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 from catalogue.helpers import cached_in_field
  13 from catalogue.models import BookPublishRecord, ChunkPublishRecord
  14 from catalogue.tasks import refresh_instance, book_content_updated
  15 from catalogue.xml_tools import compile_text, split_xml
  16
  17
  18 class Book(models.Model):
  19     """ A document edited on the wiki """
  20
  21     title = models.CharField(_('title'), max_length=255, db_index=True)
  22     slug = models.SlugField(_('slug'), max_length=128, unique=True, db_index=True)
  23     public = models.BooleanField(_('public'), default=True, db_index=True)
  24     gallery = models.CharField(_('scan gallery name'), max_length=255, blank=True)
  25
  26     #wl_slug = models.CharField(_('title'), max_length=255, null=True, db_index=True, editable=False)
  27     parent = models.ForeignKey('self', null=True, blank=True, verbose_name=_('parent'), related_name="children", editable=False)
  28     parent_number = models.IntegerField(_('parent number'), null=True, blank=True, db_index=True, editable=False)
  29
  30     # Cache
  31     _short_html = models.TextField(null=True, blank=True, editable=False)
  32     _single = models.NullBooleanField(editable=False, db_index=True)
  33     _new_publishable = models.NullBooleanField(editable=False)
  34     _published = models.NullBooleanField(editable=False)
  35     dc_slug = models.CharField(max_length=128, null=True, blank=True,
  36             editable=False, db_index=True)
  37
  38     class NoTextError(BaseException):
  39         pass
  40
  41     class Meta:
  42         app_label = 'catalogue'
  43         ordering = ['title', 'slug']
  44         verbose_name = _('book')
  45         verbose_name_plural = _('books')
  46
  47
  48     # Representing
  49     # ============
  50
  51     def __iter__(self):
  52         return iter(self.chunk_set.all())
  53
  54     def __getitem__(self, chunk):
  55         return self.chunk_set.all()[chunk]
  56
  57     def __len__(self):
  58         return self.chunk_set.count()
  59
  60     def __nonzero__(self):
  61         """
  62             Necessary so that __len__ isn't used for bool evaluation.
  63         """
  64         return True
  65
  66     def __unicode__(self):
  67         return self.title
  68
  69     @models.permalink
  70     def get_absolute_url(self):
  71         return ("catalogue_book", [self.slug])
  72
  73     def correct_about(self):
  74         return "http://%s%s" % (
  75             Site.objects.get_current().domain,
  76             self.get_absolute_url()
  77         )
  78
  79     # Creating & manipulating
  80     # =======================
  81
  82     def accessible(self, request):
  83         return self.public or request.user.is_authenticated()
  84
  85     @classmethod
  86     @transaction.commit_on_success
  87     def create(cls, creator, text, *args, **kwargs):
  88         b = cls.objects.create(*args, **kwargs)
  89         b.chunk_set.all().update(creator=creator)
  90         b[0].commit(text, author=creator)
  91         return b
  92
  93     def add(self, *args, **kwargs):
  94         """Add a new chunk at the end."""
  95         return self.chunk_set.reverse()[0].split(*args, **kwargs)
  96
  97     @classmethod
  98     @transaction.commit_on_success
  99     def import_xml_text(cls, text=u'', previous_book=None,
 100                 commit_args=None, **kwargs):
 101         """Imports a book from XML, splitting it into chunks as necessary."""
 102         texts = split_xml(text)
 103         if previous_book:
 104             instance = previous_book
 105         else:
 106             instance = cls(**kwargs)
 107             instance.save()
 108
 109         # if there are more parts, set the rest to empty strings
 110         book_len = len(instance)
 111         for i in range(book_len - len(texts)):
 112             texts.append((u'pusta część %d' % (i + 1), u''))
 113
 114         i = 0
 115         for i, (title, text) in enumerate(texts):
 116             if not title:
 117                 title = u'część %d' % (i + 1)
 118
 119             slug = slughifi(title)
 120
 121             if i < book_len:
 122                 chunk = instance[i]
 123                 chunk.slug = slug[:50]
 124                 chunk.title = title[:255]
 125                 chunk.save()
 126             else:
 127                 chunk = instance.add(slug, title)
 128
 129             chunk.commit(text, **commit_args)
 130
 131         return instance
 132
 133     def make_chunk_slug(self, proposed):
 134         """
 135             Finds a chunk slug not yet used in the book.
 136         """
 137         slugs = set(c.slug for c in self)
 138         i = 1
 139         new_slug = proposed[:50]
 140         while new_slug in slugs:
 141             new_slug = "%s_%d" % (proposed[:45], i)
 142             i += 1
 143         return new_slug
 144
 145     @transaction.commit_on_success
 146     def append(self, other, slugs=None, titles=None):
 147         """Add all chunks of another book to self."""
 148         assert self != other
 149
 150         number = self[len(self) - 1].number + 1
 151         len_other = len(other)
 152         single = len_other == 1
 153
 154         if slugs is not None:
 155             assert len(slugs) == len_other
 156         if titles is not None:
 157             assert len(titles) == len_other
 158             if slugs is None:
 159                 slugs = [slughifi(t) for t in titles]
 160
 161         for i, chunk in enumerate(other):
 162             # move chunk to new book
 163             chunk.book = self
 164             chunk.number = number
 165
 166             if titles is None:
 167                 # try some title guessing
 168                 if other.title.startswith(self.title):
 169                     other_title_part = other.title[len(self.title):].lstrip(' /')
 170                 else:
 171                     other_title_part = other.title
 172
 173                 if single:
 174                     # special treatment for appending one-parters:
 175                     # just use the guessed title and original book slug
 176                     chunk.title = other_title_part
 177                     if other.slug.startswith(self.slug):
 178                         chunk.slug = other.slug[len(self.slug):].lstrip('-_')
 179                     else:
 180                         chunk.slug = other.slug
 181                 else:
 182                     chunk.title = ("%s, %s" % (other_title_part, chunk.title))[:255]
 183             else:
 184                 chunk.slug = slugs[i]
 185                 chunk.title = titles[i]
 186
 187             chunk.slug = self.make_chunk_slug(chunk.slug)
 188             chunk.save()
 189             number += 1
 190         assert not other.chunk_set.exists()
 191         other.delete()
 192
 193     @transaction.commit_on_success
 194     def prepend_history(self, other):
 195         """Prepend history from all the other book's chunks to own."""
 196         assert self != other
 197
 198         for i in range(len(self), len(other)):
 199             title = u"pusta część %d" % i
 200             chunk = self.add(slughifi(title), title)
 201             chunk.commit('')
 202
 203         for i in range(len(other)):
 204             self[i].prepend_history(other[0])
 205
 206         assert not other.chunk_set.exists()
 207         other.delete()
 208
 209
 210     # State & cache
 211     # =============
 212
 213     def last_published(self):
 214         try:
 215             return self.publish_log.all()[0].timestamp
 216         except IndexError:
 217             return None
 218
 219     def assert_publishable(self):
 220         assert self.chunk_set.exists(), _('No chunks in the book.')
 221         try:
 222             changes = self.get_current_changes(publishable=True)
 223         except self.NoTextError:
 224             raise AssertionError(_('Not all chunks have publishable revisions.'))
 225         book_xml = self.materialize(changes=changes)
 226
 227         from librarian.dcparser import BookInfo
 228         from librarian import NoDublinCore, ParseError, ValidationError
 229
 230         try:
 231             bi = BookInfo.from_string(book_xml.encode('utf-8'))
 232         except ParseError, e:
 233             raise AssertionError(_('Invalid XML') + ': ' + str(e))
 234         except NoDublinCore:
 235             raise AssertionError(_('No Dublin Core found.'))
 236         except ValidationError, e:
 237             raise AssertionError(_('Invalid Dublin Core') + ': ' + str(e))
 238
 239         valid_about = self.correct_about()
 240         assert bi.about == valid_about, _("rdf:about is not") + " " + valid_about
 241
 242     def hidden(self):
 243         return self.slug.startswith('.')
 244
 245     def is_new_publishable(self):
 246         """Checks if book is ready for publishing.
 247
 248         Returns True if there is a publishable version newer than the one
 249         already published.
 250
 251         """
 252         new_publishable = False
 253         if not self.chunk_set.exists():
 254             return False
 255         for chunk in self:
 256             change = chunk.publishable()
 257             if not change:
 258                 return False
 259             if not new_publishable and not change.publish_log.exists():
 260                 new_publishable = True
 261         return new_publishable
 262     new_publishable = cached_in_field('_new_publishable')(is_new_publishable)
 263
 264     def is_published(self):
 265         return self.publish_log.exists()
 266     published = cached_in_field('_published')(is_published)
 267
 268     def is_single(self):
 269         return len(self) == 1
 270     single = cached_in_field('_single')(is_single)
 271
 272     @cached_in_field('_short_html')
 273     def short_html(self):
 274         return render_to_string('catalogue/book_list/book.html', {'book': self})
 275
 276     def book_info(self, publishable=True):
 277         try:
 278             book_xml = self.materialize(publishable=publishable)
 279         except self.NoTextError:
 280             pass
 281         else:
 282             from librarian.dcparser import BookInfo
 283             from librarian import NoDublinCore, ParseError, ValidationError
 284             try:
 285                 return BookInfo.from_string(book_xml.encode('utf-8'))
 286             except (self.NoTextError, ParseError, NoDublinCore, ValidationError):
 287                 return None
 288
 289     def refresh_dc_cache(self):
 290         update = {
 291             'dc_slug': None,
 292         }
 293
 294         info = self.book_info()
 295         if info is not None:
 296             update['dc_slug'] = info.slug
 297         Book.objects.filter(pk=self.pk).update(**update)
 298
 299     def touch(self):
 300         # this should only really be done when text or publishable status changes
 301         book_content_updated.delay(self)
 302
 303         update = {
 304             "_new_publishable": self.is_new_publishable(),
 305             "_published": self.is_published(),
 306             "_single": self.is_single(),
 307             "_short_html": None,
 308         }
 309         Book.objects.filter(pk=self.pk).update(**update)
 310         refresh_instance(self)
 311
 312     def refresh(self):
 313         """This should be done offline."""
 314         self.short_html
 315         self.single
 316         self.new_publishable
 317         self.published
 318
 319     # Materializing & publishing
 320     # ==========================
 321
 322     def get_current_changes(self, publishable=True):
 323         """
 324             Returns a list containing one Change for every Chunk in the Book.
 325             Takes the most recent revision (publishable, if set).
 326             Throws an error, if a proper revision is unavailable for a Chunk.
 327         """
 328         if publishable:
 329             changes = [chunk.publishable() for chunk in self]
 330         else:
 331             changes = [chunk.head for chunk in self if chunk.head is not None]
 332         if None in changes:
 333             raise self.NoTextError('Some chunks have no available text.')
 334         return changes
 335
 336     def materialize(self, publishable=False, changes=None):
 337         """
 338             Get full text of the document compiled from chunks.
 339             Takes the current versions of all texts
 340             or versions most recently tagged for publishing,
 341             or a specified iterable changes.
 342         """
 343         if changes is None:
 344             changes = self.get_current_changes(publishable)
 345         return compile_text(change.materialize() for change in changes)
 346
 347     def publish(self, user):
 348         """
 349             Publishes a book on behalf of a (local) user.
 350         """
 351         import apiclient
 352         from catalogue.signals import post_publish
 353
 354         self.assert_publishable()
 355         changes = self.get_current_changes(publishable=True)
 356         book_xml = self.materialize(changes=changes)
 357         apiclient.api_call(user, "books/", {"book_xml": book_xml})
 358         # record the publish
 359         br = BookPublishRecord.objects.create(book=self, user=user)
 360         for c in changes:
 361             ChunkPublishRecord.objects.create(book_record=br, change=c)
 362         post_publish.send(sender=br)