apps/catalogue/models/book.py

   1 # -*- coding: utf-8 -*-
   2 #
   3 # This file is part of FNP-Redakcja, licensed under GNU Affero GPLv3 or later.
   4 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
   5 #
   6 from django.contrib.sites.models import Site
   7 from django.db import models, transaction
   8 from django.template.loader import render_to_string
   9 from django.utils.translation import ugettext_lazy as _
  10 from slughifi import slughifi
  11
  12 import apiclient
  13 from catalogue.helpers import cached_in_field, GalleryMerger
  14 from catalogue.models import BookPublishRecord, ChunkPublishRecord, Project
  15 from catalogue.signals import post_publish
  16 from catalogue.tasks import refresh_instance, book_content_updated
  17 from catalogue.xml_tools import compile_text, split_xml, wl2_to_wl1
  18 from cover.models import Image
  19
  20
  21 class Book(models.Model):
  22     """ A document edited on the wiki """
  23
  24     title = models.CharField(_('title'), max_length=255, db_index=True)
  25     slug = models.SlugField(_('slug'), max_length=128, unique=True, db_index=True)
  26     public = models.BooleanField(_('public'), default=True, db_index=True)
  27     gallery = models.CharField(u'materiały', max_length=255, blank=True)
  28     project = models.ForeignKey(Project, null=True, blank=True)
  29
  30     # wl_slug = models.CharField(_('title'), max_length=255, null=True, db_index=True, editable=False)
  31     parent = models.ForeignKey(
  32         'self', null=True, blank=True, verbose_name=_('parent'), related_name="children", editable=False)
  33     parent_number = models.IntegerField(_('parent number'), null=True, blank=True, db_index=True, editable=False)
  34
  35     for_cybernauts = models.BooleanField(_('for Cybernauts'), default=False)
  36
  37     # Cache
  38     _short_html = models.TextField(null=True, blank=True, editable=False)
  39     _single = models.NullBooleanField(editable=False, db_index=True)
  40     _new_publishable = models.NullBooleanField(editable=False)
  41     _published = models.NullBooleanField(editable=False)
  42     _on_track = models.IntegerField(null=True, blank=True, db_index=True, editable=False)
  43     dc_cover_image = models.ForeignKey(
  44         Image, blank=True, null=True, db_index=True, on_delete=models.SET_NULL, editable=False)
  45     dc_slug = models.CharField(max_length=128, null=True, blank=True, editable=False, db_index=True)
  46
  47     class NoTextError(BaseException):
  48         pass
  49
  50     class Meta:
  51         app_label = 'catalogue'
  52         ordering = ['title', 'slug']
  53         verbose_name = u'moduł'
  54         verbose_name_plural = u'moduły'
  55
  56     # Representing
  57     # ============
  58
  59     def __iter__(self):
  60         return iter(self.chunk_set.all())
  61
  62     def __getitem__(self, chunk):
  63         return self.chunk_set.all()[chunk]
  64
  65     def __len__(self):
  66         return self.chunk_set.count()
  67
  68     def __nonzero__(self):
  69         """
  70             Necessary so that __len__ isn't used for bool evaluation.
  71         """
  72         return True
  73
  74     def __unicode__(self):
  75         return self.title
  76
  77     @models.permalink
  78     def get_absolute_url(self):
  79         return "catalogue_book", [self.slug]
  80
  81     def correct_about(self):
  82         return "http://%s%s" % (
  83             Site.objects.get_current().domain,
  84             self.get_absolute_url()
  85         )
  86
  87     # Creating & manipulating
  88     # =======================
  89
  90     def accessible(self, request):
  91         return self.public or request.user.is_authenticated()
  92
  93     @classmethod
  94     @transaction.commit_on_success
  95     def create(cls, creator, text, **kwargs):
  96         b = cls.objects.create(**kwargs)
  97         b.chunk_set.all().update(creator=creator)
  98         b[0].commit(text, author=creator)
  99         return b
 100
 101     def add(self, *args, **kwargs):
 102         """Add a new chunk at the end."""
 103         return self.chunk_set.reverse()[0].split(*args, **kwargs)
 104
 105     @classmethod
 106     @transaction.commit_on_success
 107     def import_xml_text(cls, text=u'', previous_book=None, commit_args=None, **kwargs):
 108         """Imports a book from XML, splitting it into chunks as necessary."""
 109         texts = split_xml(text)
 110         if previous_book:
 111             instance = previous_book
 112         else:
 113             instance = cls(**kwargs)
 114             instance.save()
 115
 116         # if there are more parts, set the rest to empty strings
 117         book_len = len(instance)
 118         for i in range(book_len - len(texts)):
 119             texts.append((u'pusta część %d' % (i + 1), u''))
 120
 121         for i, (title, text) in enumerate(texts):
 122             if not title:
 123                 title = u'część %d' % (i + 1)
 124
 125             slug = slughifi(title)
 126
 127             if i < book_len:
 128                 chunk = instance[i]
 129                 chunk.slug = slug[:50]
 130                 chunk.title = title[:255]
 131                 chunk.save()
 132             else:
 133                 chunk = instance.add(slug, title)
 134
 135             chunk.commit(text, **commit_args)
 136
 137         return instance
 138
 139     def make_chunk_slug(self, proposed):
 140         """
 141             Finds a chunk slug not yet used in the book.
 142         """
 143         slugs = set(c.slug for c in self)
 144         i = 1
 145         new_slug = proposed[:50]
 146         while new_slug in slugs:
 147             new_slug = "%s_%d" % (proposed[:45], i)
 148             i += 1
 149         return new_slug
 150
 151     @transaction.commit_on_success
 152     def append(self, other, slugs=None, titles=None):
 153         """Add all chunks of another book to self."""
 154         assert self != other
 155
 156         number = self[len(self) - 1].number + 1
 157         len_other = len(other)
 158         single = len_other == 1
 159
 160         if slugs is not None:
 161             assert len(slugs) == len_other
 162         if titles is not None:
 163             assert len(titles) == len_other
 164             if slugs is None:
 165                 slugs = [slughifi(t) for t in titles]
 166
 167         for i, chunk in enumerate(other):
 168             # move chunk to new book
 169             chunk.book = self
 170             chunk.number = number
 171
 172             if titles is None:
 173                 # try some title guessing
 174                 if other.title.startswith(self.title):
 175                     other_title_part = other.title[len(self.title):].lstrip(' /')
 176                 else:
 177                     other_title_part = other.title
 178
 179                 if single:
 180                     # special treatment for appending one-parters:
 181                     # just use the guessed title and original book slug
 182                     chunk.title = other_title_part
 183                     if other.slug.startswith(self.slug):
 184                         chunk.slug = other.slug[len(self.slug):].lstrip('-_')
 185                     else:
 186                         chunk.slug = other.slug
 187                 else:
 188                     chunk.title = ("%s, %s" % (other_title_part, chunk.title))[:255]
 189             else:
 190                 chunk.slug = slugs[i]
 191                 chunk.title = titles[i]
 192
 193             chunk.slug = self.make_chunk_slug(chunk.slug)
 194             chunk.save()
 195             number += 1
 196         assert not other.chunk_set.exists()
 197
 198         gm = GalleryMerger(self.gallery, other.gallery)
 199         self.gallery = gm.merge()
 200
 201         # and move the gallery starts
 202         if gm.was_merged:
 203             for chunk in self[len(self) - len_other:]:
 204                 old_start = chunk.gallery_start or 1
 205                 chunk.gallery_start = old_start + gm.dest_size - gm.num_deleted
 206                 chunk.save()
 207
 208         other.delete()
 209
 210     @transaction.commit_on_success
 211     def prepend_history(self, other):
 212         """Prepend history from all the other book's chunks to own."""
 213         assert self != other
 214
 215         for i in range(len(self), len(other)):
 216             title = u"pusta część %d" % i
 217             chunk = self.add(slughifi(title), title)
 218             chunk.commit('')
 219
 220         for i in range(len(other)):
 221             self[i].prepend_history(other[0])
 222
 223         assert not other.chunk_set.exists()
 224         other.delete()
 225
 226     def split(self):
 227         """Splits all the chunks into separate books."""
 228         for chunk in self:
 229             book = Book.objects.create(title=chunk.title, slug=chunk.slug, public=self.public, gallery=self.gallery)
 230             book[0].delete()
 231             chunk.book = book
 232             chunk.number = 1
 233             chunk.save()
 234         assert not self.chunk_set.exists()
 235         self.delete()
 236
 237     # State & cache
 238     # =============
 239
 240     def last_published(self):
 241         try:
 242             return self.publish_log.all()[0].timestamp
 243         except IndexError:
 244             return None
 245
 246     def assert_publishable(self):
 247         assert self.chunk_set.exists(), _('No chunks in the book.')
 248         try:
 249             changes = self.get_current_changes()
 250         except self.NoTextError:
 251             raise AssertionError(_('Not all chunks have publishable revisions.'))
 252
 253         from librarian import NoDublinCore, ParseError, ValidationError
 254
 255         try:
 256             bi = self.wldocument(changes=changes, strict=True).book_info
 257             if not bi.audience:
 258                 raise ValidationError('No audience specified')
 259             if not bi.type:
 260                 raise ValidationError('No type specified')
 261         except ParseError, e:
 262             raise AssertionError(_('Invalid XML') + ': ' + unicode(e))
 263         except NoDublinCore:
 264             raise AssertionError(_('No Dublin Core found.'))
 265         except ValidationError, e:
 266             raise AssertionError(_('Invalid Dublin Core') + ': ' + unicode(e))
 267
 268         valid_about = self.correct_about()
 269         assert bi.about == valid_about, _("rdf:about is not") + " " + valid_about
 270
 271     def publishable_error(self):
 272         try:
 273             return self.assert_publishable()
 274         except AssertionError, e:
 275             return e
 276
 277     def hidden(self):
 278         return self.slug.startswith('.')
 279
 280     def is_new_publishable(self):
 281         """Checks if book is ready for publishing.
 282
 283         Returns True if there is a publishable version newer than the one
 284         already published.
 285
 286         """
 287         new_publishable = False
 288         if not self.chunk_set.exists():
 289             return False
 290         for chunk in self:
 291             change = chunk.publishable()
 292             if not change:
 293                 return False
 294             if not new_publishable and not change.publish_log.exists():
 295                 new_publishable = True
 296         return new_publishable
 297     new_publishable = cached_in_field('_new_publishable')(is_new_publishable)
 298
 299     def is_published(self):
 300         return self.publish_log.exists()
 301     published = cached_in_field('_published')(is_published)
 302
 303     def get_on_track(self):
 304         if self.published:
 305             return -1
 306         stages = [ch.stage.ordering if ch.stage is not None else 0 for ch in self]
 307         if not len(stages):
 308             return 0
 309         return min(stages)
 310     on_track = cached_in_field('_on_track')(get_on_track)
 311
 312     def is_single(self):
 313         return len(self) == 1
 314     single = cached_in_field('_single')(is_single)
 315
 316     @cached_in_field('_short_html')
 317     def short_html(self):
 318         return render_to_string('catalogue/book_list/book.html', {'book': self})
 319
 320     def book_info(self, publishable=True):
 321         try:
 322             book_xml = self.wl1_xml(publishable=publishable)
 323         except self.NoTextError:
 324             pass
 325         else:
 326             from librarian.dcparser import BookInfo
 327             from librarian import NoDublinCore, ParseError, ValidationError
 328             try:
 329                 return BookInfo.from_string(book_xml)
 330             except (self.NoTextError, ParseError, NoDublinCore, ValidationError):
 331                 return None
 332
 333     def refresh_dc_cache(self):
 334         update = {
 335             'dc_slug': None,
 336             'dc_cover_image': None,
 337         }
 338
 339         info = self.book_info()
 340         if info is not None:
 341             update['dc_slug'] = info.url.slug
 342             if info.cover_source:
 343                 try:
 344                     image = Image.objects.get(pk=int(info.cover_source.rstrip('/').rsplit('/', 1)[-1]))
 345                 except Image.DoesNotExist:
 346                     pass
 347                 else:
 348                     if info.cover_source == image.get_full_url():
 349                         update['dc_cover_image'] = image
 350         Book.objects.filter(pk=self.pk).update(**update)
 351
 352     def touch(self):
 353         # this should only really be done when text or publishable status changes
 354         book_content_updated.delay(self)
 355
 356         update = {
 357             "_new_publishable": self.is_new_publishable(),
 358             "_published": self.is_published(),
 359             "_single": self.is_single(),
 360             "_on_track": self.get_on_track(),
 361             "_short_html": None,
 362         }
 363         Book.objects.filter(pk=self.pk).update(**update)
 364         refresh_instance(self)
 365
 366     def refresh(self):
 367         """This should be done offline."""
 368         self.short_html
 369         self.single
 370         self.new_publishable
 371         self.published
 372
 373     # Materializing & publishing
 374     # ==========================
 375
 376     def get_current_changes(self, publishable=True):
 377         """
 378             Returns a list containing one Change for every Chunk in the Book.
 379             Takes the most recent revision (publishable, if set).
 380             Throws an error, if a proper revision is unavailable for a Chunk.
 381         """
 382         if publishable:
 383             changes = [chunk.publishable() for chunk in self]
 384         else:
 385             changes = [chunk.head for chunk in self if chunk.head is not None]
 386         if None in changes:
 387             raise self.NoTextError('Some chunks have no available text.')
 388         return changes
 389
 390     def materialize(self, publishable=False, changes=None):
 391         """
 392             Get full text of the document compiled from chunks.
 393             Takes the current versions of all texts
 394             or versions most recently tagged for publishing,
 395             or a specified iterable changes.
 396         """
 397         if changes is None:
 398             changes = self.get_current_changes(publishable)
 399         return compile_text(change.materialize() for change in changes)
 400
 401     def wldocument(self, publishable=True, changes=None, parse_dublincore=True, strict=False):
 402         from catalogue.ebook_utils import RedakcjaDocProvider
 403         from librarian.parser import WLDocument
 404
 405         return WLDocument.from_string(
 406                 self.wl1_xml(publishable=publishable, changes=changes),
 407                 provider=RedakcjaDocProvider(publishable=publishable),
 408                 parse_dublincore=parse_dublincore,
 409                 strict=strict)
 410
 411     def publish(self, user, host=None):
 412         """
 413             Publishes a book on behalf of a (local) user.
 414         """
 415         import json
 416         import os
 417         from django.conf import settings
 418         self.assert_publishable()
 419         changes = self.get_current_changes()
 420         data = {"lesson_xml": self.wl1_xml(changes=changes)}
 421         if host:
 422             gallery_url = u'%s%s%s%s/' % (host, settings.MEDIA_URL, settings.IMAGE_DIR, self.slug)
 423             gallery_dir = os.path.join(settings.MEDIA_ROOT, settings.IMAGE_DIR, self.slug)
 424             if os.path.isdir(gallery_dir):
 425                 data['gallery_url'] = gallery_url
 426                 attachments = os.listdir(gallery_dir)
 427             else:
 428                 attachments = []
 429             data['attachments'] = json.dumps(attachments)
 430         apiclient.api_call(user, "lessons/", data)
 431         # record the publish
 432         br = BookPublishRecord.objects.create(book=self, user=user)
 433         for c in changes:
 434             ChunkPublishRecord.objects.create(book_record=br, change=c)
 435         post_publish.send(sender=br)
 436
 437     def wl1_xml(self, publishable=True, changes=None):
 438         return wl2_to_wl1(self.materialize(publishable=publishable, changes=changes), self.slug)