apps/catalogue/models/image.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.conf import settings
   7 from django.contrib.sites.models import Site
   8 from django.db import models
   9 from django.template.loader import render_to_string
  10 from django.utils.translation import ugettext_lazy as _
  11 from catalogue.helpers import cached_in_field
  12 from catalogue.models import Project
  13 from catalogue.tasks import refresh_instance
  14 from dvcs import models as dvcs_models
  15
  16
  17 class Image(dvcs_models.Document):
  18     """ An editable chunk of text. Every Book text is divided into chunks. """
  19     REPO_PATH = settings.CATALOGUE_IMAGE_REPO_PATH
  20
  21     image = models.FileField(_('image'), upload_to='catalogue/images')
  22     title = models.CharField(_('title'), max_length=255, blank=True)
  23     slug = models.SlugField(_('slug'), unique=True)
  24     public = models.BooleanField(_('public'), default=True, db_index=True)
  25     project = models.ForeignKey(Project, null=True, blank=True)
  26
  27     # cache
  28     _short_html = models.TextField(null=True, blank=True, editable=False)
  29     _new_publishable = models.NullBooleanField(editable=False)
  30     _published = models.NullBooleanField(editable=False)
  31     _changed = models.NullBooleanField(editable=False)
  32
  33     class Meta:
  34         app_label = 'catalogue'
  35         ordering = ['title']
  36         verbose_name = _('image')
  37         verbose_name_plural = _('images')
  38         permissions = [('can_pubmark_image', 'Can mark images for publishing')]
  39
  40     # Representing
  41     # ============
  42
  43     def __unicode__(self):
  44         return self.title
  45
  46     @models.permalink
  47     def get_absolute_url(self):
  48         return ("catalogue_image", [self.slug])
  49
  50     def correct_about(self):
  51         return "http://%s%s" % (
  52             Site.objects.get_current().domain,
  53             self.get_absolute_url()
  54         )
  55
  56     # State & cache
  57     # =============
  58
  59     def last_published(self):
  60         try:
  61             return self.publish_log.all()[0].timestamp
  62         except IndexError:
  63             return None
  64
  65     def assert_publishable(self):
  66         from librarian.picture import WLPicture
  67         from librarian import NoDublinCore, ParseError, ValidationError
  68
  69         class SelfImageStore(object):
  70             def path(self_, slug, mime_type):
  71                 """Returns own file object. Ignores slug ad mime_type."""
  72                 return open(self.image.path)
  73
  74         publishable = self.publishable()
  75         assert publishable, _("There is no publishable revision")
  76         picture_xml = publishable.materialize()
  77
  78         try:
  79             picture = WLPicture.from_string(picture_xml.encode('utf-8'),
  80                     image_store=SelfImageStore)
  81         except ParseError, e:
  82             raise AssertionError(_('Invalid XML') + ': ' + str(e))
  83         except NoDublinCore:
  84             raise AssertionError(_('No Dublin Core found.'))
  85         except ValidationError, e:
  86             raise AssertionError(_('Invalid Dublin Core') + ': ' + str(e))
  87
  88         valid_about = self.correct_about()
  89         assert picture.picture_info.about == valid_about, \
  90                 _("rdf:about is not") + " " + valid_about
  91
  92     def publishable_error(self):
  93         try:
  94             return self.assert_publishable()
  95         except AssertionError, e:
  96             return e
  97         else:
  98             return None
  99
 100     def accessible(self, request):
 101         return self.public or request.user.is_authenticated()
 102
 103     def is_new_publishable(self):
 104         change = self.publishable()
 105         if not change:
 106             return False
 107         return not change.publish_log.exists()
 108     new_publishable = cached_in_field('_new_publishable')(is_new_publishable)
 109
 110     def is_published(self):
 111         return self.publish_log.exists()
 112     published = cached_in_field('_published')(is_published)
 113
 114     def is_changed(self):
 115         if self.head is None:
 116             return False
 117         return not self.head.publishable
 118     changed = cached_in_field('_changed')(is_changed)
 119
 120     @cached_in_field('_short_html')
 121     def short_html(self):
 122         return render_to_string(
 123                     'catalogue/image_short.html', {'image': self})
 124
 125     def refresh(self):
 126         """This should be done offline."""
 127         self.short_html
 128         self.single
 129         self.new_publishable
 130         self.published
 131
 132     def touch(self):
 133         update = {
 134             "_changed": self.is_changed(),
 135             "_short_html": None,
 136             "_new_publishable": self.is_new_publishable(),
 137             "_published": self.is_published(),
 138         }
 139         Image.objects.filter(pk=self.pk).update(**update)
 140         refresh_instance(self)
 141
 142     def refresh(self):
 143         """This should be done offline."""
 144         self.changed
 145         self.short_html
 146
 147
 148     # Publishing
 149     # ==========
 150
 151     def publish(self, user):
 152         """Publishes the picture on behalf of a (local) user."""
 153         from base64 import b64encode
 154         import apiclient
 155         from catalogue.signals import post_publish
 156
 157         self.assert_publishable()
 158         change = self.publishable()
 159         picture_xml = change.materialize()
 160         picture_data = open(self.image.path).read()
 161         apiclient.api_call(user, "pictures/", {
 162                 "picture_xml": picture_xml,
 163                 "picture_image_data": b64encode(picture_data),
 164             })
 165         # record the publish
 166         log = self.publish_log.create(user=user, change=change)
 167         post_publish.send(sender=log)