Digging your sharp hooks in

# begin
class HookEventHandler(metaclass=abc.ABCMeta):
    def __init__(self, hook_event):
        self.hook_event = hook_event
    @abc.abstractmethod
    def process(self):
        pass
    def response(self, response_data):
        return HttpResponse(json.dumps(response_data), content_type='application/json')
    @classmethod
    def choose(cls, funnel_path):
        if funnel_path == '':
            return cls._HANDLER_CLASSES['test']
        for prefix, klass in cls._HANDLER_CLASSES.items():
            if funnel_path.startswith(prefix):
                return klass
        return None

class TestFunnelHookEventHandler(HookEventHandler):
    def process(self):
        return self.response({'hook_event_id': self.hook_event.id})

class TddPythonFunnelHookEventHandler(HookEventHandler):
    def process(self):
        response_data = {'hook_event_id': self.hook_event.id}
        try:
            body_data = self.hook_event.json()
        except json.JSONDecodeError:
            raise CFException(self.hook_event.id)
        if 'purchase' in body_data:
            if 'event' not in body_data:
                raise CFException(self.hook_event.id)
            if body_data['event'] == 'created':
                hp = HookPurchase.from_event(self.hook_event, body_data)
                response_data['hook_purchase_id'] = hp.id
                if hp.is_primary():
                    send_register_email(hp.email, mk_register_url(hp.purchase.retrieval_key), 'Test-Driven Python + Bonuses')
        return self.response(response_data)

HookEventHandler._HANDLER_CLASSES = {
    'tdd-python': TddPythonFunnelHookEventHandler,
    'test': TestFunnelHookEventHandler,
}
# end