre_delete, post_delete
   8 import django.dispatch
   9 from catalogue.models import Tag, BookMedia, Book, Fragment, Collection
  10 from catalogue import tasks
  11 from catalogue.utils import delete_from_cache_by_language
  12 from newtagging.models import tags_updated
  13
  14
  15 permanent_cache = caches['permanent']
  16
  17
  18 def _tags_updated_handler(sender, affected_tags, **kwargs):
  19     # reset tag global counter
  20     # we want Tag.changed_at updated for API to know the tag was touched
  21     for tag in affected_tags:
  22         tasks.touch_tag(tag)
  23
  24     # if book tags changed, reset book tag counter
  25     if isinstance(sender, Book) and \
  26                 Tag.objects.filter(pk__in=(tag.pk for tag in affected_tags)).\
  27                     exclude(category__in=('book', 'theme', 'set')).count():
  28         sender.reset_tag_counter()
  29     # if fragment theme changed, reset book theme counter
  30     elif isinstance(sender, Fragment) and \
  31                 Tag.objects.filter(pk__in=(tag.pk for tag in affected_tags)).\
  32                     filter(category='theme').count():
  33         sender.book.reset_theme_counter()
  34 tags_updated.connect(_tags_updated_handler)
  35
  36
  37 def _pre_delete_handler(sender, instance, **kwargs):
  38     """ refresh Book on BookMedia delete """
  39     if sender == BookMedia:
  40         instance.book.save()
  41 pre_delete.connect(_pre_delete_handler)
  42
  43
  44 def _post_delete_handler(sender, instance, **kwargs):
  45     """ refresh Book on BookMedia delete """
  46     if sender == Collection:
  47         delete_from_cache_by_language(permanent_cache, 'catalogue.collection:%s/%%s' % instance.slug)
  48         delete_from_cache_by_language(permanent_cache, 'catalogue.catalogue/%s')
  49 post_delete.connect(_post_delete_handler)
  50
  51
  52 def _post_save_handler(sender, instance, **kwargs):
  53     """ refresh all the short_html stuff on BookMedia update """
  54     if sender == BookMedia:
  55         instance.book.save()
  56         delete_from_cache_by_language(permanent_cache, 'catalogue.audiobook_list/%s')
  57         delete_from_cache_by_language(permanent_cache, 'catalogue.daisy_list/%s')
  58     elif sender == Collection:
  59         delete_from_cache_by_language(permanent_cache, 'catalogue.collection:%s/%%s' % instance.slug)
  60         delete_from_cache_by_language(permanent_cache, 'catalogue.catalogue/%s')
  61 post_save.connect(_post_save_handler)
  62
  63
  64 def post_publish(sender, **kwargs):
  65     delete_from_cache_by_language(permanent_cache, 'catalogue.book_list/%s')
  66     delete_from_cache_by_language(permanent_cache, 'catalogue.catalogue/%s')
  67 Book.published.connect(post_publish)
  68
  69
  70 if not settings.NO_SEARCH_INDEX:
  71     @django.dispatch.receiver(post_delete, sender=Book)
  72     def _remove_book_from_index_handler(sender, instance, **kwargs):
  73         """ remove the book from search index, when it is deleted."""
  74         from search.index import Index
  75         idx = Index()
  76         idx.remove_book(instance)
  77         idx.index_tags()