Merge branch 'master' of git://github.com/melinath/philo
[philo.git] / contrib / penfield / utils.py
index e9415c0..43c7c91 100644 (file)
-from django.core.paginator import Paginator
+from django.utils.feedgenerator import Atom1Feed, Rss201rev2Feed
+from django.conf.urls.defaults import url, patterns
+from django.contrib.sites.models import Site
+from django.core.urlresolvers import reverse
+from django.http import HttpResponse
+from philo.utils import paginate
 
 
-class PaginationProxy(object):
-       def __init__(self, paginator=None, page=None, objects=None):
-               self.paginator = paginator
-               self.page = page
-               self.objects = objects
+class FeedMultiViewMixin(object):
+       """
+       This mixin provides common methods for adding feeds to multiviews. In order to use this mixin,
+       the multiview must define feed_title (probably as properties that return values
+       on related objects.) feed_description may also be defined; it defaults to an empty string.
+       """
+       feed_suffix = 'feed'
+       feeds_enabled = True
+       atom_feed = Atom1Feed
+       rss_feed = Rss201rev2Feed
+       feed_title = None
+       feed_description = None
+       list_var = 'objects'
        
-       @property
-       def page_range(self):
-               if not self.paginator:
-                       return None
-               
-               return self.paginator.page_range
+       def page_view(self, func, page):
+               """
+               Wraps an object-fetching function and renders the results as a page.
+               """
+               def inner(request, extra_context=None, **kwargs):
+                       objects, extra_context = func(request=request, extra_context=extra_context, **kwargs)
+
+                       context = self.get_context()
+                       context.update(extra_context or {})
+
+                       if 'page' in kwargs or 'page' in request.GET or (hasattr(self, 'per_page') and self.per_page):
+                               page_num = kwargs.get('page', request.GET.get('page', 1))
+                               paginator, paginated_page, objects = paginate(objects, self.per_page, page_num)
+                               context.update({'paginator': paginator, 'paginated_page': paginated_page, self.list_var: objects})
+                       else:
+                               context.update({self.list_var: objects})
+
+                       return page.render_to_response(request, extra_context=context)
+
+               return inner
        
-       @property
-       def num_pages(self):
-               if not self.paginator:
-                       return None
-               
-               return self.paginator.num_pages
+       def feed_view(self, func, reverse_name):
+               """
+               Wraps an object-fetching function and renders the results as a rss or atom feed.
+               """
+               def inner(request, extra_context=None, **kwargs):
+                       objects, extra_context = func(request=request, extra_context=extra_context, **kwargs)
        
-       @property
-       def page_number(self):
-               if not self.page:
-                       return None
-               
-               return self.page.number
+                       if 'HTTP_ACCEPT' in request.META and 'rss' in request.META['HTTP_ACCEPT'] and 'atom' not in request.META['HTTP_ACCEPT']:
+                               feed_type = 'rss'
+                       else:
+                               feed_type = 'atom'
+                       
+                       current_site = Site.objects.get_current()
+                       #Could this be done with request.path instead somehow?
+                       feed_kwargs = {
+                               'link': 'http://%s/%s/%s/' % (current_site.domain, request.node.get_absolute_url().strip('/'), reverse(reverse_name, urlconf=self, kwargs=kwargs).strip('/'))
+                       }
+                       feed = self.get_feed(feed_type, extra_context, feed_kwargs)
+                       
+                       for obj in objects:
+                               kwargs = {
+                                       'link': 'http://%s/%s/%s/' % (current_site.domain, request.node.get_absolute_url().strip('/'), self.get_subpath(obj).strip('/'))
+                               }
+                               self.add_item(feed, obj, kwargs=kwargs)
        
-       def __bool__(self):
-               return bool(self.paginator)
-
+                       response = HttpResponse(mimetype=feed.mime_type)
+                       feed.write(response, 'utf-8')
+                       return response
 
-def paginate(objects, per_page=None, page_number=1):
-       """
-       Given a list of objects, return a (page, obj_list) tuple.
-       """
-       try:
-               per_page = int(per_page)
-       except (TypeError, ValueError):
-               # Then either it wasn't set or it was set to an invalid value
-               return PaginationProxy(objects=objects)
+               return inner
        
-       # There also shouldn't be pagination if the list is too short. Try count()
-       # first - good chance it's a queryset, where count is more efficient.
-       try:
-               if objects.count() <= per_page:
-                       return PaginationProxy(objects=objects)
-       except AttributeError:
-               if len(objects) <= per_page:
-                       return PaginationProxy(objects=objects)
-       
-       paginator = Paginator(objects, per_page)
-       try:
-               page_number = int(page_number)
-       except:
-               page_number = 1
+       def get_feed(self, feed_type, extra_context, kwargs=None):
+               defaults = {
+                       'description': ''
+               }
+               defaults.update(kwargs or {})
+               
+               if feed_type == 'rss':
+                       return self.rss_feed(**defaults)
+               
+               if 'description' in defaults and defaults['description'] and 'subtitle' not in defaults:
+                       defaults['subtitle'] = defaults['description']
+               
+               return self.atom_feed(**defaults)
        
-       try:
-               page = paginator.page(page_number)
-       except EmptyPage:
-               page = None
+       def feed_patterns(self, object_fetcher, page, base_name):
+               urlpatterns = patterns('',
+                       url(r'^$', self.page_view(object_fetcher, page), name=base_name)
+               )
+               if self.feeds_enabled:
+                       feed_name = '%s_feed' % base_name
+                       urlpatterns = patterns('',
+                               url(r'^%s/$' % self.feed_suffix, self.feed_view(object_fetcher, feed_name), name=feed_name),
+                       ) + urlpatterns
+               return urlpatterns
        
-       return PaginationProxy(paginator, page, objects)
\ No newline at end of file
+       def add_item(self, feed, obj, kwargs=None):
+               defaults = kwargs or {}
+               feed.add_item(**defaults)
\ No newline at end of file