Ticket #6547: georss_syndication_patch_v4.diff

django/contrib/gis/feeds.py

@@ +1 @@
+from django.contrib.syndication.feeds import Feed as BaseFeed, FeedDoesNotExist
+from django.utils.feedgenerator import Atom1Feed, Rss201rev2Feed
+
+class GeoFeedMixin(object):
+    w3c_geo = False
+
+    def georss_coords(self, coords):
+        """
+        In GeoRSS coordinate pairs are ordered by lat/lon and separated by
+        a single white space.  Given a tuple of coordinates, this will return
+        a unicode GeoRSS representation.
+        """
+        return u' '.join([u'%f %f' % (coord[1], coord[0]) for coord in coords])
+
+    def add_georss_point(self, handler, coords):
+        """
+        Adds a GeoRSS point with the given coords using the given handler.
+        Handles the differences between simple GeoRSS and the more pouplar
+        W3C Geo specification.
+        """
+        if self.w3c_geo:
+            lon, lat = coords[:2]
+            handler.addQuickElement(u'geo:lat', u'%f' % lat)
+            handler.addQuickElement(u'geo:lon', u'%f' % lon)
+        else:
+            handler.addQuickElement(u'georss:point', self.georss_coords((coords,)))
+
+    def add_georss_element(self, handler, item):
+        """
+        This routine adds a GeoRSS XML element using the given item and handler.
+        """
+        # Getting the Geometry object.
+        geom = item.get('geometry', None)
+        if not geom is None:
+            if isinstance(geom, (list, tuple)):
+                # Special case if a tuple/list was passed in.  The tuple may be
+                # a point or a box
+                box_coords = None
+                if isinstance(geom[0], (list, tuple)):
+                    # Box: ( (X0, Y0), (X1, Y1) )
+                    if len(geom) == 2:
+                        box_coords = geom
+                    else:
+                        raise ValueError('Only should be two sets of coordinates.')
+                else:
+                    if len(geom) == 2:
+                        # Point: (X, Y)
+                        self.add_georss_point(handler, geom)
+                    elif len(geom) == 4:
+                        # Box: (X0, Y0, X1, Y1)
+                        box_coords = (geom[:2], geom[2:])
+                    else:
+                        raise ValueError('Only should be 2 or 4 numeric elements.')
+                # If a GeoRSS box was given via tuple.
+                if not box_coords is None:
+                    if self.w3c_geo: raise ValueError('Cannot use simple GeoRSS box in W3C Geo feeds.')
+                    handler.addQuickElement(u'georss:box', self.georss_coords(box_coords))
+            else:
+                # Getting the lower-case geometry type.
+                gtype = str(geom.geom_type).lower()
+             
+                if gtype == 'point':
+                    self.add_georss_point(handler, geom.coords) 
+                else:
+                    if self.w3c_geo: raise TypeError('W3C Geo only supports Point geometries.')
+                    # For formatting consistent w/the GeoRSS simple standard:
+                    # http://georss.org/1.0#simple
+                    if gtype in ('linestring', 'linearring'):
+                        handler.addQuickElement(u'georss:line', self.georss_coords(geom.coords))
+                    elif gtype in ('polygon',):
+                        # Only support the exterior ring.
+                        handler.addQuickElement(u'georss:polygon', self.georss_coords(geom[0].coords))
+                    else:
+                        raise TypeError('Geometry type "%s" not supported.' % geom.geom_type)
+
+### SyndicationFeed subclasses ###
+class W3CGeoFeed(Rss201rev2Feed, GeoFeedMixin):
+    w3c_geo = True
+
+    def rss_attributes(self):
+        attrs = super(W3CGeoFeed, self).rss_attributes()
+        attrs[u'xmlns:geo'] = u'http://www.w3.org/2003/01/geo/wgs84_pos#'
+        return attrs
+
+    def add_item_elements(self, handler, item):
+        super(W3CGeoFeed, self).add_item_elements(handler, item)
+        self.add_georss_element(handler, item)
+
+    def add_root_elements(self, handler):
+        super(W3CGeoFeed, self).add_root_elements(handler)
+        self.add_georss_element(handler, self.feed)
+
+class GeoRSSFeed(Rss201rev2Feed, GeoFeedMixin):
+    def rss_attributes(self):
+        attrs = super(GeoRSSFeed, self).rss_attributes()
+        attrs[u'xmlns:georss'] = u'http://www.georss.org/georss'
+        return attrs
+
+    def add_item_elements(self, handler, item):
+        super(GeoRSSFeed, self).add_item_elements(handler, item)
+        self.add_georss_element(handler, item)
+
+    def add_root_elements(self, handler):
+        super(GeoRSSFeed, self).add_root_elements(handler)
+        self.add_georss_element(handler, self.feed)
+
+class GeoAtom1Feed(Atom1Feed, GeoFeedMixin):
+    def root_attributes(self):
+        attrs = super(GeoAtom1Feed, self).root_attributes()
+        attrs[u'xmlns:georss'] = u'http://www.georss.org/georss'
+        return attrs
+
+    def add_item_elements(self, handler, item):
+        super(GeoAtom1Feed, self).add_item_elements(handler, item)
+        self.add_georss_element(handler, item)
+
+    def add_root_elements(self, handler):
+        super(GeoAtom1Feed, self).add_root_elements(handler)
+        self.add_georss_element(handler, self.feed)
+        
+class Feed(BaseFeed):
+    """
+    This is a subclass of the `Feed` from `django.contrib.syndication`.
+    This allows users to define a `geometry(obj)` and/or `item_geometry(item)`
+    methods on their own subclasses so that geo-referenced information may
+    placed in the feed.
+    """
+    feed_type = GeoRSSFeed
+
+    def feed_extra_kwargs(self, obj):
+        return {'geometry' : self.__get_dynamic_attr('geometry', obj)}
+
+    def item_extra_kwargs(self, item):
+        return {'geometry' : self.__get_dynamic_attr('item_geometry', item)}

django/contrib/syndication/feeds.py

@@ -59 +59 @@
                 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
 
@@ -100 +114 @@
             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:
@@ -158 +173 @@
                 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