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FA-10146 / Deployment models / Open access

Replica rollout status: Old-revision replicas count as updated · case 01

Old-revision replicas count as updated.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The implementation substitutes if False: for if updated < desired:, so old-revision replicas count as updated.

VERIFIED REPAIR

Require at least the desired updated replica count.

Unsuccessful approach: The attempted repair substitutes if updated <= desired:. Fixture 6 still yields 'progressing' instead of 'ready'.

Case contract

Report blocked on invalid specification, degraded on failed required replicas, progressing when observed generation lags, progressing when updated or available counts are below desired, otherwise ready. Zero desired is ready when observed.

Why this case matters

An offline model of replica rollout status, suitable for testing build and release tooling without external services.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(valid, failed, observed, generation, updated, available, desired):
    if not valid: return 'blocked'
    if failed: return 'degraded'
    if observed < generation: return 'progressing'
    if False: return 'progressing'
    if available < desired: return 'progressing'
    return 'ready'
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve(False, False, 1, 1, 1, 1, 1), 'blocked')
check('fixture 2', solve(True, True, 1, 1, 1, 1, 1), 'degraded')
check('fixture 3', solve(True, False, 0, 1, 1, 1, 1), 'progressing')
check('fixture 4', solve(True, False, 1, 1, 0, 1, 1), 'progressing')
check('fixture 5', solve(True, False, 1, 1, 1, 0, 1), 'progressing')
check('fixture 6', solve(True, False, 1, 1, 1, 1, 1), 'ready')
check('fixture 7', solve(True, False, 1, 1, 0, 0, 0), 'ready')
check('fixture 8', solve(True, False, 2, 1, 2, 2, 1), 'ready')
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 1blockedblockedPassed
fixture 2degradeddegradedPassed
fixture 3progressingprogressingPassed
fixture 4readyprogressingFailed
fixture 5progressingprogressingPassed
fixture 6readyreadyPassed
fixture 7readyreadyPassed
fixture 8readyreadyPassed

SHA-256 / ee69c847642b1247e26a996f3bf4f75292fa965ef609aae30e5120b3e6ef8872

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(valid, failed, observed, generation, updated, available, desired):
    if not valid: return 'blocked'
    if failed: return 'degraded'
    if observed < generation: return 'progressing'
    if updated <= desired: return 'progressing'
    if available < desired: return 'progressing'
    return 'ready'
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve(False, False, 1, 1, 1, 1, 1), 'blocked')
check('fixture 2', solve(True, True, 1, 1, 1, 1, 1), 'degraded')
check('fixture 3', solve(True, False, 0, 1, 1, 1, 1), 'progressing')
check('fixture 4', solve(True, False, 1, 1, 0, 1, 1), 'progressing')
check('fixture 5', solve(True, False, 1, 1, 1, 0, 1), 'progressing')
check('fixture 6', solve(True, False, 1, 1, 1, 1, 1), 'ready')
check('fixture 7', solve(True, False, 1, 1, 0, 0, 0), 'ready')
check('fixture 8', solve(True, False, 2, 1, 2, 2, 1), 'ready')
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 1blockedblockedPassed
fixture 2degradeddegradedPassed
fixture 3progressingprogressingPassed
fixture 4progressingprogressingPassed
fixture 5progressingprogressingPassed
fixture 6progressingreadyFailed
fixture 7progressingreadyFailed
fixture 8readyreadyPassed

SHA-256 / e752c0501a8c21463180e5d51ecdceec8795afb288b6149f173a6d9fb0179e08

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(valid, failed, observed, generation, updated, available, desired):
    if not valid: return 'blocked'
    if failed: return 'degraded'
    if observed < generation: return 'progressing'
    if updated < desired: return 'progressing'
    if available < desired: return 'progressing'
    return 'ready'
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve(False, False, 1, 1, 1, 1, 1), 'blocked')
check('fixture 2', solve(True, True, 1, 1, 1, 1, 1), 'degraded')
check('fixture 3', solve(True, False, 0, 1, 1, 1, 1), 'progressing')
check('fixture 4', solve(True, False, 1, 1, 0, 1, 1), 'progressing')
check('fixture 5', solve(True, False, 1, 1, 1, 0, 1), 'progressing')
check('fixture 6', solve(True, False, 1, 1, 1, 1, 1), 'ready')
check('fixture 7', solve(True, False, 1, 1, 0, 0, 0), 'ready')
check('fixture 8', solve(True, False, 2, 1, 2, 2, 1), 'ready')
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
fixture 1blockedblockedPassed
fixture 2degradeddegradedPassed
fixture 3progressingprogressingPassed
fixture 4progressingprogressingPassed
fixture 5progressingprogressingPassed
fixture 6readyreadyPassed
fixture 7readyreadyPassed
fixture 8readyreadyPassed

SHA-256 / ec4f78ec9cf74394799a50ebfe7fd63525c297579689fdb23b5cdc789a04ad0a

Verification & scope

This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:38:36.234501+00:00.

Case digest / d475221eeede8b09ade1dbdb662bb47ed399b01573d2f00fc043c1aef0aa5fdc