Twelfth Week NewsFeed Update

As the GSOC program wraps up, I'm finishing with refactoring and testing, and have added a couple new important features in the last week:

* Subscribe-By-Star. The subscribe-by-star pattern allows for an e-mail subscription for a particular entity to be added or removed by toggling a star on the news feed box on or off. Aside from the popup help message explaining how the feature work, the subscribe-by-star is working on http://jamstage.appspot.com.

The ajax itself is simple. After using jQuery.ajax() to make the call, I first process the POST data so that it is suitable for logic (converting byte strings to native types, mostly):


def edit_subscription(request, *args, **kwargs):
if request.GET.get('entity_key'):
entity_key = request.GET.get('entity_key')
else:
return http.HttpResponseServerError()
if request.GET.get('subscribe') == 'true':
subscribe = True
elif request.GET.get('subscribe') == 'false':
subscribe = False
else:
return http.HttpResponseServerError()
subscription_logic.editEntitySubscription(entity_key, subscribe)
return http.HttpResponse('OK')


I then call the editEntitySubscription subscription logic method:


entity_key = db.Key(entity_key)
user = user_logic.getForCurrentAccount()
subscriber = self.getSubscriberForUser(user)
if subscribe and entity_key not in subscriber.subscriptions:
subscriber.subscriptions.append(entity_key)
logging.info('added subscription for entity_key %s for user %s'
% (entity_key, user.key().name()))
elif not subscribe and entity_key in subscriber.subscriptions:
subscriber.subscriptions.remove(entity_key)
logging.info('removed subscription for entity_key %s for user %s'
% (entity_key, user.key().name()))
else: return
db.put(subscriber)


I've also added a model-based class method for determining auto-subscriptions, which will help for what I've found to be the hardest part of this project. While the goal is simply to get all users with at least read-access to an arbitrary Linkable entity, it is actually very difficult, and when possible it's only from manually creating logic. Essentially, this list of users should be sharded into its own relational entity (just a reference to the Linkable and a ListProperty of users). And I've also made various other rafactorings of the subscription code.


I look forward to committing code this week! At almost 2,000 lines, this will be a big commit, but worth the effort.