Budget planning
Converts an explicit window and availability target into a simple time-based downtime allowance.
Day 048 / DevOps / Availability
Uptime SLA Calculator
/ Overview
A dependency-free Python CLI that turns a time-based availability target into a downtime budget and compares supplied downtime using decimal arithmetic.
An availability percentage is easier to interpret when it is expressed as minutes in a defined measurement window. Rounding the displayed percentage can also hide a small overrun, so the budget comparison needs to remain separate from display formatting.
/ Provided servicesClear thinking.
Clear thinking.
Practical delivery.
Boundary clarity
Uses the unrounded budget for status while formatting observed availability separately.
Documented scope
Explains that calendar assumptions, exclusions, partial failures and contract rules need separate treatment.
/ Solution
Uptime SLA Calculator uses decimal arithmetic to calculate window minutes, allowed downtime, remaining budget and observed availability. It accepts fractional day windows, compares downtime against the unrounded budget, and reports text or JSON with clear exit codes. It does not monitor services, merge incident intervals, evaluate contractual exclusions or calculate service credits.
/ Impact
Explicit measurement windows
Decimal downtime budgets
Observed availability
Remaining or exceeded minutes
Exact boundary classification
Bounded numeric validation
Text and JSON reports
Ten standard-library tests
Python standard library
Decimal, argparse and JSON provide the dependency-free CLI.
Defensive inputs
Rejects non-finite values, invalid windows, targets and downtime outside the measurement period.
Unittest
Ten tests cover exact boundaries, tiny overruns, full outages, fractional windows, input validation and CLI JSON exit behavior.