def test_calculate_period_end(self):
period = TimePeriod(1000)
start_time = self._get_time1()
period.start_period(start_time)
period_end = period.calculate_period_end()
expected_end_time = start_time + timedelta(seconds=1000)
assert period_end == expected_end_time
def test_calculate_period_end(self):
period = TimePeriod(1000)
start_time = self._get_time1()
period.start_period(start_time)
period_end = period.calculate_period_end()
expected_end_time = start_time + timedelta(seconds=1000)
assert period_end == expected_end_time
def test_reset(self):
period = TimePeriod(50, time_provider=self._get_time1)
period.start_period(self._get_time1())
period.reset()
assert period.period_start_time is None
assert period.period_started is False
def test_start_period(self):
start_time = self._get_time1()
period = TimePeriod(30, time_provider=TestTimePeriod._get_time1)
period.start_period()
assert period.period_start_time == start_time
assert period.period_started is True
assert period.period_length_in_seconds == 30
def test_start_period(self):
start_time = self._get_time1()
period = TimePeriod(30, time_provider=TestTimePeriod._get_time1)
period.start_period()
assert period.period_start_time == start_time
assert period.period_started is True
assert period.period_length_in_seconds == 30
def test_start_period_with_start_time(self):
start_time = self._get_time1()
period = TimePeriod(90)
period.start_period(start_time)
assert period.period_start_time == start_time
assert period.period_started is True
assert period.period_length_in_seconds == 90
def test_start_period_with_start_time(self):
start_time = self._get_time1()
period = TimePeriod(90)
period.start_period(start_time)
assert period.period_start_time == start_time
assert period.period_started is True
assert period.period_length_in_seconds == 90
def __init__(self, instance_uuid, policy):
self._logger = logging.getLogger(__name__)
self.state = ScalingStateUntriggered()
threshold_period_in_seconds = policy.get_threshold_period_in_seconds()
self._logger.debug("threshold period of policy %s is %d", policy,
threshold_period_in_seconds)
self.threshold_period = TimePeriod(threshold_period_in_seconds)
self._latest_metric_update = None
self.instance_uuid = instance_uuid
self.policy = policy
def test_init(self):
period_length = 464
period = TimePeriod(period_length)
assert period.period_started is False
assert period.period_length_in_seconds == period_length
assert period.period_start_time is None
def __init__(self, instance_uuid, policy):
self._logger = logging.getLogger(__name__)
self.state = ScalingStateUntriggered()
threshold_period_in_seconds = policy.get_threshold_period_in_seconds()
self._logger.debug("threshold period of policy %s is %d", policy, threshold_period_in_seconds)
self.threshold_period = TimePeriod(threshold_period_in_seconds)
self._latest_metric_update = None
self.instance_uuid = instance_uuid
self.policy = policy
def test_reset(self):
period = TimePeriod(50, time_provider=self._get_time1)
period.start_period(self._get_time1())
period.reset()
assert period.period_start_time is None
assert period.period_started is False
def __init__(self, scaling_policy_configuration, service,
scaling_policy_type):
self._logger = logging.getLogger(__name__)
self._policy_instances = {}
self.state = ScalingStateUntriggered()
self._policy_config = scaling_policy_configuration
self.service_type = self._policy_config.service_type
self.policy_name = scaling_policy_configuration.name
cooldown_period_in_seconds = self._calculate_period_in_seconds(
scaling_policy_configuration.cooldown_period,
scaling_policy_configuration.cooldown_period_unit)
self._logger.debug("cooldown period of policy %s is %d",
self.policy_name, cooldown_period_in_seconds)
self.cooldown_period = TimePeriod(cooldown_period_in_seconds)
self.service = service
self._last_in_period_uuid_of_service_type = {}
self._scaling_policy_type = scaling_policy_type
def test_is_in_period_with_specific_time(self):
start_time = self._get_time2()
period_length = timedelta(seconds=30)
period = TimePeriod(period_length.seconds,
time_provider=self._get_time2)
period.start_period()
in_period_time_1 = start_time + timedelta(seconds=30)
in_period_time_2 = start_time + timedelta(seconds=29)
in_period_time_3 = start_time + timedelta(seconds=1)
in_period_time_4 = start_time
out_period_time_1 = start_time + timedelta(seconds=31)
out_period_time_2 = start_time + timedelta(seconds=30, microseconds=1)
assert period.is_in_period(time=in_period_time_1) is True
assert period.is_in_period(time=in_period_time_2) is True
assert period.is_in_period(time=in_period_time_3) is True
assert period.is_in_period(time=in_period_time_4) is True
assert period.is_in_period(time=out_period_time_1) is False
assert period.is_in_period(time=out_period_time_2) is False
def test_is_in_period_with_specific_time(self):
start_time = self._get_time2()
period_length = timedelta(seconds=30)
period = TimePeriod(period_length.seconds, time_provider=self._get_time2)
period.start_period()
in_period_time_1 = start_time + timedelta(seconds=30)
in_period_time_2 = start_time + timedelta(seconds=29)
in_period_time_3 = start_time + timedelta(seconds=1)
in_period_time_4 = start_time
out_period_time_1 = start_time + timedelta(seconds=31)
out_period_time_2 = start_time + timedelta(seconds=30, microseconds=1)
assert period.is_in_period(time=in_period_time_1) is True
assert period.is_in_period(time=in_period_time_2) is True
assert period.is_in_period(time=in_period_time_3) is True
assert period.is_in_period(time=in_period_time_4) is True
assert period.is_in_period(time=out_period_time_1) is False
assert period.is_in_period(time=out_period_time_2) is False
def test_is_in_period_now(self):
start_time = self._get_time1()
period_length = timedelta(seconds=30)
in_period_time_1 = start_time + timedelta(seconds=30)
in_period_time_2 = start_time + timedelta(seconds=29)
in_period_time_3 = start_time + timedelta(seconds=1)
in_period_time_4 = start_time
out_period_time_1 = start_time + timedelta(seconds=31)
out_period_time_2 = start_time + timedelta(seconds=30, microseconds=1)
period = TimePeriod(period_length.seconds,
time_provider=lambda: in_period_time_1)
period.start_period(start_time)
assert period.is_in_period() is True
period = TimePeriod(period_length.seconds,
time_provider=lambda: in_period_time_2)
period.start_period(start_time)
assert period.is_in_period() is True
period = TimePeriod(period_length.seconds,
time_provider=lambda: in_period_time_3)
period.start_period(start_time)
assert period.is_in_period() is True
period = TimePeriod(period_length.seconds,
time_provider=lambda: in_period_time_4)
period.start_period(start_time)
assert period.is_in_period() is True
period = TimePeriod(period_length.seconds,
time_provider=lambda: out_period_time_1)
period.start_period(start_time)
assert period.is_in_period() is False
period = TimePeriod(period_length.seconds,
time_provider=lambda: out_period_time_2)
period.start_period(start_time)
assert period.is_in_period() is False
class ScalingPolicyInstance:
_latest_metric_update = None
state = None
policy = None
instance_uuid = None
threshold_period = None
def __init__(self, instance_uuid, policy):
self._logger = logging.getLogger(__name__)
self.state = ScalingStateUntriggered()
threshold_period_in_seconds = policy.get_threshold_period_in_seconds()
self._logger.debug("threshold period of policy %s is %d", policy, threshold_period_in_seconds)
self.threshold_period = TimePeriod(threshold_period_in_seconds)
self._latest_metric_update = None
self.instance_uuid = instance_uuid
self.policy = policy
def update_policy_state_and_get_scaling_actions(self, metrics_message):
scaling_actions = []
for metric_value in metrics_message.metric_values:
value = metric_value.value
timestamp = dateutil.parser.parse(metric_value.timestamp)
if not self._is_new_metric(timestamp):
self._logger.debug("metric value %s is outdated for instance %s", repr(metric_value), self.instance_uuid)
continue
if self.policy.cooldown_period.is_in_period(timestamp):
self._logger.debug("metric value %s ignored because of cooldown is active", repr(metric_value))
continue
predicate_satisfied = self.policy.value_exceeds_or_undercuts_threshold(float(value))
self._logger.debug("metric value %s is %s under/over threshold",
repr(metric_value),
"" if predicate_satisfied else "not"
)
cooldown_start_time = timestamp
if self.threshold_period.period_started:
cooldown_start_time = self.threshold_period.calculate_period_end()
action_required = self.state.update_and_report_if_action_required(
self,
predicate_satisfied,
timestamp,
metrics_message.uuid
)
if action_required:
scaling_action = self.policy.create_scaling_action(metrics_message.metric_name, self.instance_uuid)
self.policy.cooldown_period.start_period(cooldown_start_time)
scaling_actions.append(scaling_action)
self._logger.info("Triggered scaling action %s, beginning cooldown", repr(scaling_action))
return scaling_actions
def _is_new_metric(self, timestamp):
if self._latest_metric_update is None:
self._latest_metric_update = timestamp
return True
new_metric = timestamp > self._latest_metric_update
if new_metric:
self._latest_metric_update = timestamp
return new_metric
def __repr__(self):
return "ScalingPolicyInstance(instance_uuid={},state={},threshold_period={},policy={})".format(
self.instance_uuid,
repr(self.state),
repr(self.threshold_period),
self.policy.policy_name
)
def test_calculate_period_end_with_unstarted_period(self):
with pytest.raises(ValueError):
period = TimePeriod(1000)
period_end = period.calculate_period_end()
assert period_end is None
def test_calculate_period_end_with_unstarted_period(self):
with pytest.raises(ValueError):
period = TimePeriod(1000)
period_end = period.calculate_period_end()
assert period_end is None
class ScalingPolicyInstance:
_latest_metric_update = None
state = None
policy = None
instance_uuid = None
threshold_period = None
def __init__(self, instance_uuid, policy):
self._logger = logging.getLogger(__name__)
self.state = ScalingStateUntriggered()
threshold_period_in_seconds = policy.get_threshold_period_in_seconds()
self._logger.debug("threshold period of policy %s is %d", policy,
threshold_period_in_seconds)
self.threshold_period = TimePeriod(threshold_period_in_seconds)
self._latest_metric_update = None
self.instance_uuid = instance_uuid
self.policy = policy
def update_policy_state_and_get_scaling_actions(self, metrics_message):
scaling_actions = []
for metric_value in metrics_message.metric_values:
value = metric_value.value
timestamp = dateutil.parser.parse(metric_value.timestamp)
if not self._is_new_metric(timestamp):
self._logger.debug(
"metric value %s is outdated for instance %s",
repr(metric_value), self.instance_uuid)
continue
if self.policy.cooldown_period.is_in_period(timestamp):
self._logger.debug(
"metric value %s ignored because of cooldown is active",
repr(metric_value))
continue
predicate_satisfied = self.policy.value_exceeds_or_undercuts_threshold(
float(value))
self._logger.debug("metric value %s is %s under/over threshold",
repr(metric_value),
"" if predicate_satisfied else "not")
cooldown_start_time = timestamp
if self.threshold_period.period_started:
cooldown_start_time = self.threshold_period.calculate_period_end(
)
action_required = self.state.update_and_report_if_action_required(
self, predicate_satisfied, timestamp, metrics_message.uuid)
if action_required:
scaling_action = self.policy.create_scaling_action(
metrics_message.metric_name, self.instance_uuid)
self.policy.cooldown_period.start_period(cooldown_start_time)
scaling_actions.append(scaling_action)
self._logger.info(
"Triggered scaling action %s, beginning cooldown",
repr(scaling_action))
return scaling_actions
def _is_new_metric(self, timestamp):
if self._latest_metric_update is None:
self._latest_metric_update = timestamp
return True
new_metric = timestamp > self._latest_metric_update
if new_metric:
self._latest_metric_update = timestamp
return new_metric
def __repr__(self):
return "ScalingPolicyInstance(instance_uuid={},state={},threshold_period={},policy={})".format(
self.instance_uuid, repr(self.state), repr(self.threshold_period),
self.policy.policy_name)
def test_is_in_period_now(self):
start_time = self._get_time1()
period_length = timedelta(seconds=30)
in_period_time_1 = start_time + timedelta(seconds=30)
in_period_time_2 = start_time + timedelta(seconds=29)
in_period_time_3 = start_time + timedelta(seconds=1)
in_period_time_4 = start_time
out_period_time_1 = start_time + timedelta(seconds=31)
out_period_time_2 = start_time + timedelta(seconds=30, microseconds=1)
period = TimePeriod(period_length.seconds, time_provider=lambda: in_period_time_1)
period.start_period(start_time)
assert period.is_in_period() is True
period = TimePeriod(period_length.seconds, time_provider=lambda: in_period_time_2)
period.start_period(start_time)
assert period.is_in_period() is True
period = TimePeriod(period_length.seconds, time_provider=lambda: in_period_time_3)
period.start_period(start_time)
assert period.is_in_period() is True
period = TimePeriod(period_length.seconds, time_provider=lambda: in_period_time_4)
period.start_period(start_time)
assert period.is_in_period() is True
period = TimePeriod(period_length.seconds, time_provider=lambda: out_period_time_1)
period.start_period(start_time)
assert period.is_in_period() is False
period = TimePeriod(period_length.seconds, time_provider=lambda: out_period_time_2)
period.start_period(start_time)
assert period.is_in_period() is False
