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FA-29221 / HTTP redirects / Open access

Compose explicit redirect policy decisions with veto precedence and reason retention: decision reasons ordered · case 01

Compose explicit redirect policy decisions with veto precedence and reason retention: the decision reasons ordered branch emits an incorrect decision.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The decision-reasons-ordered decision uses 'sorted(k for k,v in decisions)'; this violates the stipulated controller policy.

VERIFIED REPAIR

At this decision use '[k for k,v in decisions]', preserving the other controller outputs.

Unsuccessful approach: The partial repair uses '[k for k,v in reversed(decisions)]' and still fails an explicit boundary or control.

Case contract

Compose explicit redirect policy decisions with veto precedence and reason retention. The explicit fixture inputs and outputs define a bounded offline policy; request identity must accompany the decision.

Why this case matters

Models a redirect controller decision before following a target or exposing a redirect result.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
from urllib.parse import urlsplit, unquote, quote
import posixpath
import re
N = 1
observations = []
def solve(request, decisions, mode, inspected, override, target):
    return {'request': request, 'decision': [all(v for k,v in decisions), next((k for k,v in decisions if not v),None), [k for k,v in decisions if not v], mode == 'follow' and inspected, override and mode != 'error', mode == 'manual', sorted(k for k,v in decisions), target is not None and override, sum(not v for k,v in decisions), inspected and all(v for k,v in decisions)]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', [['scheme', True], ['host', False], ['port', True]], 'follow', True, False, '/b'), {'request': '/requests/' + str(N) + '/0', 'decision': [False, 'host', ['host'], True, False, False, ['scheme', 'host', 'port'], False, 1, False]})
check('fixture 2', solve('/requests/' + str(N) + '/1', [['scheme', True], ['host', True]], 'manual', False, False, '/c'), {'request': '/requests/' + str(N) + '/1', 'decision': [True, None, [], False, False, True, ['scheme', 'host'], False, 0, False]})
check('fixture 3', solve('/requests/' + str(N) + '/2', [], 'error', True, True, '/d'), {'request': '/requests/' + str(N) + '/2', 'decision': [True, None, [], False, False, False, [], True, 0, True]})
check('fixture 4', solve('/requests/' + str(N) + '/3', [['host', False], ['port', False]], 'follow', True, True, '/e'), {'request': '/requests/' + str(N) + '/3', 'decision': [False, 'host', ['host', 'port'], True, True, False, ['host', 'port'], True, 2, False]})
check('fixture 5', solve('/requests/' + str(N) + '/4', [['scheme', True]], 'follow', False, False, None), {'request': '/requests/' + str(N) + '/4', 'decision': [True, None, [], False, False, False, ['scheme'], False, 0, False]})
check('fixture 6', solve('/requests/' + str(N) + '/5', [['scheme', False], ['host', True]], 'manual', True, True, '/f'), {'request': '/requests/' + str(N) + '/5', 'decision': [False, 'scheme', ['scheme'], False, True, True, ['scheme', 'host'], True, 1, False]})
check('fixture 7', solve('/requests/' + str(N) + '/6', [['x', True]], 'follow', True, True, None), {'request': '/requests/' + str(N) + '/6', 'decision': [True, None, [], True, True, False, ['x'], False, 0, True]})
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 1{'decision': [False, 'host', ['host'], True, False, False, ['host', 'port', 'scheme'], False, 1, False], 'request': '/requests/1/0'}{'decision': [False, 'host', ['host'], True, False, False, ['scheme', 'host', 'port'], False, 1, False], 'request': '/requests/1/0'}Failed
fixture 2{'decision': [True, None, [], False, False, True, ['host', 'scheme'], False, 0, False], 'request': '/requests/1/1'}{'decision': [True, None, [], False, False, True, ['scheme', 'host'], False, 0, False], 'request': '/requests/1/1'}Failed
fixture 3{'decision': [True, None, [], False, False, False, [], True, 0, True], 'request': '/requests/1/2'}{'decision': [True, None, [], False, False, False, [], True, 0, True], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [False, 'host', ['host', 'port'], True, True, False, ['host', 'port'], True, 2, False], 'request': '/requests/1/3'}{'decision': [False, 'host', ['host', 'port'], True, True, False, ['host', 'port'], True, 2, False], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [True, None, [], False, False, False, ['scheme'], False, 0, False], 'request': '/requests/1/4'}{'decision': [True, None, [], False, False, False, ['scheme'], False, 0, False], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [False, 'scheme', ['scheme'], False, True, True, ['host', 'scheme'], True, 1, False], 'request': '/requests/1/5'}{'decision': [False, 'scheme', ['scheme'], False, True, True, ['scheme', 'host'], True, 1, False], 'request': '/requests/1/5'}Failed
fixture 7{'decision': [True, None, [], True, True, False, ['x'], False, 0, True], 'request': '/requests/1/6'}{'decision': [True, None, [], True, True, False, ['x'], False, 0, True], 'request': '/requests/1/6'}Passed

SHA-256 / ca73c417e14a25a1966c51394c223c214052f24092e924ac65110cc63f8a84f8

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
from urllib.parse import urlsplit, unquote, quote
import posixpath
import re
N = 1
observations = []
def solve(request, decisions, mode, inspected, override, target):
    return {'request': request, 'decision': [all(v for k,v in decisions), next((k for k,v in decisions if not v),None), [k for k,v in decisions if not v], mode == 'follow' and inspected, override and mode != 'error', mode == 'manual', [k for k,v in reversed(decisions)], target is not None and override, sum(not v for k,v in decisions), inspected and all(v for k,v in decisions)]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', [['scheme', True], ['host', False], ['port', True]], 'follow', True, False, '/b'), {'request': '/requests/' + str(N) + '/0', 'decision': [False, 'host', ['host'], True, False, False, ['scheme', 'host', 'port'], False, 1, False]})
check('fixture 2', solve('/requests/' + str(N) + '/1', [['scheme', True], ['host', True]], 'manual', False, False, '/c'), {'request': '/requests/' + str(N) + '/1', 'decision': [True, None, [], False, False, True, ['scheme', 'host'], False, 0, False]})
check('fixture 3', solve('/requests/' + str(N) + '/2', [], 'error', True, True, '/d'), {'request': '/requests/' + str(N) + '/2', 'decision': [True, None, [], False, False, False, [], True, 0, True]})
check('fixture 4', solve('/requests/' + str(N) + '/3', [['host', False], ['port', False]], 'follow', True, True, '/e'), {'request': '/requests/' + str(N) + '/3', 'decision': [False, 'host', ['host', 'port'], True, True, False, ['host', 'port'], True, 2, False]})
check('fixture 5', solve('/requests/' + str(N) + '/4', [['scheme', True]], 'follow', False, False, None), {'request': '/requests/' + str(N) + '/4', 'decision': [True, None, [], False, False, False, ['scheme'], False, 0, False]})
check('fixture 6', solve('/requests/' + str(N) + '/5', [['scheme', False], ['host', True]], 'manual', True, True, '/f'), {'request': '/requests/' + str(N) + '/5', 'decision': [False, 'scheme', ['scheme'], False, True, True, ['scheme', 'host'], True, 1, False]})
check('fixture 7', solve('/requests/' + str(N) + '/6', [['x', True]], 'follow', True, True, None), {'request': '/requests/' + str(N) + '/6', 'decision': [True, None, [], True, True, False, ['x'], False, 0, True]})
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 1{'decision': [False, 'host', ['host'], True, False, False, ['port', 'host', 'scheme'], False, 1, False], 'request': '/requests/1/0'}{'decision': [False, 'host', ['host'], True, False, False, ['scheme', 'host', 'port'], False, 1, False], 'request': '/requests/1/0'}Failed
fixture 2{'decision': [True, None, [], False, False, True, ['host', 'scheme'], False, 0, False], 'request': '/requests/1/1'}{'decision': [True, None, [], False, False, True, ['scheme', 'host'], False, 0, False], 'request': '/requests/1/1'}Failed
fixture 3{'decision': [True, None, [], False, False, False, [], True, 0, True], 'request': '/requests/1/2'}{'decision': [True, None, [], False, False, False, [], True, 0, True], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [False, 'host', ['host', 'port'], True, True, False, ['port', 'host'], True, 2, False], 'request': '/requests/1/3'}{'decision': [False, 'host', ['host', 'port'], True, True, False, ['host', 'port'], True, 2, False], 'request': '/requests/1/3'}Failed
fixture 5{'decision': [True, None, [], False, False, False, ['scheme'], False, 0, False], 'request': '/requests/1/4'}{'decision': [True, None, [], False, False, False, ['scheme'], False, 0, False], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [False, 'scheme', ['scheme'], False, True, True, ['host', 'scheme'], True, 1, False], 'request': '/requests/1/5'}{'decision': [False, 'scheme', ['scheme'], False, True, True, ['scheme', 'host'], True, 1, False], 'request': '/requests/1/5'}Failed
fixture 7{'decision': [True, None, [], True, True, False, ['x'], False, 0, True], 'request': '/requests/1/6'}{'decision': [True, None, [], True, True, False, ['x'], False, 0, True], 'request': '/requests/1/6'}Passed

SHA-256 / 13c30e18f3d8c8485c0c53a8327d5268a4513c718c02d5160ba677ca2447943d

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
from urllib.parse import urlsplit, unquote, quote
import posixpath
import re
N = 1
observations = []
def solve(request, decisions, mode, inspected, override, target):
    return {'request': request, 'decision': [all(v for k,v in decisions), next((k for k,v in decisions if not v),None), [k for k,v in decisions if not v], mode == 'follow' and inspected, override and mode != 'error', mode == 'manual', [k for k,v in decisions], target is not None and override, sum(not v for k,v in decisions), inspected and all(v for k,v in decisions)]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', [['scheme', True], ['host', False], ['port', True]], 'follow', True, False, '/b'), {'request': '/requests/' + str(N) + '/0', 'decision': [False, 'host', ['host'], True, False, False, ['scheme', 'host', 'port'], False, 1, False]})
check('fixture 2', solve('/requests/' + str(N) + '/1', [['scheme', True], ['host', True]], 'manual', False, False, '/c'), {'request': '/requests/' + str(N) + '/1', 'decision': [True, None, [], False, False, True, ['scheme', 'host'], False, 0, False]})
check('fixture 3', solve('/requests/' + str(N) + '/2', [], 'error', True, True, '/d'), {'request': '/requests/' + str(N) + '/2', 'decision': [True, None, [], False, False, False, [], True, 0, True]})
check('fixture 4', solve('/requests/' + str(N) + '/3', [['host', False], ['port', False]], 'follow', True, True, '/e'), {'request': '/requests/' + str(N) + '/3', 'decision': [False, 'host', ['host', 'port'], True, True, False, ['host', 'port'], True, 2, False]})
check('fixture 5', solve('/requests/' + str(N) + '/4', [['scheme', True]], 'follow', False, False, None), {'request': '/requests/' + str(N) + '/4', 'decision': [True, None, [], False, False, False, ['scheme'], False, 0, False]})
check('fixture 6', solve('/requests/' + str(N) + '/5', [['scheme', False], ['host', True]], 'manual', True, True, '/f'), {'request': '/requests/' + str(N) + '/5', 'decision': [False, 'scheme', ['scheme'], False, True, True, ['scheme', 'host'], True, 1, False]})
check('fixture 7', solve('/requests/' + str(N) + '/6', [['x', True]], 'follow', True, True, None), {'request': '/requests/' + str(N) + '/6', 'decision': [True, None, [], True, True, False, ['x'], False, 0, True]})
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 1{'decision': [False, 'host', ['host'], True, False, False, ['scheme', 'host', 'port'], False, 1, False], 'request': '/requests/1/0'}{'decision': [False, 'host', ['host'], True, False, False, ['scheme', 'host', 'port'], False, 1, False], 'request': '/requests/1/0'}Passed
fixture 2{'decision': [True, None, [], False, False, True, ['scheme', 'host'], False, 0, False], 'request': '/requests/1/1'}{'decision': [True, None, [], False, False, True, ['scheme', 'host'], False, 0, False], 'request': '/requests/1/1'}Passed
fixture 3{'decision': [True, None, [], False, False, False, [], True, 0, True], 'request': '/requests/1/2'}{'decision': [True, None, [], False, False, False, [], True, 0, True], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [False, 'host', ['host', 'port'], True, True, False, ['host', 'port'], True, 2, False], 'request': '/requests/1/3'}{'decision': [False, 'host', ['host', 'port'], True, True, False, ['host', 'port'], True, 2, False], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [True, None, [], False, False, False, ['scheme'], False, 0, False], 'request': '/requests/1/4'}{'decision': [True, None, [], False, False, False, ['scheme'], False, 0, False], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [False, 'scheme', ['scheme'], False, True, True, ['scheme', 'host'], True, 1, False], 'request': '/requests/1/5'}{'decision': [False, 'scheme', ['scheme'], False, True, True, ['scheme', 'host'], True, 1, False], 'request': '/requests/1/5'}Passed
fixture 7{'decision': [True, None, [], True, True, False, ['x'], False, 0, True], 'request': '/requests/1/6'}{'decision': [True, None, [], True, True, False, ['x'], False, 0, True], 'request': '/requests/1/6'}Passed

SHA-256 / fb563b1f5f08ef10911f65f17f57dbebd0f4556acb5033f9c14fe03e177e65e1

Verification & scope

Stipulated offline redirect policy, not a complete HTTP, browser, URL, cache, or security implementation. Numbered variants vary request correlation identity. 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 2026-09-29T14:41:41.065001+00:00.

Case digest / f1aac2d77806e762b39e9943ff0d8d60affce57060398c229ad1882e6dae7026