Add support for FB Instant Articles

djangocms_blog/feeds.py

@@ -1,19 +1,27 @@
 # -*- coding: utf-8 -*-
 from __future__ import absolute_import, print_function, unicode_literals
 
+from django.core.cache import cache
+from django.utils.encoding import force_text
+from django.utils.feedgenerator import Rss201rev2Feed, rfc2822_date
+
 from aldryn_apphooks_config.utils import get_app_instance
 from django.contrib.sites.models import Site
 from django.contrib.syndication.views import Feed
 from django.core.urlresolvers import reverse
-from django.utils.translation import ugettext as _
+from django.utils.safestring import mark_safe
+from django.utils.translation import ugettext as _, get_language_from_request
 
+from djangocms_blog.settings import get_setting
+from djangocms_blog.views import PostDetailView
 from .models import Post
-from .settings import get_setting
 
 
 class LatestEntriesFeed(Feed):
+    feed_type = Rss201rev2Feed
 
     def __call__(self, request, *args, **kwargs):
+        self.request = request
         self.namespace, self.config = get_app_instance(request)
         return super(LatestEntriesFeed, self).__call__(request, *args, **kwargs)
 
@@ -30,7 +38,7 @@ class LatestEntriesFeed(Feed):
         return item.safe_translation_getter('title')
 
     def item_description(self, item):
-        if get_setting('USE_ABSTRACT'):
+        if item.app_config.use_abstract:
             return item.safe_translation_getter('abstract')
         return item.safe_translation_getter('post_text')
 
@@ -42,3 +50,55 @@ class TagFeed(LatestEntriesFeed):
 
     def items(self, obj=None):
         return Post.objects.published().filter(tags__slug=obj)[:10]
+
+
+class FBInstantFeed(Rss201rev2Feed):
+
+    def rss_attributes(self):
+        return {
+            'version': self._version,
+            'xmlns:content': 'http://purl.org/rss/1.0/modules/content/'
+        }
+
+    def add_root_elements(self, handler):
+        handler.addQuickElement("title", self.feed['title'])
+        handler.addQuickElement("link", self.feed['link'])
+        handler.addQuickElement("description", self.feed['description'])
+        if self.feed['language'] is not None:
+            handler.addQuickElement("language", self.feed['language'])
+        for cat in self.feed['categories']:
+            handler.addQuickElement("category", cat)
+        if self.feed['feed_copyright'] is not None:
+            handler.addQuickElement("copyright", self.feed['feed_copyright'])
+        handler.addQuickElement("lastBuildDate", rfc2822_date(self.latest_post_date()))
+        if self.feed['ttl'] is not None:
+            handler.addQuickElement("ttl", self.feed['ttl'])
+
+    def add_item_elements(self, handler, item):
+        super(FBInstantFeed, self).add_item_elements(handler, item)
+        handler.startElement('content:encoded', {})
+        handler._write('<![CDATA[')
+        handler._write(force_text(item['content']))
+        handler._write(']]>')
+        handler.endElement('content:encoded')
+
+
+class FBInstantArticles(LatestEntriesFeed):
+    feed_type = FBInstantFeed
+
+    def item_extra_kwargs(self, item):
+        if not item:
+            return {}
+        language = get_language_from_request(self.request, check_path=True)
+        key = item.get_cache_key(language, 'feed')
+        content = cache.get(key)
+        if not content:
+            view = PostDetailView.as_view(instant_article=True)
+            response = view(self.request, slug=item.safe_translation_getter('slug'))
+            response.render()
+            content = mark_safe(response.content)
+            cache.set(key, content, timeout=get_setting('FEED_CACHE_TIMEOUT'))
+        return {
+            'content': content,
+            'slug': item.safe_translation_getter('slug'),
+        }

djangocms_blog/models.py

@@ -1,13 +1,18 @@
 # -*- coding: utf-8 -*-
 from __future__ import absolute_import, print_function, unicode_literals
 
+import hashlib
+
 from aldryn_apphooks_config.fields import AppHookConfigField
 from aldryn_apphooks_config.managers.parler import AppHookConfigTranslatableManager
 from cms.models import CMSPlugin, PlaceholderField
 from django.conf import settings as dj_settings
 from django.contrib.auth import get_user_model
+from django.core.cache import cache
 from django.core.urlresolvers import reverse
 from django.db import models
+from django.db.models.signals import post_save, pre_delete
+from django.dispatch import receiver
 from django.utils import timezone
 from django.utils.encoding import force_text, python_2_unicode_compatible
 from django.utils.html import escape, strip_tags
@@ -196,6 +201,12 @@ class Post(KnockerModel, ModelMeta, TranslatableModel):
     def __str__(self):
         return self.safe_translation_getter('title')
 
+    @property
+    def guid(self, language=None):
+        if not language:
+            language = self.get_current_language()
+        return hashlib.sha256(self.get_absolute_url(language)).hexdigest()
+
     def save(self, *args, **kwargs):
         """
         Handle some auto configuration during save
@@ -329,6 +340,9 @@ class Post(KnockerModel, ModelMeta, TranslatableModel):
         updated = self.app_config.send_knock_update and self.is_published
         return new or updated
 
+    def get_cache_key(self, language, prefix):
+        return 'djangocms-blog:{2}:{0}:{1}'.format(language, self.guid, prefix)
+
 
 class BasePostPlugin(CMSPlugin):
     app_config = AppHookConfigField(
@@ -422,3 +436,17 @@ class GenericBlogPlugin(BasePostPlugin):
 
     def __str__(self):
         return force_text(_('generic blog plugin'))
+
+
+@receiver(pre_delete, sender=Post)
+def cleanup_post(sender, instance, **kwargs):
+    for language in instance.get_available_languages():
+        key = instance.get_cache_key(language, 'feed')
+        cache.delete(key)
+
+
+@receiver(post_save, sender=Post)
+def cleanup_pagemeta(sender, instance, **kwargs):
+    for language in instance.get_available_languages():
+        key = instance.get_cache_key(language, 'feed')
+        cache.delete(key)

djangocms_blog/settings.py

@@ -1,6 +1,8 @@
 # -*- coding: utf-8 -*-
 from __future__ import absolute_import, print_function, unicode_literals
 
+from django.utils.safestring import mark_safe
+
 MENU_TYPE_COMPLETE = 'complete'
 MENU_TYPE_CATEGORIES = 'categories'
 MENU_TYPE_POSTS = 'posts'
@@ -121,6 +123,8 @@ def get_setting(name):
             settings, 'BLOG_CATEGORY_PLUGIN_NAME', _('Categories')),
         'BLOG_ARCHIVE_PLUGIN_NAME': getattr(
             settings, 'BLOG_ARCHIVE_PLUGIN_NAME', _('Archive')),
+        'BLOG_FEED_CACHE_TIMEOUT': getattr(
+            settings, 'BLOG_FEED_CACHE_TIMEOUT', 3600),
 
     }
     return default['BLOG_%s' % name]

djangocms_blog/templates/djangocms_blog/includes/blog_meta.html

@@ -23,4 +23,4 @@
             <li class="tag_{{ forloop.counter }}"><a href="{% url 'djangocms_blog:posts-tagged' tag=tag.slug %}" class="blog-tag blog-tag-{{ tag.count }}">{{ tag.name }}</a>{% if not forloop.last %}, {% endif %}</li>
         {% endfor %}
     {% endif %}
-</ul>
+</ul>

djangocms_blog/templates/djangocms_blog/post_instant_article.html

@@ -0,0 +1,44 @@
+{% load thumbnail cms_tags %}
+<!doctype html>
+<html lang="en" prefix="op: http://media.facebook.com/op#">
+  <head>
+      <meta charset="utf-8">
+      {% block canonical_url %}<link rel="canonical" href="{{ meta.url }}"/>{% endblock canonical_url %}
+      <meta property="op:markup_version" content="v1.0">
+  </head>
+  <body>
+    <article>
+      <header>
+        <h1>{{ post.title }}</h1>
+
+        <time class="op-published" datetime="{{ post.date_published.isoformat }}">{{ post.date_published|date:"DATE_FORMAT" }}</time>
+
+        <time class="op-modified" dateTime="{{ post.date_modified.isoformat }}">{{ post.date_modified|date:"DATE_FORMAT" }}</time>
+
+        <address>
+            {% if og_author_url %}<a rel="facebook" href="{{ og_author_url }}">{% endif %}
+            {{ post.author }}
+            {% if og_author_url %}</a>{% endif %}
+        </address>
+
+        <figure>
+            <img src="{{ meta.image }}" alt="{{ post.main_image.default_alt_text }}" />
+            {% if post.main_image.default_caption %}
+                <figcaption>{{ post.main_image.default_caption }}</figcaption>{% endif %}
+        </figure>
+
+        <h3 class="op-kicker">
+          {{ post.abstract|striptags }}
+        </h3>
+
+      </header>
+
+        {% if post.app_config.use_placeholder %}
+            <div class="blog-content">{% render_placeholder post.content %}</div>
+        {% else %}
+            <div class="blog-content">{% render_model post "post_text" "post_text" %}</div>
+        {% endif %}
+
+    </article>
+  </body>
+</html>

djangocms_blog/urls.py

@@ -3,7 +3,7 @@ from __future__ import absolute_import, print_function, unicode_literals
 
 from django.conf.urls import url
 
-from .feeds import LatestEntriesFeed, TagFeed
+from .feeds import FBInstantArticles, LatestEntriesFeed, TagFeed
 from .settings import get_setting
 from .views import (
     AuthorEntriesView, CategoryEntriesView, PostArchiveView, PostDetailView, PostListView,
@@ -27,6 +27,8 @@ urlpatterns = [
         PostListView.as_view(), name='posts-latest'),
     url(r'^feed/$',
         LatestEntriesFeed(), name='posts-latest-feed'),
+    url(r'^feed/fb/$',
+        FBInstantArticles(), name='posts-latest-feed-fb'),
     url(r'^(?P<year>\d{4})/$',
         PostArchiveView.as_view(), name='posts-archive'),
     url(r'^(?P<year>\d{4})/(?P<month>\d{1,2})/$',

djangocms_blog/views.py

@@ -72,6 +72,14 @@ class PostDetailView(TranslatableSlugMixin, BaseBlogView, DetailView):
     base_template_name = 'post_detail.html'
     slug_field = 'slug'
     view_url_name = 'djangocms_blog:post-detail'
+    instant_article = False
+
+    def get_template_names(self):
+        if self.instant_article:
+            template_path = (self.config and self.config.template_prefix) or 'djangocms_blog'
+            return os.path.join(template_path, 'post_instant_article.html')
+        else:
+            return super(PostDetailView, self).get_template_names()
 
     def get_queryset(self):
         queryset = self.model._default_manager.all()
@@ -88,6 +96,7 @@ class PostDetailView(TranslatableSlugMixin, BaseBlogView, DetailView):
     def get_context_data(self, **kwargs):
         context = super(PostDetailView, self).get_context_data(**kwargs)
         context['meta'] = self.get_object().as_meta()
+        context['instant_article'] = self.instant_article
         context['use_placeholder'] = get_setting('USE_PLACEHOLDER')
         setattr(self.request, get_setting('CURRENT_POST_IDENTIFIER'), self.get_object())
         return context