"""Convert between ActivityStreams and RSS 2.0.
RSS 2.0 spec: http://www.rssboard.org/rss-specification
Apple iTunes Podcasts feed requirements:
https://help.apple.com/itc/podcasts_connect/#/itc1723472cb
Notably:
* Valid RSS 2.0.
* Each podcast item requires <guid>.
* Images should be JPEG or PNG, 1400x1400 to 3000x3000.
* HTTP server that hosts assets and files should support range requests.
"""
from datetime import datetime, time
import logging
import mimetypes
from feedgen.feed import FeedGenerator
import mf2util
from oauth_dropins.webutil import util
from . import microformats2
# allowed ActivityStreams objectTypes for media enclosures
ENCLOSURE_TYPES = {'audio', 'video'}
[docs]def from_activities(activities, actor=None, title=None, feed_url=None,
home_page_url=None, hfeed=None):
"""Converts ActivityStreams activities to an RSS 2.0 feed.
Args:
activities: sequence of ActivityStreams activity dicts
actor: ActivityStreams actor dict, the author of the feed
title: string, the feed title
feed_url: string, the URL for this RSS feed
home_page_url: string, the home page URL
hfeed: dict, parsed mf2 h-feed, if available
Returns:
unicode string with RSS 2.0 XML
"""
try:
iter(activities)
except TypeError:
raise TypeError('activities must be iterable')
if isinstance(activities, (dict, str)):
raise TypeError('activities may not be a dict or string')
fg = FeedGenerator()
fg.id(feed_url)
assert feed_url
fg.link(href=feed_url, rel='self')
if home_page_url:
fg.link(href=home_page_url, rel='alternate')
# TODO: parse language from lang attribute:
# https://github.com/microformats/mf2py/issues/150
fg.language('en')
fg.generator('granary', uri='https://granary.io/')
hfeed = hfeed or {}
actor = actor or {}
image = (util.get_url(hfeed.get('properties', {}), 'photo') or
util.get_url(actor, 'image'))
if image:
fg.image(image)
props = hfeed.get('properties') or {}
content = microformats2.get_text(util.get_first(props, 'content', ''))
summary = util.get_first(props, 'summary', '')
desc = content or summary or '-'
fg.description(desc) # required
fg.title(title or util.ellipsize(desc)) # required
latest = None
feed_has_enclosure = False
for activity in activities:
obj = activity.get('object') or activity
if obj.get('objectType') == 'person':
continue
item = fg.add_entry()
url = obj.get('url')
id = obj.get('id') or url
item.id(id)
item.link(href=url)
item.guid(url, permalink=True)
# title (required)
title = (obj.get('title') or obj.get('displayName') or
util.ellipsize(obj.get('content', '-')))
# strip HTML tags
title = util.parse_html(title).get_text('').strip()
item.title(title)
content = microformats2.render_content(
obj, include_location=True, render_attachments=True, render_image=True)
if not content:
content = obj.get('summary')
if content:
item.content(content, type='CDATA')
categories = [
{'term': t['displayName']} for t in obj.get('tags', [])
if t.get('displayName') and
t.get('verb') not in ('like', 'react', 'share') and
t.get('objectType') not in ('article', 'person', 'mention')]
item.category(categories)
author = obj.get('author', {})
author = {
'name': author.get('displayName') or author.get('username'),
'uri': author.get('url'),
'email': author.get('email') or '-',
}
item.author(author)
published = obj.get('published') or obj.get('updated')
if published and isinstance(published, str):
try:
dt = mf2util.parse_datetime(published)
if not isinstance(dt, datetime):
dt = datetime.combine(dt, time.min)
if not dt.tzinfo:
dt = dt.replace(tzinfo=util.UTC)
item.published(dt)
if not latest or dt > latest:
latest = dt
except ValueError: # bad datetime string
pass
item_has_enclosure = False
for att in obj.get('attachments', []):
stream = util.get_first(att, 'stream') or att
if not stream:
continue
url = stream.get('url') or ''
mime = mimetypes.guess_type(url)[0] or ''
if (att.get('objectType') in ENCLOSURE_TYPES or
mime and mime.split('/')[0] in ENCLOSURE_TYPES):
if item_has_enclosure:
logging.info('Warning: item %s already has an RSS enclosure, skipping additional enclosure %s',
id, url)
continue
item_has_enclosure = feed_has_enclosure = True
item.enclosure(url=url, type=mime, length=str(stream.get('size', '')))
item.load_extension('podcast')
duration = stream.get('duration')
if duration:
item.podcast.itunes_duration(duration)
if feed_has_enclosure:
fg.load_extension('podcast')
fg.podcast.itunes_author(actor.get('displayName') or actor.get('username'))
if summary:
fg.podcast.itunes_summary(summary)
fg.podcast.itunes_explicit('no')
fg.podcast.itunes_block(False)
name = author.get('name')
if name:
fg.podcast.itunes_author(name)
if image:
fg.podcast.itunes_image(image)
fg.podcast.itunes_category(categories)
if latest:
fg.lastBuildDate(latest)
return fg.rss_str(pretty=True).decode('utf-8')