post.rb

@@ -0,0 +1,26 @@
+class Post
+  include MongoMapper::Document
+
+  key :title,       String
+  key :url,         String
+  key :author,      String
+  key :summary,     String
+  key :content,     String
+  key :published,   Time
+  key :loc,         Hash # { lng, lat }
+  timestamps!
+
+  ensure_index [[:loc, '2d']]
+
+  belongs_to :feed
+  
+  EARTH_RADIUS_M = 6378000
+  
+  def self.near(lat, lng, radius_m)
+    all(
+      :loc => {
+        '$nearSphere' => [ lng, lat ],
+        '$maxDistance' => radius_m / EARTH_RADIUS_M
+    })
+  end
+end