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     _on_track = models.IntegerField(null=True, blank=True, db_index=True, editable=False)
  38     dc_slug = models.CharField(max_length=128, null=True, blank=True,
  39             editable=False, db_index=True)
  40
  41     class NoTextError(BaseException):
  42         pass
  43
  44     class Meta:
  45         app_label = 'catalogue'
  46         ordering = ['title', 'slug']
  47         verbose_name = _('book')
  48         verbose_name_plural = _('books')
  49
  50
  51     # Representing
  52     # ============
  53
  54     def __iter__(self):
  55         return iter(self.chunk_set.all())
  56
  57     def __getitem__(self, chunk):
  58         return self.chunk_set.all()[chunk]
  59
  60     def __len__(self):
  61         return self.chunk_set.count()
  62
  63     def __nonzero__(self):
  64         """
  65             Necessary so that __len__ isn't used for bool evaluation.
  66         """
  67         return True
  68
  69     def __unicode__(self):
  70         return self.title
  71
  72     @models.permalink
  73     def get_absolute_url(self):
  74         return ("catalogue_book", [self.slug])
  75
  76     def correct_about(self):
  77         return "http://%s%s" % (
  78             Site.objects.get_current().domain,
  79             self.get_absolute_url()
  80         )
  81
  82     # Creating & manipulating
  83     # =======================
  84
  85     def accessible(self, request):
  86         return self.public or request.user.is_authenticated()
  87
  88     @classmethod
  89     @transaction.commit_on_success
  90     def create(cls, creator, text, *args, **kwargs):
  91         b = cls.objects.create(*args, **kwargs)
  92         b.chunk_set.all().update(creator=creator)
  93         b[0].commit(text, author=creator)
  94         return b
  95
  96     def add(self, *args, **kwargs):
  97         """Add a new chunk at the end."""
  98         return self.chunk_set.reverse()[0].split(*args, **kwargs)
  99
 100     @classmethod
 101     @transaction.commit_on_success
 102     def import_xml_text(cls, text=u'', previous_book=None,
 103                 commit_args=None, **kwargs):
 104         """Imports a book from XML, splitting it into chunks as necessary."""
 105         texts = split_xml(text)
 106         if previous_book:
 107             instance = previous_book
 108         else:
 109             instance = cls(**kwargs)
 110             instance.save()
 111
 112         # if there are more parts, set the rest to empty strings
 113         book_len = len(instance)
 114         for i in range(book_len - len(texts)):
 115             texts.append((u'pusta część %d' % (i + 1), u''))
 116
 117         i = 0
 118         for i, (title, text) in enumerate(texts):
 119             if not title:
 120                 title = u'część %d' % (i + 1)
 121
 122             slug = slughifi(title)
 123
 124             if i < book_len:
 125                 chunk = instance[i]
 126                 chunk.slug = slug[:50]
 127                 chunk.title = title[:255]
 128                 chunk.save()
 129             else:
 130                 chunk = instance.add(slug, title)
 131
 132             chunk.commit(text, **commit_args)
 133
 134         return instance
 135
 136     def make_chunk_slug(self, proposed):
 137         """
 138             Finds a chunk slug not yet used in the book.
 139         """
 140         slugs = set(c.slug for c in self)
 141         i = 1
 142         new_slug = proposed[:50]
 143         while new_slug in slugs:
 144             new_slug = "%s_%d" % (proposed[:45], i)
 145             i += 1
 146         return new_slug
 147
 148     @transaction.commit_on_success
 149     def append(self, other, slugs=None, titles=None):
 150         """Add all chunks of another book to self."""
 151         assert self != other
 152
 153         number = self[len(self) - 1].number + 1
 154         len_other = len(other)
 155         single = len_other == 1
 156
 157         if slugs is not None:
 158             assert len(slugs) == len_other
 159         if titles is not None:
 160             assert len(titles) == len_other
 161             if slugs is None:
 162                 slugs = [slughifi(t) for t in titles]
 163
 164         for i, chunk in enumerate(other):
 165             # move chunk to new book
 166             chunk.book = self
 167             chunk.number = number
 168
 169             if titles is None:
 170                 # try some title guessing
 171                 if other.title.startswith(self.title):
 172                     other_title_part = other.title[len(self.title):].lstrip(' /')
 173                 else:
 174                     other_title_part = other.title
 175
 176                 if single:
 177                     # special treatment for appending one-parters:
 178                     # just use the guessed title and original book slug
 179                     chunk.title = other_title_part
 180                     if other.slug.startswith(self.slug):
 181                         chunk.slug = other.slug[len(self.slug):].lstrip('-_')
 182                     else:
 183                         chunk.slug = other.slug
 184                 else:
 185                     chunk.title = ("%s, %s" % (other_title_part, chunk.title))[:255]
 186             else:
 187                 chunk.slug = slugs[i]
 188                 chunk.title = titles[i]
 189
 190             chunk.slug = self.make_chunk_slug(chunk.slug)
 191             chunk.save()
 192             number += 1
 193         assert not other.chunk_set.exists()
 194         other.delete()
 195
 196     @transaction.commit_on_success
 197     def prepend_history(self, other):
 198         """Prepend history from all the other book's chunks to own."""
 199         assert self != other
 200
 201         for i in range(len(self), len(other)):
 202             title = u"pusta część %d" % i
 203             chunk = self.add(slughifi(title), title)
 204             chunk.commit('')
 205
 206         for i in range(len(other)):
 207             self[i].prepend_history(other[0])
 208
 209         assert not other.chunk_set.exists()
 210         other.delete()
 211
 212     def split(self):
 213         """Splits all the chunks into separate books."""
 214         self.title
 215         for chunk in self:
 216             book = Book.objects.create(title=chunk.title, slug=chunk.slug,
 217                     public=self.public, gallery=self.gallery)
 218             book[0].delete()
 219             chunk.book = book
 220             chunk.number = 1
 221             chunk.save()
 222         assert not self.chunk_set.exists()
 223         self.delete()
 224
 225     # State & cache
 226     # =============
 227
 228     def last_published(self):
 229         try:
 230             return self.publish_log.all()[0].timestamp
 231         except IndexError:
 232             return None
 233
 234     def assert_publishable(self):
 235         assert self.chunk_set.exists(), _('No chunks in the book.')
 236         try:
 237             changes = self.get_current_changes(publishable=True)
 238         except self.NoTextError:
 239             raise AssertionError(_('Not all chunks have publishable revisions.'))
 240         book_xml = self.materialize(changes=changes)
 241
 242         from librarian.dcparser import BookInfo
 243         from librarian import NoDublinCore, ParseError, ValidationError
 244
 245         try:
 246             bi = BookInfo.from_string(book_xml.encode('utf-8'))
 247         except ParseError, e:
 248             raise AssertionError(_('Invalid XML') + ': ' + str(e))
 249         except NoDublinCore:
 250             raise AssertionError(_('No Dublin Core found.'))
 251         except ValidationError, e:
 252             raise AssertionError(_('Invalid Dublin Core') + ': ' + str(e))
 253
 254         valid_about = self.correct_about()
 255         assert bi.about == valid_about, _("rdf:about is not") + " " + valid_about
 256
 257     def hidden(self):
 258         return self.slug.startswith('.')
 259
 260     def is_new_publishable(self):
 261         """Checks if book is ready for publishing.
 262
 263         Returns True if there is a publishable version newer than the one
 264         already published.
 265
 266         """
 267         new_publishable = False
 268         if not self.chunk_set.exists():
 269             return False
 270         for chunk in self:
 271             change = chunk.publishable()
 272             if not change:
 273                 return False
 274             if not new_publishable and not change.publish_log.exists():
 275                 new_publishable = True
 276         return new_publishable
 277     new_publishable = cached_in_field('_new_publishable')(is_new_publishable)
 278
 279     def is_published(self):
 280         return self.publish_log.exists()
 281     published = cached_in_field('_published')(is_published)
 282
 283     def get_on_track(self):
 284         if self.published:
 285             return -1
 286         stages = [ch.stage.ordering if ch.stage is not None else 0
 287                     for ch in self]
 288         if not len(stages):
 289             return 0
 290         return min(stages)
 291     on_track = cached_in_field('_on_track')(get_on_track)
 292
 293     def is_single(self):
 294         return len(self) == 1
 295     single = cached_in_field('_single')(is_single)
 296
 297     @cached_in_field('_short_html')
 298     def short_html(self):
 299         return render_to_string('catalogue/book_list/book.html', {'book': self})
 300
 301     def book_info(self, publishable=True):
 302         try:
 303             book_xml = self.materialize(publishable=publishable)
 304         except self.NoTextError:
 305             pass
 306         else:
 307             from librarian.dcparser import BookInfo
 308             from librarian import NoDublinCore, ParseError, ValidationError
 309             try:
 310                 return BookInfo.from_string(book_xml.encode('utf-8'))
 311             except (self.NoTextError, ParseError, NoDublinCore, ValidationError):
 312                 return None
 313
 314     def refresh_dc_cache(self):
 315         update = {
 316             'dc_slug': None,
 317         }
 318
 319         info = self.book_info()
 320         if info is not None:
 321             update['dc_slug'] = info.slug
 322         Book.objects.filter(pk=self.pk).update(**update)
 323
 324     def touch(self):
 325         # this should only really be done when text or publishable status changes
 326         book_content_updated.delay(self)
 327
 328         update = {
 329             "_new_publishable": self.is_new_publishable(),
 330             "_published": self.is_published(),
 331             "_single": self.is_single(),
 332             "_on_track": self.get_on_track(),
 333             "_short_html": None,
 334         }
 335         Book.objects.filter(pk=self.pk).update(**update)
 336         refresh_instance(self)
 337
 338     def refresh(self):
 339         """This should be done offline."""
 340         self.short_html
 341         self.single
 342         self.new_publishable
 343         self.published
 344
 345     # Materializing & publishing
 346     # ==========================
 347
 348     def get_current_changes(self, publishable=True):
 349         """
 350             Returns a list containing one Change for every Chunk in the Book.
 351             Takes the most recent revision (publishable, if set).
 352             Throws an error, if a proper revision is unavailable for a Chunk.
 353         """
 354         if publishable:
 355             changes = [chunk.publishable() for chunk in self]
 356         else:
 357             changes = [chunk.head for chunk in self if chunk.head is not None]
 358         if None in changes:
 359             raise self.NoTextError('Some chunks have no available text.')
 360         return changes
 361
 362     def materialize(self, publishable=False, changes=None):
 363         """
 364             Get full text of the document compiled from chunks.
 365             Takes the current versions of all texts
 366             or versions most recently tagged for publishing,
 367             or a specified iterable changes.
 368         """
 369         if changes is None:
 370             changes = self.get_current_changes(publishable)
 371         return compile_text(change.materialize() for change in changes)
 372
 373     def publish(self, user):
 374         """
 375             Publishes a book on behalf of a (local) user.
 376         """
 377         self.assert_publishable()
 378         changes = self.get_current_changes(publishable=True)
 379         book_xml = self.materialize(changes=changes)
 380         apiclient.api_call(user, "books/", {"book_xml": book_xml})
 381         # record the publish
 382         br = BookPublishRecord.objects.create(book=self, user=user)
 383         for c in changes:
 384             ChunkPublishRecord.objects.create(book_record=br, change=c)
 385         post_publish.send(sender=br)