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
  14 from catalogue.models import BookPublishRecord, ChunkPublishRecord
  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
  18
  19
  20 class Book(models.Model):
  21     """ A document edited on the wiki """
  22
  23     title = models.CharField(_('title'), max_length=255, db_index=True)
  24     slug = models.SlugField(_('slug'), max_length=128, unique=True, db_index=True)
  25     public = models.BooleanField(_('public'), default=True, db_index=True)
  26     gallery = models.CharField(_('scan gallery name'), max_length=255, blank=True)
  27
  28     #wl_slug = models.CharField(_('title'), max_length=255, null=True, db_index=True, editable=False)
  29     parent = models.ForeignKey('self', null=True, blank=True, verbose_name=_('parent'), related_name="children", editable=False)
  30     parent_number = models.IntegerField(_('parent number'), null=True, blank=True, db_index=True, editable=False)
  31
  32     # Cache
  33     _short_html = models.TextField(null=True, blank=True, editable=False)
  34     _single = models.NullBooleanField(editable=False, db_index=True)
  35     _new_publishable = models.NullBooleanField(editable=False)
  36     _published = models.NullBooleanField(editable=False)
  37     dc_slug = models.CharField(max_length=128, null=True, blank=True, editable=False)
  38
  39     class NoTextError(BaseException):
  40         pass
  41
  42     class Meta:
  43         app_label = 'catalogue'
  44         ordering = ['title', 'slug']
  45         verbose_name = _('book')
  46         verbose_name_plural = _('books')
  47
  48
  49     # Representing
  50     # ============
  51
  52     def __iter__(self):
  53         return iter(self.chunk_set.all())
  54
  55     def __getitem__(self, chunk):
  56         return self.chunk_set.all()[chunk]
  57
  58     def __len__(self):
  59         return self.chunk_set.count()
  60
  61     def __nonzero__(self):
  62         """
  63             Necessary so that __len__ isn't used for bool evaluation.
  64         """
  65         return True
  66
  67     def __unicode__(self):
  68         return self.title
  69
  70     @models.permalink
  71     def get_absolute_url(self):
  72         return ("catalogue_book", [self.slug])
  73
  74     def correct_about(self):
  75         return "http://%s%s" % (
  76             Site.objects.get_current().domain,
  77             self.get_absolute_url()
  78         )
  79
  80     # Creating & manipulating
  81     # =======================
  82
  83     def accessible(self, request):
  84         return self.public or request.user.is_authenticated()
  85
  86     @classmethod
  87     @transaction.commit_on_success
  88     def create(cls, creator, text, *args, **kwargs):
  89         b = cls.objects.create(*args, **kwargs)
  90         b.chunk_set.all().update(creator=creator)
  91         b[0].commit(text, author=creator)
  92         return b
  93
  94     def add(self, *args, **kwargs):
  95         """Add a new chunk at the end."""
  96         return self.chunk_set.reverse()[0].split(*args, **kwargs)
  97
  98     @classmethod
  99     @transaction.commit_on_success
 100     def import_xml_text(cls, text=u'', previous_book=None,
 101                 commit_args=None, **kwargs):
 102         """Imports a book from XML, splitting it into chunks as necessary."""
 103         texts = split_xml(text)
 104         if previous_book:
 105             instance = previous_book
 106         else:
 107             instance = cls(**kwargs)
 108             instance.save()
 109
 110         # if there are more parts, set the rest to empty strings
 111         book_len = len(instance)
 112         for i in range(book_len - len(texts)):
 113             texts.append((u'pusta część %d' % (i + 1), u''))
 114
 115         i = 0
 116         for i, (title, text) in enumerate(texts):
 117             if not title:
 118                 title = u'część %d' % (i + 1)
 119
 120             slug = slughifi(title)
 121
 122             if i < book_len:
 123                 chunk = instance[i]
 124                 chunk.slug = slug[:50]
 125                 chunk.title = title[:255]
 126                 chunk.save()
 127             else:
 128                 chunk = instance.add(slug, title)
 129
 130             chunk.commit(text, **commit_args)
 131
 132         return instance
 133
 134     def make_chunk_slug(self, proposed):
 135         """
 136             Finds a chunk slug not yet used in the book.
 137         """
 138         slugs = set(c.slug for c in self)
 139         i = 1
 140         new_slug = proposed[:50]
 141         while new_slug in slugs:
 142             new_slug = "%s_%d" % (proposed[:45], i)
 143             i += 1
 144         return new_slug
 145
 146     @transaction.commit_on_success
 147     def append(self, other, slugs=None, titles=None):
 148         """Add all chunks of another book to self."""
 149         assert self != other
 150
 151         number = self[len(self) - 1].number + 1
 152         len_other = len(other)
 153         single = len_other == 1
 154
 155         if slugs is not None:
 156             assert len(slugs) == len_other
 157         if titles is not None:
 158             assert len(titles) == len_other
 159             if slugs is None:
 160                 slugs = [slughifi(t) for t in titles]
 161
 162         for i, chunk in enumerate(other):
 163             # move chunk to new book
 164             chunk.book = self
 165             chunk.number = number
 166
 167             if titles is None:
 168                 # try some title guessing
 169                 if other.title.startswith(self.title):
 170                     other_title_part = other.title[len(self.title):].lstrip(' /')
 171                 else:
 172                     other_title_part = other.title
 173
 174                 if single:
 175                     # special treatment for appending one-parters:
 176                     # just use the guessed title and original book slug
 177                     chunk.title = other_title_part
 178                     if other.slug.startswith(self.slug):
 179                         chunk.slug = other.slug[len(self.slug):].lstrip('-_')
 180                     else:
 181                         chunk.slug = other.slug
 182                 else:
 183                     chunk.title = ("%s, %s" % (other_title_part, chunk.title))[:255]
 184             else:
 185                 chunk.slug = slugs[i]
 186                 chunk.title = titles[i]
 187
 188             chunk.slug = self.make_chunk_slug(chunk.slug)
 189             chunk.save()
 190             number += 1
 191         assert not other.chunk_set.exists()
 192         other.delete()
 193
 194     @transaction.commit_on_success
 195     def prepend_history(self, other):
 196         """Prepend history from all the other book's chunks to own."""
 197         assert self != other
 198
 199         for i in range(len(self), len(other)):
 200             title = u"pusta część %d" % i
 201             chunk = self.add(slughifi(title), title)
 202             chunk.commit('')
 203
 204         for i in range(len(other)):
 205             self[i].prepend_history(other[0])
 206
 207         assert not other.chunk_set.exists()
 208         other.delete()
 209
 210
 211     # State & cache
 212     # =============
 213
 214     def last_published(self):
 215         try:
 216             return self.publish_log.all()[0].timestamp
 217         except IndexError:
 218             return None
 219
 220     def assert_publishable(self):
 221         assert self.chunk_set.exists(), _('No chunks in the book.')
 222         try:
 223             changes = self.get_current_changes(publishable=True)
 224         except self.NoTextError:
 225             raise AssertionError(_('Not all chunks have publishable revisions.'))
 226         book_xml = self.materialize(changes=changes)
 227
 228         from librarian.dcparser import BookInfo
 229         from librarian import NoDublinCore, ParseError, ValidationError
 230
 231         try:
 232             bi = BookInfo.from_string(book_xml.encode('utf-8'))
 233         except ParseError, e:
 234             raise AssertionError(_('Invalid XML') + ': ' + str(e))
 235         except NoDublinCore:
 236             raise AssertionError(_('No Dublin Core found.'))
 237         except ValidationError, e:
 238             raise AssertionError(_('Invalid Dublin Core') + ': ' + str(e))
 239
 240         valid_about = self.correct_about()
 241         assert bi.about == valid_about, _("rdf:about is not") + " " + valid_about
 242
 243     def hidden(self):
 244         return self.slug.startswith('.')
 245
 246     def is_new_publishable(self):
 247         """Checks if book is ready for publishing.
 248
 249         Returns True if there is a publishable version newer than the one
 250         already published.
 251
 252         """
 253         new_publishable = False
 254         if not self.chunk_set.exists():
 255             return False
 256         for chunk in self:
 257             change = chunk.publishable()
 258             if not change:
 259                 return False
 260             if not new_publishable and not change.publish_log.exists():
 261                 new_publishable = True
 262         return new_publishable
 263     new_publishable = cached_in_field('_new_publishable')(is_new_publishable)
 264
 265     def is_published(self):
 266         return self.publish_log.exists()
 267     published = cached_in_field('_published')(is_published)
 268
 269     def is_single(self):
 270         return len(self) == 1
 271     single = cached_in_field('_single')(is_single)
 272
 273     @cached_in_field('_short_html')
 274     def short_html(self):
 275         return render_to_string('catalogue/book_list/book.html', {'book': self})
 276
 277     def book_info(self, publishable=True):
 278         try:
 279             book_xml = self.materialize(publishable=publishable)
 280         except self.NoTextError:
 281             pass
 282         else:
 283             from librarian.dcparser import BookInfo
 284             from librarian import NoDublinCore, ParseError, ValidationError
 285             try:
 286                 return BookInfo.from_string(book_xml.encode('utf-8'))
 287             except (self.NoTextError, ParseError, NoDublinCore, ValidationError):
 288                 return None
 289
 290     def refresh_dc_cache(self):
 291         update = {
 292             'dc_slug': None,
 293         }
 294
 295         info = self.book_info()
 296         if info is not None:
 297             update['dc_slug'] = info.slug
 298         Book.objects.filter(pk=self.pk).update(**update)
 299
 300     def touch(self):
 301         # this should only really be done when text or publishable status changes
 302         book_content_updated.delay(self)
 303
 304         update = {
 305             "_new_publishable": self.is_new_publishable(),
 306             "_published": self.is_published(),
 307             "_single": self.is_single(),
 308             "_short_html": None,
 309         }
 310         Book.objects.filter(pk=self.pk).update(**update)
 311         refresh_instance(self)
 312
 313     def refresh(self):
 314         """This should be done offline."""
 315         self.short_html
 316         self.single
 317         self.new_publishable
 318         self.published
 319
 320     # Materializing & publishing
 321     # ==========================
 322
 323     def get_current_changes(self, publishable=True):
 324         """
 325             Returns a list containing one Change for every Chunk in the Book.
 326             Takes the most recent revision (publishable, if set).
 327             Throws an error, if a proper revision is unavailable for a Chunk.
 328         """
 329         if publishable:
 330             changes = [chunk.publishable() for chunk in self]
 331         else:
 332             changes = [chunk.head for chunk in self if chunk.head is not None]
 333         if None in changes:
 334             raise self.NoTextError('Some chunks have no available text.')
 335         return changes
 336
 337     def materialize(self, publishable=False, changes=None):
 338         """
 339             Get full text of the document compiled from chunks.
 340             Takes the current versions of all texts
 341             or versions most recently tagged for publishing,
 342             or a specified iterable changes.
 343         """
 344         if changes is None:
 345             changes = self.get_current_changes(publishable)
 346         return compile_text(change.materialize() for change in changes)
 347
 348     def publish(self, user):
 349         """
 350             Publishes a book on behalf of a (local) user.
 351         """
 352         self.assert_publishable()
 353         changes = self.get_current_changes(publishable=True)
 354         book_xml = self.materialize(changes=changes)
 355         apiclient.api_call(user, "books/", {"book_xml": book_xml})
 356         # record the publish
 357         br = BookPublishRecord.objects.create(book=self, user=user)
 358         for c in changes:
 359             ChunkPublishRecord.objects.create(book_record=br, change=c)
 360         post_publish.send(sender=br)