django1/django/contrib/syndication/feeds.py

180 lines
7.2 KiB
Python

from datetime import datetime, timedelta
from django.core.exceptions import ImproperlyConfigured, ObjectDoesNotExist
from django.template import loader, Template, TemplateDoesNotExist
from django.contrib.sites.models import Site, RequestSite
from django.utils import feedgenerator
from django.utils.tzinfo import FixedOffset
from django.utils.encoding import smart_unicode, iri_to_uri
from django.conf import settings
from django.template import RequestContext
def add_domain(domain, url):
if not (url.startswith('http://') or url.startswith('https://')):
# 'url' must already be ASCII and URL-quoted, so no need for encoding
# conversions here.
url = iri_to_uri(u'http://%s%s' % (domain, url))
return url
class FeedDoesNotExist(ObjectDoesNotExist):
pass
class Feed(object):
item_pubdate = None
item_enclosure_url = None
feed_type = feedgenerator.DefaultFeed
feed_url = None
title_template = None
description_template = None
def __init__(self, slug, request):
self.slug = slug
self.request = request
self.feed_url = self.feed_url or request.path
self.title_template_name = self.title_template or ('feeds/%s_title.html' % slug)
self.description_template_name = self.description_template or ('feeds/%s_description.html' % slug)
def item_link(self, item):
try:
return item.get_absolute_url()
except AttributeError:
raise ImproperlyConfigured, "Give your %s class a get_absolute_url() method, or define an item_link() method in your Feed class." % item.__class__.__name__
def __get_dynamic_attr(self, attname, obj, default=None):
try:
attr = getattr(self, attname)
except AttributeError:
return default
if callable(attr):
# Check func_code.co_argcount rather than try/excepting the
# function and catching the TypeError, because something inside
# the function may raise the TypeError. This technique is more
# accurate.
if hasattr(attr, 'func_code'):
argcount = attr.func_code.co_argcount
else:
argcount = attr.__call__.func_code.co_argcount
if argcount == 2: # one argument is 'self'
return attr(obj)
else:
return attr()
return attr
def feed_extra_kwargs(self, obj):
"""
Returns an extra keyword arguments dictionary that is used when
initializing the feed generator.
"""
return {}
def item_extra_kwargs(self, item):
"""
Returns an extra keyword arguments dictionary that is used with
the `add_item` call of the feed generator.
"""
return {}
def get_object(self, bits):
return None
def get_feed(self, url=None):
"""
Returns a feedgenerator.DefaultFeed object, fully populated, for
this feed. Raises FeedDoesNotExist for invalid parameters.
"""
if url:
bits = url.split('/')
else:
bits = []
try:
obj = self.get_object(bits)
except ObjectDoesNotExist:
raise FeedDoesNotExist
if Site._meta.installed:
current_site = Site.objects.get_current()
else:
current_site = RequestSite(self.request)
link = self.__get_dynamic_attr('link', obj)
link = add_domain(current_site.domain, link)
feed = self.feed_type(
title = self.__get_dynamic_attr('title', obj),
subtitle = self.__get_dynamic_attr('subtitle', obj),
link = link,
description = self.__get_dynamic_attr('description', obj),
language = settings.LANGUAGE_CODE.decode(),
feed_url = add_domain(current_site.domain,
self.__get_dynamic_attr('feed_url', obj)),
author_name = self.__get_dynamic_attr('author_name', obj),
author_link = self.__get_dynamic_attr('author_link', obj),
author_email = self.__get_dynamic_attr('author_email', obj),
categories = self.__get_dynamic_attr('categories', obj),
feed_copyright = self.__get_dynamic_attr('feed_copyright', obj),
feed_guid = self.__get_dynamic_attr('feed_guid', obj),
ttl = self.__get_dynamic_attr('ttl', obj),
**self.feed_extra_kwargs(obj)
)
try:
title_tmp = loader.get_template(self.title_template_name)
except TemplateDoesNotExist:
title_tmp = Template('{{ obj }}')
try:
description_tmp = loader.get_template(self.description_template_name)
except TemplateDoesNotExist:
description_tmp = Template('{{ obj }}')
for item in self.__get_dynamic_attr('items', obj):
link = add_domain(current_site.domain, self.__get_dynamic_attr('item_link', item))
enc = None
enc_url = self.__get_dynamic_attr('item_enclosure_url', item)
if enc_url:
enc = feedgenerator.Enclosure(
url = smart_unicode(enc_url),
length = smart_unicode(self.__get_dynamic_attr('item_enclosure_length', item)),
mime_type = smart_unicode(self.__get_dynamic_attr('item_enclosure_mime_type', item))
)
author_name = self.__get_dynamic_attr('item_author_name', item)
if author_name is not None:
author_email = self.__get_dynamic_attr('item_author_email', item)
author_link = self.__get_dynamic_attr('item_author_link', item)
else:
author_email = author_link = None
pubdate = self.__get_dynamic_attr('item_pubdate', item)
if pubdate:
now = datetime.now()
utcnow = datetime.utcnow()
# Must always subtract smaller time from larger time here.
if utcnow > now:
sign = -1
tzDifference = (utcnow - now)
else:
sign = 1
tzDifference = (now - utcnow)
# Round the timezone offset to the nearest half hour.
tzOffsetMinutes = sign * ((tzDifference.seconds / 60 + 15) / 30) * 30
tzOffset = timedelta(minutes=tzOffsetMinutes)
pubdate = pubdate.replace(tzinfo=FixedOffset(tzOffset))
feed.add_item(
title = title_tmp.render(RequestContext(self.request, {'obj': item, 'site': current_site})),
link = link,
description = description_tmp.render(RequestContext(self.request, {'obj': item, 'site': current_site})),
unique_id = self.__get_dynamic_attr('item_guid', item, link),
enclosure = enc,
pubdate = pubdate,
author_name = author_name,
author_email = author_email,
author_link = author_link,
categories = self.__get_dynamic_attr('item_categories', item),
item_copyright = self.__get_dynamic_attr('item_copyright', item),
**self.item_extra_kwargs(item)
)
return feed