def shed()

in source/lambda/shared/elb_load_monitor/elb_listener_rule.py [0:0]

• 39 lines of code
• 10 McCabe index (conditional complexity)

    def shed(self, source_group_arn: str, weight_to_shed: int, max_shed_weight: int) -> None:
        if source_group_arn not in self.forward_configs:
            logger.debug('No target group ' + source_group_arn + ' found for rule ' + self.elb_rule_arn +
                         ' nothing to shed')

            return

        current_source_weight = self.forward_configs.get(source_group_arn)

        if max_shed_weight == (100 - current_source_weight):
            logger.debug(
                'No more load permitted to be shed for ' + source_group_arn)

            return

        new_source_weight = current_source_weight - weight_to_shed

        if max_shed_weight < (100 - new_source_weight):
            new_source_weight = 100 - max_shed_weight
            weight_to_shed = current_source_weight - new_source_weight

            logger.debug(
                'Desired shed amount exceeds total maximum shed amount, shedding by new amount:' + str(weight_to_shed))

        # if new_source_weight < 0:
        #    # source weight cannot be < 0
        #    new_source_weight = 0

        self.forward_configs[source_group_arn] = new_source_weight

        logger.debug('Shedding ' + str(weight_to_shed) +
                     ' percent from ' + source_group_arn + '. new weight: ' + str(self.forward_configs[source_group_arn]))

        per_target_weight_to_shed = weight_to_shed

        num_forwards = len(self.forward_configs)
        remainder_weight = 0

        if num_forwards > 2:
            # if more than 2 forward configs, then split the weight evenly among the remaining 2 targets
            div_mod = divmod(weight_to_shed, (len(self.forward_configs) - 1))
            per_target_weight_to_shed = div_mod[0]
            remainder_weight = div_mod[1]

        for key in self.forward_configs.keys():
            num_forwards -= 1
            if key == source_group_arn:
                continue

            new_weight = self.forward_configs.get(
                key) + per_target_weight_to_shed

            if (num_forwards == 0):
                new_weight += remainder_weight

            logger.debug('Receiving ' + str(per_target_weight_to_shed) +
                         ' percent from ' + source_group_arn + ' on ' +
                         key + '. New load in : ' + key + ' ' + str(new_weight))

            self.forward_configs[key] = new_weight

        return