apps/catalogue/feeds.py

   1 # -*- coding: utf-8 -*-
   2 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
   3 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
   4 #
   5 from base64 import b64encode
   6 import os.path
   7
   8 from django.contrib.syndication.views import Feed
   9 from django.core.urlresolvers import reverse
  10 from django.shortcuts import get_object_or_404
  11 from django.utils.feedgenerator import Atom1Feed
  12 from django.conf import settings
  13 from django.http import Http404
  14 from django.contrib.sites.models import Site
  15
  16 from catalogue.models import Book, Tag
  17
  18
  19 _root_feeds = (
  20        {u"category": u"author", u"title": u"Autorzy", u"description": u"Utwory wg autorów"},
  21        {u"category": u"kind", u"title": u"Rodzaje", u"description": u"Utwory wg rodzajów"},
  22        {u"category": u"genre", u"title": u"Gatunki", u"description": u"Utwory wg gatunków"},
  23        {u"category": u"epoch", u"title": u"Epoki", u"description": u"Utwory wg epok"},
  24 )
  25
  26
  27 class OPDSFeed(Atom1Feed):
  28     link_rel = u"subsection"
  29     link_type = u"application/atom+xml"
  30
  31     try:
  32         with open(os.path.join(settings.STATIC_ROOT, "img/book-par ent.png")) as f:
  33             t = f.read()
  34             _book_parent_img_size = len(t)
  35             _book_parent_img = b64encode(t)
  36     except:
  37         _book_parent_img = _book_parent_img_size = ''
  38
  39     try:
  40         with open(os.path.join(settings.STATIC_ROOT, "img/bo ok.png")) as f:
  41             t = f.read()
  42             _book_img_size = len(t)
  43             _book_img = b64encode(t)
  44     except:
  45         _book_img = _book_img_size = ''
  46
  47     def add_root_elements(self, handler):
  48         super(OPDSFeed, self).add_root_elements(handler)
  49         handler.addQuickElement(u"link", u"", {u"href": reverse("opds_authors"), u"rel": u"start", u"type": u"application/atom+xml"})
  50
  51
  52     def add_item_elements(self, handler, item):
  53         """ modified from Atom1Feed.add_item_elements """
  54         handler.addQuickElement(u"title", item['title'])
  55
  56         # add a OPDS Navigation link if there's no enclosure
  57         if item['enclosure'] is None:
  58             handler.addQuickElement(u"link", u"", {u"href": item['link'], u"rel": u"subsection", u"type": u"application/atom+xml"})
  59             # add a "green book" icon
  60             handler.addQuickElement(u"link", '',
  61                 {u"rel": u"http://opds-spec.org/thumbnail",
  62                  u"href": u"data:image/png;base64,%s" % self._book_parent_img,
  63                  u"length": unicode(self._book_parent_img_size),
  64                  u"type": u"image/png"})
  65         if item['pubdate'] is not None:
  66             handler.addQuickElement(u"updated", rfc3339_date(item['pubdate']).decode('utf-8'))
  67
  68         # Author information.
  69         if item['author_name'] is not None:
  70             handler.startElement(u"author", {})
  71             handler.addQuickElement(u"name", item['author_name'])
  72             if item['author_email'] is not None:
  73                 handler.addQuickElement(u"email", item['author_email'])
  74             if item['author_link'] is not None:
  75                 handler.addQuickElement(u"uri", item['author_link'])
  76             handler.endElement(u"author")
  77
  78         # Unique ID.
  79         if item['unique_id'] is not None:
  80             unique_id = item['unique_id']
  81         else:
  82             unique_id = get_tag_uri(item['link'], item['pubdate'])
  83         handler.addQuickElement(u"id", unique_id)
  84
  85         # Summary.
  86         # OPDS needs type=text
  87         if item['description'] is not None:
  88             handler.addQuickElement(u"summary", item['description'], {u"type": u"text"})
  89
  90         # Enclosure as OPDS Acquisition Link
  91         if item['enclosure'] is not None:
  92             handler.addQuickElement(u"link", '',
  93                 {u"rel": u"http://opds-spec.org/acquisition",
  94                  u"href": item['enclosure'].url,
  95                  u"length": item['enclosure'].length,
  96                  u"type": item['enclosure'].mime_type})
  97             # add a "red book" icon
  98             handler.addQuickElement(u"link", '',
  99                 {u"rel": u"http://opds-spec.org/thumbnail",
 100                  u"href": u"data:image/png;base64,%s" % self._book_img,
 101                  u"length": unicode(self._book_img_size),
 102                  u"type": u"image/png"})
 103
 104         # Categories.
 105         for cat in item['categories']:
 106             handler.addQuickElement(u"category", u"", {u"term": cat})
 107
 108         # Rights.
 109         if item['item_copyright'] is not None:
 110             handler.addQuickElement(u"rights", item['item_copyright'])
 111
 112
 113 class RootFeed(Feed):
 114     feed_type = OPDSFeed
 115     title = u'Wolne Lektury'
 116     link = u'http://www.wolnelektury.pl/'
 117     description = u"Spis utworów na stronie http://WolneLektury.pl"
 118     author_name = u"Wolne Lektury"
 119     author_link = u"http://www.wolnelektury.pl/"
 120
 121     def items(self):
 122         return _root_feeds
 123
 124     def item_title(self, item):
 125         return item['title']
 126
 127     def item_link(self, item):
 128         return reverse(u"opds_by_category", args=[item['category']])
 129
 130     def item_description(self, item):
 131         return item['description']
 132
 133
 134 class ByCategoryFeed(Feed):
 135     feed_type = OPDSFeed
 136     link = u'http://www.wolnelektury.pl/'
 137     description = u"Spis utworów na stronie http://WolneLektury.pl"
 138     author_name = u"Wolne Lektury"
 139     author_link = u"http://www.wolnelektury.pl/"
 140
 141     def get_object(self, request, category):
 142         feed = [feed for feed in _root_feeds if feed['category']==category]
 143         if feed:
 144             feed = feed[0]
 145         else:
 146             raise Http404
 147
 148         return feed
 149
 150     def title(self, feed):
 151         return feed['title']
 152
 153     def items(self, feed):
 154         return (tag for tag in Tag.objects.filter(category=feed['category']) if tag.get_count() > 0)
 155
 156     def item_title(self, item):
 157         return item.name
 158
 159     def item_link(self, item):
 160         return reverse("opds_by_tag", args=[item.category, item.slug])
 161
 162     def item_description(self):
 163         return u''
 164
 165
 166 class ByTagFeed(Feed):
 167     feed_type = OPDSFeed
 168     link = u'http://www.wolnelektury.pl/'
 169     item_enclosure_mime_type = "application/epub+zip"
 170     author_name = u"Wolne Lektury"
 171     author_link = u"http://www.wolnelektury.pl/"
 172
 173     def link(self, tag):
 174         return tag.get_absolute_url()
 175
 176     def title(self, tag):
 177         return tag.name
 178
 179     def description(self, tag):
 180         return u"Spis utworów na stronie http://WolneLektury.pl"
 181
 182     def get_object(self, request, category, slug):
 183         return get_object_or_404(Tag, category=category, slug=slug)
 184
 185     def items(self, tag):
 186         books = Book.tagged.with_any([tag])
 187         l_tags = Tag.objects.filter(category='book', slug__in=[book.book_tag_slug() for book in books])
 188         descendants_keys = [book.pk for book in Book.tagged.with_any(l_tags)]
 189         if descendants_keys:
 190             books = books.exclude(pk__in=descendants_keys)
 191
 192         return books
 193
 194     def item_title(self, book):
 195         return book.title
 196
 197     def item_description(self):
 198         return u''
 199
 200     def item_link(self, book):
 201         return book.get_absolute_url()
 202
 203     def item_author_name(self, book):
 204         try:
 205             return book.tags.filter(category='author')[0].name
 206         except KeyError:
 207             return u''
 208
 209     def item_author_link(self, book):
 210         try:
 211             return book.tags.filter(category='author')[0].get_absolute_url()
 212         except KeyError:
 213             return u''
 214
 215     def item_enclosure_url(self, book):
 216         return "http://%s%s" % (Site.objects.get_current().domain, book.epub_file.url)
 217
 218     def item_enclosure_length(self, book):
 219         return book.epub_file.size