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 get_cache
   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 newtagging.models import tags_updated
  12
  13
  14 permanent_cache = get_cache('permanent')
  15
  16
  17 def _tags_updated_handler(sender, affected_tags, **kwargs):
  18     # reset tag global counter
  19     # we want Tag.changed_at updated for API to know the tag was touched
  20     for tag in affected_tags:
  21         tasks.touch_tag(tag)
  22
  23     # if book tags changed, reset book tag counter
  24     if isinstance(sender, Book) and \
  25                 Tag.objects.filter(pk__in=(tag.pk for tag in affected_tags)).\
  26                     exclude(category__in=('book', 'theme', 'set')).count():
  27         sender.reset_tag_counter()
  28     # if fragment theme changed, reset book theme counter
  29     elif isinstance(sender, Fragment) and \
  30                 Tag.objects.filter(pk__in=(tag.pk for tag in affected_tags)).\
  31                     filter(category='theme').count():
  32         sender.book.reset_theme_counter()
  33 tags_updated.connect(_tags_updated_handler)
  34
  35
  36 def _pre_delete_handler(sender, instance, **kwargs):
  37     """ refresh Book on BookMedia delete """
  38     if sender == BookMedia:
  39         instance.book.save()
  40 pre_delete.connect(_pre_delete_handler)
  41
  42
  43 def _post_save_handler(sender, instance, **kwargs):
  44     """ refresh all the short_html stuff on BookMedia update """
  45     if sender == BookMedia:
  46         instance.book.save()
  47     elif sender == Collection:
  48         permanent_cache.delete('catalogue.collection:%s' % instance.slug)
  49 post_save.connect(_post_save_handler)
  50
  51
  52 def post_publish(sender, **kwargs):
  53     permanent_cache.delete_many(['catalogue.book_list',
  54             'catalogue.audiobook_list', 'catalogue.daisy_list'])
  55 Book.published.connect(post_publish)
  56
  57
  58 if not settings.NO_SEARCH_INDEX:
  59     @django.dispatch.receiver(post_delete, sender=Book)
  60     def _remove_book_from_index_handler(sender, instance, **kwargs):
  61         """ remove the book from search index, when it is deleted."""
  62         import search
  63         search.JVM.attachCurrentThread()
  64         idx = search.Index()
  65         idx.open(timeout=10000)  # 10 seconds timeout.
  66         try:
  67             idx.remove_book(instance)
  68             idx.index_tags()
  69         finally:
  70             idx.close()