Load JSON from the request body and store them in
        self.request.arguments, like Tornado does by default for POSTed form
        parameters.

        If JSON cannot be decoded

        :raises ValueError: JSON Could not be decoded

def load_json(self):
        """Load JSON from the request body and store them in
        self.request.arguments, like Tornado does by default for POSTed form
        parameters.

        If JSON cannot be decoded

        :raises ValueError: JSON Could not be decoded
        """
        try:
            self.request.arguments = json.loads(self.request.body)
        except ValueError:
            msg = "Could not decode JSON: %s" % self.request.body
            self.logger.debug(msg)
            self.raise_error(400, msg)