support networkpath reference see 16753 rss requires a protocol if itempubdate or itemupdateddate is defined for the feed set header so as conditionalgetmiddleware is able to send 304 not modified titles should be double escaped by default see 6533 check coargcount rather than tryexcepting the function and catching the typeerror because something inside the function may raise the typeerror this technique is more accurate if function doesn t have arguments and it is not a static method it was decorated without using functools wraps return an extra keyword arguments dictionary that is used when initializing the feed generator return an extra keyword arguments dictionary that is used with the additem call of the feed generator return a dictionary to use as extra context if either self descriptiontemplate or self itemtemplate are used default implementation preserves the old behavior of using obj item site currentsite as the context return a feedgenerator defaultfeed object fully populated for this feed raise feeddoesnotexist for invalid parameters support network path reference see 16753 rss requires a protocol if item_pubdate or item_updateddate is defined for the feed set header so as conditionalgetmiddleware is able to send 304 not modified titles should be double escaped by default see 6533 check 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 function doesn t have arguments and it is not a static method it was decorated without using functools wraps one argument is self return an extra keyword arguments dictionary that is used when initializing the feed generator return an extra keyword arguments dictionary that is used with the add_item call of the feed generator return a dictionary to use as extra context if either self description_template or self item_template are used default implementation preserves the old behavior of using obj item site current_site as the context return a feedgenerator defaultfeed object fully populated for this feed raise feeddoesnotexist for invalid parameters
from inspect import getattr_static, unwrap

from django.contrib.sites.shortcuts import get_current_site
from django.core.exceptions import ImproperlyConfigured, ObjectDoesNotExist
from django.http import Http404, HttpResponse
from django.template import TemplateDoesNotExist, loader
from django.utils import feedgenerator
from django.utils.encoding import iri_to_uri
from django.utils.html import escape
from django.utils.http import http_date
from django.utils.timezone import get_default_timezone, is_naive, make_aware
from django.utils.translation import get_language


def add_domain(domain, url, secure=False):
    protocol = "https" if secure else "http"
    if url.startswith("//"):
        
        url = "%s:%s" % (protocol, url)
    elif not url.startswith(("http://", "https://", "mailto:")):
        url = iri_to_uri("%s://%s%s" % (protocol, domain, url))
    return url


class FeedDoesNotExist(ObjectDoesNotExist):
    pass


class Feed:
    feed_type = feedgenerator.DefaultFeed
    title_template = None
    description_template = None
    language = None

    def __call__(self, request, *args, **kwargs):
        try:
            obj = self.get_object(request, *args, **kwargs)
        except ObjectDoesNotExist:
            raise Http404("Feed object does not exist.")
        feedgen = self.get_feed(obj, request)
        response = HttpResponse(content_type=feedgen.content_type)
        if hasattr(self, "item_pubdate") or hasattr(self, "item_updateddate"):
            
            
            response.headers["Last-Modified"] = http_date(
                feedgen.latest_post_date().timestamp()
            )
        feedgen.write(response, "utf-8")
        return response

    def item_title(self, item):
        
        return escape(str(item))

    def item_description(self, item):
        return str(item)

    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 item_enclosures(self, item):
        enc_url = self._get_dynamic_attr("item_enclosure_url", item)
        if enc_url:
            enc = feedgenerator.Enclosure(
                url=str(enc_url),
                length=str(self._get_dynamic_attr("item_enclosure_length", item)),
                mime_type=str(self._get_dynamic_attr("item_enclosure_mime_type", item)),
            )
            return [enc]
        return []

    def _get_dynamic_attr(self, attname, obj, default=None):
        try:
            attr = getattr(self, attname)
        except AttributeError:
            return default
        if callable(attr):
            
            
            
            func = unwrap(attr)
            try:
                code = func.__code__
            except AttributeError:
                func = unwrap(attr.__call__)
                code = func.__code__
            
            
            if not code.co_argcount and not isinstance(
                getattr_static(self, func.__name__, None), staticmethod
            ):
                raise ImproperlyConfigured(
                    f"Feed method {attname!r} decorated by {func.__name__!r} needs to "
                    f"use @functools.wraps."
                )
            if code.co_argcount == 2:  
                return attr(obj)
            else:
                return attr()
        return attr

    def feed_extra_kwargs(self, obj):
        
        return {}

    def item_extra_kwargs(self, item):
        
        return {}

    def get_object(self, request, *args, **kwargs):
        return None

    def get_context_data(self, **kwargs):
        
        return {"obj": kwargs.get("item"), "site": kwargs.get("site")}

    def get_feed(self, obj, request):
        
        current_site = get_current_site(request)

        link = self._get_dynamic_attr("link", obj)
        link = add_domain(current_site.domain, link, request.is_secure())

        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=self.language or get_language(),
            feed_url=add_domain(
                current_site.domain,
                self._get_dynamic_attr("feed_url", obj) or request.path,
                request.is_secure(),
            ),
            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),
        )

        title_tmp = None
        if self.title_template is not None:
            try:
                title_tmp = loader.get_template(self.title_template)
            except TemplateDoesNotExist:
                pass

        description_tmp = None
        if self.description_template is not None:
            try:
                description_tmp = loader.get_template(self.description_template)
            except TemplateDoesNotExist:
                pass

        for item in self._get_dynamic_attr("items", obj):
            context = self.get_context_data(
                item=item, site=current_site, obj=obj, request=request
            )
            if title_tmp is not None:
                title = title_tmp.render(context, request)
            else:
                title = self._get_dynamic_attr("item_title", item)
            if description_tmp is not None:
                description = description_tmp.render(context, request)
            else:
                description = self._get_dynamic_attr("item_description", item)
            link = add_domain(
                current_site.domain,
                self._get_dynamic_attr("item_link", item),
                request.is_secure(),
            )
            enclosures = self._get_dynamic_attr("item_enclosures", 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

            tz = get_default_timezone()

            pubdate = self._get_dynamic_attr("item_pubdate", item)
            if pubdate and is_naive(pubdate):
                pubdate = make_aware(pubdate, tz)

            updateddate = self._get_dynamic_attr("item_updateddate", item)
            if updateddate and is_naive(updateddate):
                updateddate = make_aware(updateddate, tz)

            feed.add_item(
                title=title,
                link=link,
                description=description,
                unique_id=self._get_dynamic_attr("item_guid", item, link),
                unique_id_is_permalink=self._get_dynamic_attr(
                    "item_guid_is_permalink", item
                ),
                enclosures=enclosures,
                pubdate=pubdate,
                updateddate=updateddate,
                author_name=author_name,
                author_email=author_email,
                author_link=author_link,
                comments=self._get_dynamic_attr("item_comments", item),
                categories=self._get_dynamic_attr("item_categories", item),
                item_copyright=self._get_dynamic_attr("item_copyright", item),
                **self.item_extra_kwargs(item),
            )
        return feed