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