Looks like maybe most of your handlers here are returning json. Might make sense to build a base handler that does this for you.

``` py
class JsonHandler(webapp2.RequestHandler):

    def write_json_result(self, payload, **kwargs):
        self.response.out.write(json.dumps(payload, **kwargs))


class DisplayLogs(JsonHandler):

    def post(self):
         from_date = json.loads(self.request.get('from_date'))
         .....
         self.write_json_result(show_filtered_logs(from_date, to_date))
```