Bandaid EventProgress logical error

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[linear]

ENG-404 Servox Measure runs indefinitely when duration is set to 0

Initially reported by @eric

This appears to be caused by the implementation of EventProgress used by the measure connector. See trace of aberrant logic below:

• Prometheus measure creates an EventProgress with the control duration of 0: 

  servox/servo/connectors/prometheus.py

  Lines 868 to 883 in 506d1c4

  	measurement_duration = servo.Duration(control.warmup + control.duration)
  	self.logger.info(
  	f"Measuring {len(metrics__)} metrics for {measurement_duration}: {servo.utilities.join_to_series(measuring_names)}"
  	)
  	# Handle eager metrics
  	eager_metrics = list(filter(lambda m: m.eager, metrics__))
  	eager_settlement = max(eager_metrics, key=operator.attrgetter("eager")).eager if eager_metrics else None
  	eager_observer = EagerMetricObserver(base_url=self.config.base_url, metrics=eager_metrics, start=start, end=end)
  	if eager_metrics:
  	servo.logger.info(f"Observing values of {len(eager_metrics)} eager metrics: measurement will return after {eager_settlement} of stability")
  	else:
  	servo.logger.debug(f"No eager metrics found: measurement will proceed for full duration of {measurement_duration}")
  	# Allow the maximum settlement time of eager metrics to elapse before eager return (None runs full duration)
  	progress = servo.EventProgress(timeout=measurement_duration, settlement=eager_settlement)

• EventProgress.watch loops infinitely until the finished property returns true: https://github.com/opsani/servox/blob/main/servo/types.py#L309-L314
• EventProgress.finished returns true when timed_out is true progress >= 100: 

  servox/servo/types.py

  Line 465 in 506d1c4

  return self.timed_out or super().finished

• EventProgress.timed_out always returns false if timeout is falsey: 

  servox/servo/types.py

  Line 460 in 506d1c4

  if not self.timeout or not self.started: return False

• EventProgress.progress always returns 0 if timeout is falsey which is the case with a duration of 0: 

  servox/servo/types.py

  Line 551 in 506d1c4

  return 0.0