scripts/slo_math.py

"""Basic math for event-based SLOs; never infer missing traffic counts."""

def calculate_slo(total: int, bad: int, objective: float) -> dict:
    if isinstance(total,bool) or isinstance(bad,bool) or not isinstance(total,int) or not isinstance(bad,int):raise ValueError('counts must be integers')
    if total<=0 or bad<0 or bad>total: raise ValueError('counts out of range')
    if not isinstance(objective,(float,int)) or isinstance(objective,bool) or not 0<objective<1: raise ValueError('objective must be fraction between 0 and 1')
    allowed=total*(1-objective)
    good=total-bad
    return {'total':total,'bad':bad,'good':good,'success_fraction':good/total,'target_fraction':float(objective),'allowed_bad_events':allowed,'remaining_bad_events':allowed-bad,'met':good/total>=objective}