U n^=@sddlZddlZGdddeZGdddeZGdddeZGdd d eZGd d d eZGd d d eZ GdddeZ GdddeZ dS)NcseZdZfddZZS)RequestExceededExceptioncs,||_||_d||f}tt||dS)aError when requested amount exceeds what is allowed The request that raised this error should be retried after waiting the time specified by ``retry_time``. :type requested_amt: int :param requested_amt: The originally requested byte amount :type retry_time: float :param retry_time: The length in time to wait to retry for the requested amount zeZdZdddZddZddZdd Zd d Zd d ZdS) LeakyBucketNcCsZt||_||_|dkr t|_t|_||_|dkr@t|_||_ |dkrVt |_ dS)a9A leaky bucket abstraction to limit bandwidth consumption :type rate: int :type rate: The maximum rate to allow. This rate is in terms of bytes per second. :type time_utils: TimeUtils :param time_utils: The time utility to use for interacting with time :type rate_tracker: BandwidthRateTracker :param rate_tracker: Tracks bandwidth consumption :type consumption_scheduler: ConsumptionScheduler :param consumption_scheduler: Schedules consumption retries when necessary N) float _max_raterr threadingLock_lock _rate_trackerBandwidthRateTracker_consumption_schedulerConsumptionScheduler)rZmax_raterZ rate_trackerZconsumption_schedulerr r r rs  zLeakyBucket.__init__c Csz|jj|j}|j|r8||||W5QRS|||rT||||n|||W5QRSW5QRXdS)acConsume an a requested amount :type amt: int :param amt: The amount of bytes to request to consume :type request_token: RequestToken :param request_token: The token associated to the consumption request that is used to identify the request. 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Specifically it is used in the following calculation: current_rate = alpha * new_rate + (1 - alpha) * current_rate This value of this constant should be between 0 and 1. N)_alpha _last_time _current_rate)ralphar r r rVs zBandwidthRateTracker.__init__cCs|jdkrdS|jS)zmThe current transfer rate :rtype: float :returns: The current tracked transfer rate N)r\r]rr r r current_ratefs z!BandwidthRateTracker.current_ratecCs|jdkrdS|||S)aZGet the projected rate using a provided amount and time :type amt: int :param amt: The proposed amount to consume :type time_at_consumption: float :param time_at_consumption: The proposed time to consume at :rtype: float :returns: The consumption rate if that amt and time were consumed Nr_)r\*_calculate_exponential_moving_average_raterrMtime_at_consumptionr r r rPqs z'BandwidthRateTracker.get_projected_ratecCs2|jdkr||_d|_dS||||_||_dS)aRecord the consumption rate based off amount and time point :type amt: int :param amt: The amount that got consumed :type time_at_consumption: float :param time_at_consumption: The time at which the amount was consumed Nr_)r\r]rarbr r r rSs z,BandwidthRateTracker.record_consumption_ratecCs"||j}|dkrtdS||S)Nrinf)r\r>)rrMrcZ time_deltar r r _calculate_rates z$BandwidthRateTracker._calculate_ratecCs&|||}|j|d|j|jS)N)rer[r])rrMrcZnew_rater r r ras z?BandwidthRateTracker._calculate_exponential_moving_average_rateN)rZ) r rrrpropertyr`rPrSrerar r r r rDUs   rD) rr@ Exceptionrobjectrrrrr=rFrDr r r r  s%jR5