X-Git-Url: https://git.mdrn.pl/wolnelektury.git/blobdiff_plain/07e5d48b0655d447b2dec96ad6e5e81e72ec4837..7bf7f12fe0175bc3bd3e87580ec062d010420001:/apps/catalogue/models.py diff --git a/apps/catalogue/models.py b/apps/catalogue/models.py index 4ef0a14e6..2202cc103 100644 --- a/apps/catalogue/models.py +++ b/apps/catalogue/models.py @@ -11,7 +11,9 @@ from django.template.loader import render_to_string from django.utils.safestring import mark_safe from django.utils.translation import get_language from django.core.urlresolvers import reverse -from datetime import datetime +from django.db.models.signals import post_save, m2m_changed, pre_delete + +from django.conf import settings from newtagging.models import TagBase, tags_updated from newtagging import managers @@ -19,6 +21,7 @@ from catalogue.fields import JSONField from librarian import dcparser, html, epub, NoDublinCore from mutagen import id3 +from slughifi import slughifi TAG_CATEGORIES = ( @@ -31,6 +34,12 @@ TAG_CATEGORIES = ( ('book', _('book')), ) +MEDIA_FORMATS = ( + ('odt', _('ODT file')), + ('mp3', _('MP3 file')), + ('ogg', _('OGG file')), + ('daisy', _('DAISY file')), +) class TagSubcategoryManager(models.Manager): def __init__(self, subcategory): @@ -44,18 +53,20 @@ class TagSubcategoryManager(models.Manager): class Tag(TagBase): name = models.CharField(_('name'), max_length=50, db_index=True) slug = models.SlugField(_('slug'), max_length=120, db_index=True) - sort_key = models.SlugField(_('sort key'), max_length=120, db_index=True) + sort_key = models.CharField(_('sort key'), max_length=120, db_index=True) category = models.CharField(_('category'), max_length=50, blank=False, null=False, db_index=True, choices=TAG_CATEGORIES) description = models.TextField(_('description'), blank=True) main_page = models.BooleanField(_('main page'), default=False, db_index=True, help_text=_('Show tag on main page')) user = models.ForeignKey(User, blank=True, null=True) - book_count = models.IntegerField(_('book count'), blank=False, null=True) - death = models.IntegerField(_(u'year of death'), blank=True, null=True) + book_count = models.IntegerField(_('book count'), blank=True, null=True) gazeta_link = models.CharField(blank=True, max_length=240) wiki_link = models.CharField(blank=True, max_length=240) + class UrlDeprecationWarning(DeprecationWarning): + pass + categories_rev = { 'autor': 'author', 'epoka': 'epoch', @@ -87,17 +98,6 @@ class Tag(TagBase): has_description.short_description = _('description') has_description.boolean = True - def alive(self): - return self.death is None - - def in_pd(self): - """ tests whether an author is in public domain """ - return self.death is not None and self.goes_to_pd() <= datetime.now().year - - def goes_to_pd(self): - """ calculates the year of public domain entry for an author """ - return self.death + 71 if self.death is not None else None - def get_count(self): """ returns global book count for book tags, fragment count for themes """ @@ -125,19 +125,20 @@ class Tag(TagBase): real_tags = [] ambiguous_slugs = [] category = None + deprecated = False tags_splitted = tags.split('/') - for index, name in enumerate(tags_splitted): - if name in Tag.categories_rev: + for name in tags_splitted: + if category: + real_tags.append(Tag.objects.get(slug=name, category=category)) + category = None + elif name in Tag.categories_rev: category = Tag.categories_rev[name] else: - if category: - real_tags.append(Tag.objects.get(slug=name, category=category)) - category = None - else: - try: - real_tags.append(Tag.objects.exclude(category='book').get(slug=name)) - except Tag.MultipleObjectsReturned, e: - ambiguous_slugs.append(name) + try: + real_tags.append(Tag.objects.exclude(category='book').get(slug=name)) + deprecated = True + except Tag.MultipleObjectsReturned, e: + ambiguous_slugs.append(name) if category: # something strange left off @@ -148,8 +149,11 @@ class Tag(TagBase): e.tags = real_tags e.ambiguous_slugs = ambiguous_slugs raise e - else: - return real_tags + if deprecated: + e = Tag.UrlDeprecationWarning() + e.tags = real_tags + raise e + return real_tags else: return TagBase.get_tag_list(tags) @@ -159,39 +163,89 @@ class Tag(TagBase): # TODO: why is this hard-coded ? -def book_upload_path(ext): - def get_dynamic_path(book, filename): - return 'lektura/%s.%s' % (book.slug, ext) +def book_upload_path(ext=None, maxlen=100): + def get_dynamic_path(media, filename, ext=ext): + # how to put related book's slug here? + if not ext: + if media.type == 'daisy': + ext = 'daisy.zip' + else: + ext = media.type + if not media.name: + name = slughifi(filename.split(".")[0]) + else: + name = slughifi(media.name) + return 'lektura/%s.%s' % (name[:maxlen-len('lektura/.%s' % ext)-4], ext) return get_dynamic_path -class Book(models.Model): - title = models.CharField(_('title'), max_length=120) - slug = models.SlugField(_('slug'), max_length=120, unique=True, db_index=True) - description = models.TextField(_('description'), blank=True) - created_at = models.DateTimeField(_('creation date'), auto_now=True) - _short_html = models.TextField(_('short HTML'), editable=False) - parent_number = models.IntegerField(_('parent number'), default=0) - extra_info = JSONField(_('extra information')) - gazeta_link = models.CharField(blank=True, max_length=240) - wiki_link = models.CharField(blank=True, max_length=240) +class BookMedia(models.Model): + type = models.CharField(_('type'), choices=MEDIA_FORMATS, max_length="100") + name = models.CharField(_('name'), max_length="100") + file = models.FileField(_('file'), upload_to=book_upload_path()) + uploaded_at = models.DateTimeField(_('creation date'), auto_now_add=True, editable=False) + extra_info = JSONField(_('extra information'), default='{}') + def book_count(self): + return self.book_set.count() + book_count.short_description = _('book count') - # Formats - xml_file = models.FileField(_('XML file'), upload_to=book_upload_path('xml'), blank=True) - html_file = models.FileField(_('HTML file'), upload_to=book_upload_path('html'), blank=True) - pdf_file = models.FileField(_('PDF file'), upload_to=book_upload_path('pdf'), blank=True) - epub_file = models.FileField(_('EPUB file'), upload_to=book_upload_path('epub'), blank=True) - odt_file = models.FileField(_('ODT file'), upload_to=book_upload_path('odt'), blank=True) - txt_file = models.FileField(_('TXT file'), upload_to=book_upload_path('txt'), blank=True) - mp3_file = models.FileField(_('MP3 file'), upload_to=book_upload_path('mp3'), blank=True) - ogg_file = models.FileField(_('OGG file'), upload_to=book_upload_path('ogg'), blank=True) + def books(self): + return mark_safe('
'.join("%s" % (reverse('admin:catalogue_book_change', args=[b.id]), b.title) for b in self.book_set.all())) + books.short_description = _('books') - parent = models.ForeignKey('self', blank=True, null=True, related_name='children') + def __unicode__(self): + return "%s (%s)" % (self.name, self.file.name.split("/")[-1]) - objects = models.Manager() - tagged = managers.ModelTaggedItemManager(Tag) - tags = managers.TagDescriptor(Tag) + class Meta: + ordering = ('type', 'name') + verbose_name = _('book media') + verbose_name_plural = _('book media') + + def save(self, force_insert=False, force_update=False, **kwargs): + media = super(BookMedia, self).save(force_insert, force_update, **kwargs) + if self.type == 'mp3': + file = self.file + extra_info = self.get_extra_info_value() + extra_info.update(self.get_mp3_info()) + self.set_extra_info_value(extra_info) + media = super(BookMedia, self).save(force_insert, force_update, **kwargs) + return media + + def get_mp3_info(self): + """Retrieves artist and director names from audio ID3 tags.""" + try: + audio = id3.ID3(self.file.path) + artist_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE1')) + director_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE3')) + except: + artist_name = director_name = '' + return {'artist_name': artist_name, 'director_name': director_name} + + +class Book(models.Model): + title = models.CharField(_('title'), max_length=120) + slug = models.SlugField(_('slug'), max_length=120, unique=True, db_index=True) + description = models.TextField(_('description'), blank=True) + created_at = models.DateTimeField(_('creation date'), auto_now_add=True) + _short_html = models.TextField(_('short HTML'), editable=False) + parent_number = models.IntegerField(_('parent number'), default=0) + extra_info = JSONField(_('extra information')) + gazeta_link = models.CharField(blank=True, max_length=240) + wiki_link = models.CharField(blank=True, max_length=240) + # files generated during publication + xml_file = models.FileField(_('XML file'), upload_to=book_upload_path('xml'), blank=True) + html_file = models.FileField(_('HTML file'), upload_to=book_upload_path('html'), blank=True) + pdf_file = models.FileField(_('PDF file'), upload_to=book_upload_path('pdf'), blank=True) + epub_file = models.FileField(_('EPUB file'), upload_to=book_upload_path('epub'), blank=True) + txt_file = models.FileField(_('TXT file'), upload_to=book_upload_path('txt'), blank=True) + # other files + medias = models.ManyToManyField(BookMedia, blank=True) + + parent = models.ForeignKey('self', blank=True, null=True, related_name='children') + objects = models.Manager() + tagged = managers.ModelTaggedItemManager(Tag) + tags = managers.TagDescriptor(Tag) _tag_counter = JSONField(null=True, editable=False) _theme_counter = JSONField(null=True, editable=False) @@ -207,7 +261,7 @@ class Book(models.Model): def __unicode__(self): return self.title - def save(self, force_insert=False, force_update=False, reset_short_html=True, refresh_mp3=True, **kwargs): + def save(self, force_insert=False, force_update=False, reset_short_html=True, **kwargs): if reset_short_html: # Reset _short_html during save update = {} @@ -217,16 +271,7 @@ class Book(models.Model): # Fragment.short_html relies on book's tags, so reset it here too self.fragments.all().update(**update) - book = super(Book, self).save(force_insert, force_update) - - if refresh_mp3 and self.mp3_file: - print self.mp3_file, self.mp3_file.path - extra_info = self.get_extra_info_value() - extra_info.update(self.get_mp3_info()) - self.set_extra_info_value(extra_info) - book = super(Book, self).save(force_insert, force_update) - - return book + return super(Book, self).save(force_insert, force_update) @permalink def get_absolute_url(self): @@ -244,10 +289,68 @@ class Book(models.Model): book_tag, created = Tag.objects.get_or_create(slug=slug, category='book') if created: book_tag.name = self.title[:50] - book_tag.sort_key = slug + book_tag.sort_key = self.title.lower() book_tag.save() return book_tag + def has_media(self, type): + if type == 'xml': + if self.xml_file: + return True + else: + return False + elif type == 'html': + if self.html_file: + return True + else: + return False + elif type == 'txt': + if self.txt_file: + return True + else: + return False + elif type == 'pdf': + if self.pdf_file: + return True + else: + return False + elif type == 'epub': + if self.epub_file: + return True + else: + return False + else: + if self.medias.filter(book=self, type=type).count() > 0: + return True + else: + return False + + def get_media(self, type): + if self.has_media(type): + if type == "xml": + return self.xml_file + elif type == "html": + return self.html_file + elif type == "epub": + return self.epub_file + elif type == "txt": + return self.txt_file + elif type == "pdf": + return self.pdf_file + else: + return self.medias.filter(book=self, type=type) + else: + return None + + def get_mp3(self): + return self.get_media("mp3") + def get_odt(self): + return self.get_media("odt") + def get_ogg(self): + return self.get_media("ogg") + def get_daisy(self): + return self.get_media("daisy") + def short_html(self): key = '_short_html_%s' % get_language() short_html = getattr(self, key) @@ -259,20 +362,18 @@ class Book(models.Model): tags = [mark_safe(u'%s' % (tag.get_absolute_url(), tag.name)) for tag in tags] formats = [] - if self.html_file: + # files generated during publication + if self.has_media("html"): formats.append(u'%s' % (reverse('book_text', kwargs={'slug': self.slug}), _('Read online'))) - if self.pdf_file: - formats.append(u'PDF' % self.pdf_file.url) - if self.epub_file: - formats.append(u'EPUB' % self.epub_file.url) - if self.odt_file: - formats.append(u'ODT' % self.odt_file.url) - if self.txt_file: - formats.append(u'TXT' % self.txt_file.url) - if self.mp3_file: - formats.append(u'MP3' % self.mp3_file.url) - if self.ogg_file: - formats.append(u'OGG' % self.ogg_file.url) + if self.has_media("pdf"): + formats.append(u'PDF' % self.get_media('pdf').url) + if self.root_ancestor.has_media("epub"): + formats.append(u'EPUB' % self.root_ancestor.get_media('epub').url) + if self.has_media("txt"): + formats.append(u'TXT' % self.get_media('txt').url) + # other files + for m in self.medias.order_by('type'): + formats.append(u'%s' % (m.file.url, m.type.upper())) formats = [mark_safe(format) for format in formats] @@ -282,18 +383,24 @@ class Book(models.Model): return mark_safe(getattr(self, key)) - def get_mp3_info(self): - """Retrieves artist and director names from audio ID3 tags.""" - audio = id3.ID3(self.mp3_file.path) - artist_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE1')) - director_name = ', '.join(', '.join(tag.text) for tag in audio.getall('TPE3')) - return {'artist_name': artist_name, 'director_name': director_name} + @property + def root_ancestor(self): + """ returns the oldest ancestor """ + + if not hasattr(self, '_root_ancestor'): + book = self + while book.parent: + book = book.parent + self._root_ancestor = book + return self._root_ancestor + def has_description(self): return len(self.description) > 0 has_description.short_description = _('description') has_description.boolean = True + # ugly ugly ugly def has_pdf_file(self): return bool(self.pdf_file) has_pdf_file.short_description = 'PDF' @@ -304,18 +411,93 @@ class Book(models.Model): has_epub_file.short_description = 'EPUB' has_epub_file.boolean = True - def has_odt_file(self): - return bool(self.odt_file) - has_odt_file.short_description = 'ODT' - has_odt_file.boolean = True + def has_txt_file(self): + return bool(self.txt_file) + has_txt_file.short_description = 'HTML' + has_txt_file.boolean = True def has_html_file(self): return bool(self.html_file) has_html_file.short_description = 'HTML' has_html_file.boolean = True + def has_odt_file(self): + return bool(self.has_media("odt")) + has_odt_file.short_description = 'ODT' + has_odt_file.boolean = True + + def has_mp3_file(self): + return bool(self.has_media("mp3")) + has_mp3_file.short_description = 'MP3' + has_mp3_file.boolean = True + + def has_ogg_file(self): + return bool(self.has_media("ogg")) + has_ogg_file.short_description = 'OGG' + has_ogg_file.boolean = True + + def has_daisy_file(self): + return bool(self.has_media("daisy")) + has_daisy_file.short_description = 'DAISY' + has_daisy_file.boolean = True + + def build_epub(self, remove_descendants=True): + """ (Re)builds the epub file. + If book has a parent, does nothing. + Unless remove_descendants is False, descendants' epubs are removed. + """ + + from StringIO import StringIO + from hashlib import sha1 + from django.core.files.base import ContentFile + from librarian import DocProvider + + class BookImportDocProvider(DocProvider): + """ used for joined EPUBs """ + + def __init__(self, book): + self.book = book + + def by_slug(self, slug): + if slug == self.book.slug: + return self.book.xml_file + else: + return Book.objects.get(slug=slug).xml_file + + if self.parent: + # don't need an epub + return + + epub_file = StringIO() + try: + epub.transform(BookImportDocProvider(self), self.slug, output_file=epub_file) + self.epub_file.save('%s.epub' % self.slug, ContentFile(epub_file.getvalue())) + FileRecord(slug=self.slug, type='epub', sha1=sha1(epub_file.getvalue()).hexdigest()).save() + except NoDublinCore: + pass + + book_descendants = list(self.children.all()) + while len(book_descendants) > 0: + child_book = book_descendants.pop(0) + if remove_descendants and child_book.has_epub_file(): + child_book.epub_file.delete() + # save anyway, to refresh short_html + child_book.save() + book_descendants += list(child_book.children.all()) + + def build_txt(self): + from StringIO import StringIO + from django.core.files.base import ContentFile + from librarian import text + + out = StringIO() + text.transform(open(self.xml_file.path), out) + self.txt_file.save('%s.txt' % self.slug, ContentFile(out.getvalue())) + self.save() + + @classmethod - def from_xml_file(cls, xml_file, overwrite=False): + def from_xml_file(cls, xml_file, **kwargs): # use librarian to parse meta-data book_info = dcparser.parse(xml_file) @@ -323,22 +505,32 @@ class Book(models.Model): xml_file = File(open(xml_file)) try: - return cls.from_text_and_meta(xml_file, book_info, overwrite) + return cls.from_text_and_meta(xml_file, book_info, **kwargs) finally: xml_file.close() @classmethod - def from_text_and_meta(cls, raw_file, book_info, overwrite=False): + def from_text_and_meta(cls, raw_file, book_info, overwrite=False, build_epub=True, build_txt=True): + import re from tempfile import NamedTemporaryFile - from slughifi import slughifi from markupstring import MarkupString - from hashlib import sha1 - from django.core.files.base import ContentFile from django.core.files.storage import default_storage - from StringIO import StringIO + + # check for parts before we do anything + children = [] + if hasattr(book_info, 'parts'): + for part_url in book_info.parts: + base, slug = part_url.rsplit('/', 1) + try: + children.append(Book.objects.get(slug=slug)) + except Book.DoesNotExist, e: + raise Book.DoesNotExist(_('Book with slug = "%s" does not exist.') % slug) + # Read book metadata book_base, book_slug = book_info.url.rsplit('/', 1) + if re.search(r'[^a-zA-Z0-9-]', book_slug): + raise ValueError('Invalid characters in slug') book, created = Book.objects.get_or_create(slug=book_slug) if created: @@ -369,49 +561,35 @@ class Book(models.Model): tag, created = Tag.objects.get_or_create(slug=slughifi(tag_name), category=category) if created: tag.name = tag_name - tag.sort_key = slughifi(tag_sort_key) + tag.sort_key = tag_sort_key.lower() tag.save() book_tags.append(tag) - book.tags = book_tags + book_shelves + book.tags = set(book_tags + book_shelves) book_tag = book.book_tag() - if hasattr(book_info, 'parts'): - for n, part_url in enumerate(book_info.parts): - base, slug = part_url.rsplit('/', 1) - try: - child_book = Book.objects.get(slug=slug) - child_book.parent = book - child_book.parent_number = n - child_book.save() - except Book.DoesNotExist, e: - raise Book.DoesNotExist(_('Book with slug = "%s" does not exist.') % slug) - - book_descendants = list(book.children.all()) - while len(book_descendants) > 0: - child_book = book_descendants.pop(0) - child_book.tags = list(child_book.tags) + [book_tag] + for n, child_book in enumerate(children): + child_book.parent = book + child_book.parent_number = n child_book.save() - for fragment in child_book.fragments.all(): - fragment.tags = set(list(fragment.tags) + [book_tag]) - book_descendants += list(child_book.children.all()) # Save XML and HTML files book.xml_file.save('%s.xml' % book.slug, raw_file, save=False) + # delete old fragments when overwriting + book.fragments.all().delete() + html_file = NamedTemporaryFile() if html.transform(book.xml_file.path, html_file, parse_dublincore=False): book.html_file.save('%s.html' % book.slug, File(html_file), save=False) - # Create EPUB - epub_file = StringIO() - try: - epub.transform(book.xml_file, epub_file) - book.epub_file.save('%s.epub' % book.slug, ContentFile(epub_file.getvalue()), save=False) - FileRecord(slug=book.slug, type='epub', sha1=sha1(epub_file.getvalue()).hexdigest()).save() - except NoDublinCore: - pass + # get ancestor l-tags for adding to new fragments + ancestor_tags = [] + p = book.parent + while p: + ancestor_tags.append(p.book_tag()) + p = p.parent # Extract fragments closed_fragments, open_fragments = html.extract_fragments(book.html_file.path) @@ -427,7 +605,7 @@ class Book(models.Model): tag, created = Tag.objects.get_or_create(slug=slughifi(theme_name), category='theme') if created: tag.name = theme_name - tag.sort_key = slughifi(theme_name) + tag.sort_key = theme_name.lower() tag.save() themes.append(tag) if not themes: @@ -441,11 +619,28 @@ class Book(models.Model): defaults={'text': text, 'short_text': short_text}) new_fragment.save() - new_fragment.tags = set(book_tags + themes + [book_tag]) + new_fragment.tags = set(book_tags + themes + [book_tag] + ancestor_tags) + + if not settings.NO_BUILD_TXT and build_txt: + book.build_txt() + + if not settings.NO_BUILD_EPUB and build_epub: + book.root_ancestor.build_epub() + + book_descendants = list(book.children.all()) + # add l-tag to descendants and their fragments + # delete unnecessary EPUB files + while len(book_descendants) > 0: + child_book = book_descendants.pop(0) + child_book.tags = list(child_book.tags) + [book_tag] + child_book.save() + for fragment in child_book.fragments.all(): + fragment.tags = set(list(fragment.tags) + [book_tag]) + book_descendants += list(child_book.children.all()) # refresh cache - book.tag_counter - book.theme_counter + book.reset_tag_counter() + book.reset_theme_counter() book.save() return book @@ -459,12 +654,12 @@ class Book(models.Model): for tag in self.tags.exclude(category__in=('book', 'theme', 'set')).order_by(): tags[tag.pk] = 1 self.set__tag_counter_value(tags) - self.save(reset_short_html=False, refresh_mp3=False) + self.save(reset_short_html=False) return tags def reset_tag_counter(self): self._tag_counter = None - self.save(reset_short_html=False, refresh_mp3=False) + self.save(reset_short_html=False) if self.parent: self.parent.reset_tag_counter() @@ -480,12 +675,12 @@ class Book(models.Model): for tag in fragment.tags.filter(category='theme').order_by(): tags[tag.pk] = tags.get(tag.pk, 0) + 1 self.set__theme_counter_value(tags) - self.save(reset_short_html=False, refresh_mp3=False) + self.save(reset_short_html=False) return tags def reset_theme_counter(self): self._theme_counter = None - self.save(reset_short_html=False, refresh_mp3=False) + self.save(reset_short_html=False) if self.parent: self.parent.reset_theme_counter() @@ -495,6 +690,22 @@ class Book(models.Model): return self.refresh_theme_counter() return dict((int(k), v) for k, v in self.get__theme_counter_value().iteritems()) + def pretty_title(self, html_links=False): + book = self + names = list(book.tags.filter(category='author')) + + books = [] + while book: + books.append(book) + book = book.parent + names.extend(reversed(books)) + + if html_links: + names = ['%s' % (tag.get_absolute_url(), tag.name) for tag in names] + else: + names = [tag.name for tag in names] + + return ', '.join(names) class Fragment(models.Model): @@ -528,34 +739,6 @@ class Fragment(models.Model): return mark_safe(getattr(self, key)) -class BookStub(models.Model): - title = models.CharField(_('title'), max_length=120) - author = models.CharField(_('author'), max_length=120) - pd = models.IntegerField(_('goes to public domain'), null=True, blank=True) - slug = models.SlugField(_('slug'), max_length=120, unique=True, db_index=True) - translator = models.TextField(_('translator'), blank=True) - translator_death = models.TextField(_('year of translator\'s death'), blank=True) - - class Meta: - ordering = ('title',) - verbose_name = _('book stub') - verbose_name_plural = _('book stubs') - - def __unicode__(self): - return self.title - - @permalink - def get_absolute_url(self): - return ('catalogue.views.book_detail', [self.slug]) - - def in_pd(self): - return self.pd is not None and self.pd <= datetime.now().year - - @property - def name(self): - return self.title - - class FileRecord(models.Model): slug = models.SlugField(_('slug'), max_length=120, db_index=True) type = models.CharField(_('type'), max_length=20, db_index=True) @@ -570,6 +753,12 @@ class FileRecord(models.Model): def __unicode__(self): return "%s %s.%s" % (self.sha1, self.slug, self.type) +########### +# +# SIGNALS +# +########### + def _tags_updated_handler(sender, affected_tags, **kwargs): # reset tag global counter @@ -587,3 +776,24 @@ def _tags_updated_handler(sender, affected_tags, **kwargs): sender.book.reset_theme_counter() tags_updated.connect(_tags_updated_handler) + +def _m2m_changed_handler(sender, instance, action, reverse, pk_set, **kwargs): + """ refresh all the short_html stuff on BookMedia delete """ + if sender == Book.medias.through and reverse and action == 'pre_clear': + for book in instance.book_set.all(): + book.save() +m2m_changed.connect(_m2m_changed_handler) + +def _pre_delete_handler(sender, instance, **kwargs): + """ explicitly clear m2m, so that Books can be refreshed """ + if sender == BookMedia: + instance.book_set.clear() +pre_delete.connect(_pre_delete_handler) + +def _post_save_handler(sender, instance, **kwargs): + """ refresh all the short_html stuff on BookMedia update """ + if sender == BookMedia: + for book in instance.book_set.all(): + book.save() +post_save.connect(_post_save_handler) +