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FA-28121 / HTTP redirects / Open access

Expose redirect events in request order without false completion: completion after cancel · case 01

Expose redirect events in request order without false completion: the completion after cancel branch emits an incorrect decision.

Verified by executionVariant 1 · 6 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The completion-after-cancel decision uses 'done'; this violates the stipulated controller policy.

VERIFIED REPAIR

At this decision use 'done and not canceled', preserving the other controller outputs.

Unsuccessful approach: The partial repair uses 'not canceled' and still fails an explicit boundary or control.

Case contract

Expose redirect events in request order without false completion. 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, events, accepted, target, done, canceled):
    return {'request': request, 'decision': [events + ([target] if accepted else []), done, len(events), events[-1] if events else None, 'canceled' if canceled else ('redirect' if accepted else 'blocked')]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', ['/a', '/b', '/a'], False, '/c', True, True), {'request': '/requests/' + str(N) + '/0', 'decision': [['/a', '/b', '/a'], False, 3, '/a', 'canceled']})
check('fixture 2', solve('/requests/' + str(N) + '/1', ['/a', '/b'], True, '/c', False, False), {'request': '/requests/' + str(N) + '/1', 'decision': [['/a', '/b', '/c'], False, 2, '/b', 'redirect']})
check('fixture 3', solve('/requests/' + str(N) + '/2', [], False, '/a', True, False), {'request': '/requests/' + str(N) + '/2', 'decision': [[], True, 0, None, 'blocked']})
check('fixture 4', solve('/requests/' + str(N) + '/3', [], True, '/a', False, False), {'request': '/requests/' + str(N) + '/3', 'decision': [['/a'], False, 0, None, 'redirect']})
check('fixture 5', solve('/requests/' + str(N) + '/4', ['/b'], True, '/c', True, True), {'request': '/requests/' + str(N) + '/4', 'decision': [['/b', '/c'], False, 1, '/b', 'canceled']})
check('fixture 6', solve('/requests/' + str(N) + '/5', ['/a', '/b'], False, '/c', False, False), {'request': '/requests/' + str(N) + '/5', 'decision': [['/a', '/b'], False, 2, '/b', 'blocked']})
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': [['/a', '/b', '/a'], True, 3, '/a', 'canceled'], 'request': '/requests/1/0'}{'decision': [['/a', '/b', '/a'], False, 3, '/a', 'canceled'], 'request': '/requests/1/0'}Failed
fixture 2{'decision': [['/a', '/b', '/c'], False, 2, '/b', 'redirect'], 'request': '/requests/1/1'}{'decision': [['/a', '/b', '/c'], False, 2, '/b', 'redirect'], 'request': '/requests/1/1'}Passed
fixture 3{'decision': [[], True, 0, None, 'blocked'], 'request': '/requests/1/2'}{'decision': [[], True, 0, None, 'blocked'], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [['/a'], False, 0, None, 'redirect'], 'request': '/requests/1/3'}{'decision': [['/a'], False, 0, None, 'redirect'], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [['/b', '/c'], True, 1, '/b', 'canceled'], 'request': '/requests/1/4'}{'decision': [['/b', '/c'], False, 1, '/b', 'canceled'], 'request': '/requests/1/4'}Failed
fixture 6{'decision': [['/a', '/b'], False, 2, '/b', 'blocked'], 'request': '/requests/1/5'}{'decision': [['/a', '/b'], False, 2, '/b', 'blocked'], 'request': '/requests/1/5'}Passed

SHA-256 / bfb41729c783ed5dd744d767844406f0414734ee59580da56eee85780675ac97

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, events, accepted, target, done, canceled):
    return {'request': request, 'decision': [events + ([target] if accepted else []), not canceled, len(events), events[-1] if events else None, 'canceled' if canceled else ('redirect' if accepted else 'blocked')]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', ['/a', '/b', '/a'], False, '/c', True, True), {'request': '/requests/' + str(N) + '/0', 'decision': [['/a', '/b', '/a'], False, 3, '/a', 'canceled']})
check('fixture 2', solve('/requests/' + str(N) + '/1', ['/a', '/b'], True, '/c', False, False), {'request': '/requests/' + str(N) + '/1', 'decision': [['/a', '/b', '/c'], False, 2, '/b', 'redirect']})
check('fixture 3', solve('/requests/' + str(N) + '/2', [], False, '/a', True, False), {'request': '/requests/' + str(N) + '/2', 'decision': [[], True, 0, None, 'blocked']})
check('fixture 4', solve('/requests/' + str(N) + '/3', [], True, '/a', False, False), {'request': '/requests/' + str(N) + '/3', 'decision': [['/a'], False, 0, None, 'redirect']})
check('fixture 5', solve('/requests/' + str(N) + '/4', ['/b'], True, '/c', True, True), {'request': '/requests/' + str(N) + '/4', 'decision': [['/b', '/c'], False, 1, '/b', 'canceled']})
check('fixture 6', solve('/requests/' + str(N) + '/5', ['/a', '/b'], False, '/c', False, False), {'request': '/requests/' + str(N) + '/5', 'decision': [['/a', '/b'], False, 2, '/b', 'blocked']})
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': [['/a', '/b', '/a'], False, 3, '/a', 'canceled'], 'request': '/requests/1/0'}{'decision': [['/a', '/b', '/a'], False, 3, '/a', 'canceled'], 'request': '/requests/1/0'}Passed
fixture 2{'decision': [['/a', '/b', '/c'], True, 2, '/b', 'redirect'], 'request': '/requests/1/1'}{'decision': [['/a', '/b', '/c'], False, 2, '/b', 'redirect'], 'request': '/requests/1/1'}Failed
fixture 3{'decision': [[], True, 0, None, 'blocked'], 'request': '/requests/1/2'}{'decision': [[], True, 0, None, 'blocked'], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [['/a'], True, 0, None, 'redirect'], 'request': '/requests/1/3'}{'decision': [['/a'], False, 0, None, 'redirect'], 'request': '/requests/1/3'}Failed
fixture 5{'decision': [['/b', '/c'], False, 1, '/b', 'canceled'], 'request': '/requests/1/4'}{'decision': [['/b', '/c'], False, 1, '/b', 'canceled'], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [['/a', '/b'], True, 2, '/b', 'blocked'], 'request': '/requests/1/5'}{'decision': [['/a', '/b'], False, 2, '/b', 'blocked'], 'request': '/requests/1/5'}Failed

SHA-256 / 6ea2829cd51b4af23507e86c44ca04a66b3984cfb36f71050e742c5745c9c575

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, events, accepted, target, done, canceled):
    return {'request': request, 'decision': [events + ([target] if accepted else []), done and not canceled, len(events), events[-1] if events else None, 'canceled' if canceled else ('redirect' if accepted else 'blocked')]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', ['/a', '/b', '/a'], False, '/c', True, True), {'request': '/requests/' + str(N) + '/0', 'decision': [['/a', '/b', '/a'], False, 3, '/a', 'canceled']})
check('fixture 2', solve('/requests/' + str(N) + '/1', ['/a', '/b'], True, '/c', False, False), {'request': '/requests/' + str(N) + '/1', 'decision': [['/a', '/b', '/c'], False, 2, '/b', 'redirect']})
check('fixture 3', solve('/requests/' + str(N) + '/2', [], False, '/a', True, False), {'request': '/requests/' + str(N) + '/2', 'decision': [[], True, 0, None, 'blocked']})
check('fixture 4', solve('/requests/' + str(N) + '/3', [], True, '/a', False, False), {'request': '/requests/' + str(N) + '/3', 'decision': [['/a'], False, 0, None, 'redirect']})
check('fixture 5', solve('/requests/' + str(N) + '/4', ['/b'], True, '/c', True, True), {'request': '/requests/' + str(N) + '/4', 'decision': [['/b', '/c'], False, 1, '/b', 'canceled']})
check('fixture 6', solve('/requests/' + str(N) + '/5', ['/a', '/b'], False, '/c', False, False), {'request': '/requests/' + str(N) + '/5', 'decision': [['/a', '/b'], False, 2, '/b', 'blocked']})
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': [['/a', '/b', '/a'], False, 3, '/a', 'canceled'], 'request': '/requests/1/0'}{'decision': [['/a', '/b', '/a'], False, 3, '/a', 'canceled'], 'request': '/requests/1/0'}Passed
fixture 2{'decision': [['/a', '/b', '/c'], False, 2, '/b', 'redirect'], 'request': '/requests/1/1'}{'decision': [['/a', '/b', '/c'], False, 2, '/b', 'redirect'], 'request': '/requests/1/1'}Passed
fixture 3{'decision': [[], True, 0, None, 'blocked'], 'request': '/requests/1/2'}{'decision': [[], True, 0, None, 'blocked'], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [['/a'], False, 0, None, 'redirect'], 'request': '/requests/1/3'}{'decision': [['/a'], False, 0, None, 'redirect'], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [['/b', '/c'], False, 1, '/b', 'canceled'], 'request': '/requests/1/4'}{'decision': [['/b', '/c'], False, 1, '/b', 'canceled'], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [['/a', '/b'], False, 2, '/b', 'blocked'], 'request': '/requests/1/5'}{'decision': [['/a', '/b'], False, 2, '/b', 'blocked'], 'request': '/requests/1/5'}Passed

SHA-256 / e8ee6c261d6c7a8f0f134377aa251974d311a013423f4c0df3ec6afd3cf9a18f

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 2026-09-29T14:41:31.134058+00:00.

Case digest / c7b733e3c92b19067a8e619a96448f0e76a498fcd549d2a94bc2997995883831