'''Generate statistics about the percentage of time spent in different

def __init__(self, summation_period=10):

'''Reports will always cover the most recent period of summation_period

self.period = summation_period

self.status_history = [ {'start': 0, 'end': None, 'status': CommonService.SERVICE_STATUS_NEW} ]

def update_status(self, new_status):

'''Record a status change with a current timestamp.'''

timestamp = time.time()

self.status_history[-1]['end'] = timestamp

self.status_history.append({'start': timestamp, 'end': None, 'status': new_status})

def report(self):

'''Return a dictionary of different status codes and the percentage of time

timestamp = time.time()

cutoff = timestamp - self.period

truncate = 0

summary = {}

for event in self.status_history[:-1]:

if event['end'] < cutoff:

truncate = truncate + 1

continue

summary[event['status']] = summary.get(event['status'], 0) + \

event['end'] - max(cutoff, event['start'])

summary[self.status_history[-1]['status']] = \

summary.get(self.status_history[-1]['status'], 0) + \

timestamp - max(cutoff, self.status_history[-1]['start'])

if truncate:

self.status_history = self.status_history[truncate:]

total_duration = sum(summary.values())

summary = { s: round(d / total_duration, 4) for s, d in summary.items() }