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
 213     # State & cache
 214     # =============
 215
 216     def last_published(self):
 217         try:
 218             return self.publish_log.all()[0].timestamp
 219         except IndexError:
 220             return None
 221
 222     def assert_publishable(self):
 223         assert self.chunk_set.exists(), _('No chunks in the book.')
 224         try:
 225             changes = self.get_current_changes(publishable=True)
 226         except self.NoTextError:
 227             raise AssertionError(_('Not all chunks have publishable revisions.'))
 228         book_xml = self.materialize(changes=changes)
 229
 230         from librarian.dcparser import BookInfo
 231         from librarian import NoDublinCore, ParseError, ValidationError
 232
 233         try:
 234             bi = BookInfo.from_string(book_xml.encode('utf-8'))
 235         except ParseError, e:
 236             raise AssertionError(_('Invalid XML') + ': ' + str(e))
 237         except NoDublinCore:
 238             raise AssertionError(_('No Dublin Core found.'))
 239         except ValidationError, e:
 240             raise AssertionError(_('Invalid Dublin Core') + ': ' + str(e))
 241
 242         valid_about = self.correct_about()
 243         assert bi.about == valid_about, _("rdf:about is not") + " " + valid_about
 244
 245     def hidden(self):
 246         return self.slug.startswith('.')
 247
 248     def is_new_publishable(self):
 249         """Checks if book is ready for publishing.
 250
 251         Returns True if there is a publishable version newer than the one
 252         already published.
 253
 254         """
 255         new_publishable = False
 256         if not self.chunk_set.exists():
 257             return False
 258         for chunk in self:
 259             change = chunk.publishable()
 260             if not change:
 261                 return False
 262             if not new_publishable and not change.publish_log.exists():
 263                 new_publishable = True
 264         return new_publishable
 265     new_publishable = cached_in_field('_new_publishable')(is_new_publishable)
 266
 267     def is_published(self):
 268         return self.publish_log.exists()
 269     published = cached_in_field('_published')(is_published)
 270
 271     def get_on_track(self):
 272         if self.published:
 273             return -1
 274         stages = [ch.stage.ordering for ch in self if ch.stage is not None]
 275         if not len(stages):
 276             return 0
 277         return min(stages)
 278     on_track = cached_in_field('_on_track')(get_on_track)
 279
 280     def is_single(self):
 281         return len(self) == 1
 282     single = cached_in_field('_single')(is_single)
 283
 284     @cached_in_field('_short_html')
 285     def short_html(self):
 286         return render_to_string('catalogue/book_list/book.html', {'book': self})
 287
 288     def book_info(self, publishable=True):
 289         try:
 290             book_xml = self.materialize(publishable=publishable)
 291         except self.NoTextError:
 292             pass
 293         else:
 294             from librarian.dcparser import BookInfo
 295             from librarian import NoDublinCore, ParseError, ValidationError
 296             try:
 297                 return BookInfo.from_string(book_xml.encode('utf-8'))
 298             except (self.NoTextError, ParseError, NoDublinCore, ValidationError):
 299                 return None
 300
 301     def refresh_dc_cache(self):
 302         update = {
 303             'dc_slug': None,
 304         }
 305
 306         info = self.book_info()
 307         if info is not None:
 308             update['dc_slug'] = info.slug
 309         Book.objects.filter(pk=self.pk).update(**update)
 310
 311     def touch(self):
 312         # this should only really be done when text or publishable status changes
 313         book_content_updated.delay(self)
 314
 315         update = {
 316             "_new_publishable": self.is_new_publishable(),
 317             "_published": self.is_published(),
 318             "_single": self.is_single(),
 319             "_on_track": self.get_on_track(),
 320             "_short_html": None,
 321         }
 322         Book.objects.filter(pk=self.pk).update(**update)
 323         refresh_instance(self)
 324
 325     def refresh(self):
 326         """This should be done offline."""
 327         self.short_html
 328         self.single
 329         self.new_publishable
 330         self.published
 331
 332     # Materializing & publishing
 333     # ==========================
 334
 335     def get_current_changes(self, publishable=True):
 336         """
 337             Returns a list containing one Change for every Chunk in the Book.
 338             Takes the most recent revision (publishable, if set).
 339             Throws an error, if a proper revision is unavailable for a Chunk.
 340         """
 341         if publishable:
 342             changes = [chunk.publishable() for chunk in self]
 343         else:
 344             changes = [chunk.head for chunk in self if chunk.head is not None]
 345         if None in changes:
 346             raise self.NoTextError('Some chunks have no available text.')
 347         return changes
 348
 349     def materialize(self, publishable=False, changes=None):
 350         """
 351             Get full text of the document compiled from chunks.
 352             Takes the current versions of all texts
 353             or versions most recently tagged for publishing,
 354             or a specified iterable changes.
 355         """
 356         if changes is None:
 357             changes = self.get_current_changes(publishable)
 358         return compile_text(change.materialize() for change in changes)
 359
 360     def publish(self, user):
 361         """
 362             Publishes a book on behalf of a (local) user.
 363         """
 364         self.assert_publishable()
 365         changes = self.get_current_changes(publishable=True)
 366         book_xml = self.materialize(changes=changes)
 367         apiclient.api_call(user, "books/", {"book_xml": book_xml})
 368         # record the publish
 369         br = BookPublishRecord.objects.create(book=self, user=user)
 370         for c in changes:
 371             ChunkPublishRecord.objects.create(book_record=br, change=c)
 372         post_publish.send(sender=br)