def notify_subscribers(resource)
      resource.subscriptions.each do |subscription|
        http = EM::HttpRequest.new(subscription.url).post(:body => {:data => resource.body})
        http.callback{ |response|
          puts "POSTed updated data for #{resource.url}, #{resource.body.length} characters"
        }
        http.errback {|response|
          # Do something here, maybe setting the resource
          # to be not checked anymore.
        }
      end
    end
def notify_subscribers(resource)
      resource.subscriptions.each do |subscription|
        http = EM::HttpRequest.new(subscription.url).post(:body => {:data => resource.body})
        http.callback{ |response|
          puts "POSTed updated data for #{resource.url}, #{resource.body.length} characters"
        }
        http.errback {|response|
          # Do something here, maybe setting the resource
          # to be not checked anymore.
        }
      end
    end
Notifies each of a NetResource's subscribers that the resource has changed
 by doing an HTTP POST request to the subscriber's callback url.

 The POST body contains a key called "data" which contains the feed value.