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