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