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FA-29311 / HTTP redirects / Open access

Report redirect failures with the failing phase and completed request context: error code optional · case 01

Report redirect failures with the failing phase and completed request context: the error code optional branch emits an incorrect decision.

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

ROOT CAUSE

The error-code-optional decision uses "code or 'unknown'"; this violates the stipulated controller policy.

VERIFIED REPAIR

At this decision use "code if code is not None else 'none'", preserving the other controller outputs.

Unsuccessful approach: The partial repair uses "'blocked' if rejected else 'none'" and still fails an explicit boundary or control.

Case contract

Report redirect failures with the failing phase and completed request context. 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, phase, code, completed, attempted, rejected, original):
    return {'request': request, 'decision': [phase, original, attempted, completed, code or 'unknown', code is not None, completed[-1] if completed else None, phase in ('parse','policy'), completed, rejected or phase == 'parse']} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', 'parse', 'invalid-target', ['/a'], 'bad%', True, '/a'), {'request': '/requests/' + str(N) + '/0', 'decision': ['parse', '/a', 'bad%', ['/a'], 'invalid-target', True, '/a', True, ['/a'], True]})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'policy', 'blocked', ['/a', '/b'], '/c', True, '/a'), {'request': '/requests/' + str(N) + '/1', 'decision': ['policy', '/a', '/c', ['/a', '/b'], 'blocked', True, '/b', True, ['/a', '/b'], True]})
check('fixture 3', solve('/requests/' + str(N) + '/2', 'dispatch', 'closed', ['/a'], '/b', False, '/a'), {'request': '/requests/' + str(N) + '/2', 'decision': ['dispatch', '/a', '/b', ['/a'], 'closed', True, '/a', False, ['/a'], False]})
check('fixture 4', solve('/requests/' + str(N) + '/3', 'response', 'body-error', [], '/x', False, '/x'), {'request': '/requests/' + str(N) + '/3', 'decision': ['response', '/x', '/x', [], 'body-error', True, None, False, [], False]})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'complete', None, ['/a', '/b'], '/b', False, '/a'), {'request': '/requests/' + str(N) + '/4', 'decision': ['complete', '/a', '/b', ['/a', '/b'], 'none', False, '/b', False, ['/a', '/b'], False]})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'policy', 'blocked', [], '/x', True, '/x'), {'request': '/requests/' + str(N) + '/5', 'decision': ['policy', '/x', '/x', [], 'blocked', True, None, True, [], True]})
check('fixture 7', solve('/requests/' + str(N) + '/6', 'parse', 'invalid-target', ['/z', '/a'], 'bad%', False, '/z'), {'request': '/requests/' + str(N) + '/6', 'decision': ['parse', '/z', 'bad%', ['/z', '/a'], 'invalid-target', True, '/a', True, ['/z', '/a'], 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': ['parse', '/a', 'bad%', ['/a'], 'invalid-target', True, '/a', True, ['/a'], True], 'request': '/requests/1/0'}{'decision': ['parse', '/a', 'bad%', ['/a'], 'invalid-target', True, '/a', True, ['/a'], True], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['policy', '/a', '/c', ['/a', '/b'], 'blocked', True, '/b', True, ['/a', '/b'], True], 'request': '/requests/1/1'}{'decision': ['policy', '/a', '/c', ['/a', '/b'], 'blocked', True, '/b', True, ['/a', '/b'], True], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['dispatch', '/a', '/b', ['/a'], 'closed', True, '/a', False, ['/a'], False], 'request': '/requests/1/2'}{'decision': ['dispatch', '/a', '/b', ['/a'], 'closed', True, '/a', False, ['/a'], False], 'request': '/requests/1/2'}Passed
fixture 4{'decision': ['response', '/x', '/x', [], 'body-error', True, None, False, [], False], 'request': '/requests/1/3'}{'decision': ['response', '/x', '/x', [], 'body-error', True, None, False, [], False], 'request': '/requests/1/3'}Passed
fixture 5{'decision': ['complete', '/a', '/b', ['/a', '/b'], 'unknown', False, '/b', False, ['/a', '/b'], False], 'request': '/requests/1/4'}{'decision': ['complete', '/a', '/b', ['/a', '/b'], 'none', False, '/b', False, ['/a', '/b'], False], 'request': '/requests/1/4'}Failed
fixture 6{'decision': ['policy', '/x', '/x', [], 'blocked', True, None, True, [], True], 'request': '/requests/1/5'}{'decision': ['policy', '/x', '/x', [], 'blocked', True, None, True, [], True], 'request': '/requests/1/5'}Passed
fixture 7{'decision': ['parse', '/z', 'bad%', ['/z', '/a'], 'invalid-target', True, '/a', True, ['/z', '/a'], True], 'request': '/requests/1/6'}{'decision': ['parse', '/z', 'bad%', ['/z', '/a'], 'invalid-target', True, '/a', True, ['/z', '/a'], True], 'request': '/requests/1/6'}Passed

SHA-256 / b8643f78bd896b9cc5d452e2eda1f73916ee6aea780ee7ee8e43238e2fce5c6d

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, phase, code, completed, attempted, rejected, original):
    return {'request': request, 'decision': [phase, original, attempted, completed, 'blocked' if rejected else 'none', code is not None, completed[-1] if completed else None, phase in ('parse','policy'), completed, rejected or phase == 'parse']} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', 'parse', 'invalid-target', ['/a'], 'bad%', True, '/a'), {'request': '/requests/' + str(N) + '/0', 'decision': ['parse', '/a', 'bad%', ['/a'], 'invalid-target', True, '/a', True, ['/a'], True]})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'policy', 'blocked', ['/a', '/b'], '/c', True, '/a'), {'request': '/requests/' + str(N) + '/1', 'decision': ['policy', '/a', '/c', ['/a', '/b'], 'blocked', True, '/b', True, ['/a', '/b'], True]})
check('fixture 3', solve('/requests/' + str(N) + '/2', 'dispatch', 'closed', ['/a'], '/b', False, '/a'), {'request': '/requests/' + str(N) + '/2', 'decision': ['dispatch', '/a', '/b', ['/a'], 'closed', True, '/a', False, ['/a'], False]})
check('fixture 4', solve('/requests/' + str(N) + '/3', 'response', 'body-error', [], '/x', False, '/x'), {'request': '/requests/' + str(N) + '/3', 'decision': ['response', '/x', '/x', [], 'body-error', True, None, False, [], False]})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'complete', None, ['/a', '/b'], '/b', False, '/a'), {'request': '/requests/' + str(N) + '/4', 'decision': ['complete', '/a', '/b', ['/a', '/b'], 'none', False, '/b', False, ['/a', '/b'], False]})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'policy', 'blocked', [], '/x', True, '/x'), {'request': '/requests/' + str(N) + '/5', 'decision': ['policy', '/x', '/x', [], 'blocked', True, None, True, [], True]})
check('fixture 7', solve('/requests/' + str(N) + '/6', 'parse', 'invalid-target', ['/z', '/a'], 'bad%', False, '/z'), {'request': '/requests/' + str(N) + '/6', 'decision': ['parse', '/z', 'bad%', ['/z', '/a'], 'invalid-target', True, '/a', True, ['/z', '/a'], 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': ['parse', '/a', 'bad%', ['/a'], 'blocked', True, '/a', True, ['/a'], True], 'request': '/requests/1/0'}{'decision': ['parse', '/a', 'bad%', ['/a'], 'invalid-target', True, '/a', True, ['/a'], True], 'request': '/requests/1/0'}Failed
fixture 2{'decision': ['policy', '/a', '/c', ['/a', '/b'], 'blocked', True, '/b', True, ['/a', '/b'], True], 'request': '/requests/1/1'}{'decision': ['policy', '/a', '/c', ['/a', '/b'], 'blocked', True, '/b', True, ['/a', '/b'], True], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['dispatch', '/a', '/b', ['/a'], 'none', True, '/a', False, ['/a'], False], 'request': '/requests/1/2'}{'decision': ['dispatch', '/a', '/b', ['/a'], 'closed', True, '/a', False, ['/a'], False], 'request': '/requests/1/2'}Failed
fixture 4{'decision': ['response', '/x', '/x', [], 'none', True, None, False, [], False], 'request': '/requests/1/3'}{'decision': ['response', '/x', '/x', [], 'body-error', True, None, False, [], False], 'request': '/requests/1/3'}Failed
fixture 5{'decision': ['complete', '/a', '/b', ['/a', '/b'], 'none', False, '/b', False, ['/a', '/b'], False], 'request': '/requests/1/4'}{'decision': ['complete', '/a', '/b', ['/a', '/b'], 'none', False, '/b', False, ['/a', '/b'], False], 'request': '/requests/1/4'}Passed
fixture 6{'decision': ['policy', '/x', '/x', [], 'blocked', True, None, True, [], True], 'request': '/requests/1/5'}{'decision': ['policy', '/x', '/x', [], 'blocked', True, None, True, [], True], 'request': '/requests/1/5'}Passed
fixture 7{'decision': ['parse', '/z', 'bad%', ['/z', '/a'], 'none', True, '/a', True, ['/z', '/a'], True], 'request': '/requests/1/6'}{'decision': ['parse', '/z', 'bad%', ['/z', '/a'], 'invalid-target', True, '/a', True, ['/z', '/a'], True], 'request': '/requests/1/6'}Failed

SHA-256 / 9816e24a66ed9e1b11bee75cc54904d7bbf2b0a1655c7e4fb53543103cf549da

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, phase, code, completed, attempted, rejected, original):
    return {'request': request, 'decision': [phase, original, attempted, completed, code if code is not None else 'none', code is not None, completed[-1] if completed else None, phase in ('parse','policy'), completed, rejected or phase == 'parse']} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', 'parse', 'invalid-target', ['/a'], 'bad%', True, '/a'), {'request': '/requests/' + str(N) + '/0', 'decision': ['parse', '/a', 'bad%', ['/a'], 'invalid-target', True, '/a', True, ['/a'], True]})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'policy', 'blocked', ['/a', '/b'], '/c', True, '/a'), {'request': '/requests/' + str(N) + '/1', 'decision': ['policy', '/a', '/c', ['/a', '/b'], 'blocked', True, '/b', True, ['/a', '/b'], True]})
check('fixture 3', solve('/requests/' + str(N) + '/2', 'dispatch', 'closed', ['/a'], '/b', False, '/a'), {'request': '/requests/' + str(N) + '/2', 'decision': ['dispatch', '/a', '/b', ['/a'], 'closed', True, '/a', False, ['/a'], False]})
check('fixture 4', solve('/requests/' + str(N) + '/3', 'response', 'body-error', [], '/x', False, '/x'), {'request': '/requests/' + str(N) + '/3', 'decision': ['response', '/x', '/x', [], 'body-error', True, None, False, [], False]})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'complete', None, ['/a', '/b'], '/b', False, '/a'), {'request': '/requests/' + str(N) + '/4', 'decision': ['complete', '/a', '/b', ['/a', '/b'], 'none', False, '/b', False, ['/a', '/b'], False]})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'policy', 'blocked', [], '/x', True, '/x'), {'request': '/requests/' + str(N) + '/5', 'decision': ['policy', '/x', '/x', [], 'blocked', True, None, True, [], True]})
check('fixture 7', solve('/requests/' + str(N) + '/6', 'parse', 'invalid-target', ['/z', '/a'], 'bad%', False, '/z'), {'request': '/requests/' + str(N) + '/6', 'decision': ['parse', '/z', 'bad%', ['/z', '/a'], 'invalid-target', True, '/a', True, ['/z', '/a'], 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': ['parse', '/a', 'bad%', ['/a'], 'invalid-target', True, '/a', True, ['/a'], True], 'request': '/requests/1/0'}{'decision': ['parse', '/a', 'bad%', ['/a'], 'invalid-target', True, '/a', True, ['/a'], True], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['policy', '/a', '/c', ['/a', '/b'], 'blocked', True, '/b', True, ['/a', '/b'], True], 'request': '/requests/1/1'}{'decision': ['policy', '/a', '/c', ['/a', '/b'], 'blocked', True, '/b', True, ['/a', '/b'], True], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['dispatch', '/a', '/b', ['/a'], 'closed', True, '/a', False, ['/a'], False], 'request': '/requests/1/2'}{'decision': ['dispatch', '/a', '/b', ['/a'], 'closed', True, '/a', False, ['/a'], False], 'request': '/requests/1/2'}Passed
fixture 4{'decision': ['response', '/x', '/x', [], 'body-error', True, None, False, [], False], 'request': '/requests/1/3'}{'decision': ['response', '/x', '/x', [], 'body-error', True, None, False, [], False], 'request': '/requests/1/3'}Passed
fixture 5{'decision': ['complete', '/a', '/b', ['/a', '/b'], 'none', False, '/b', False, ['/a', '/b'], False], 'request': '/requests/1/4'}{'decision': ['complete', '/a', '/b', ['/a', '/b'], 'none', False, '/b', False, ['/a', '/b'], False], 'request': '/requests/1/4'}Passed
fixture 6{'decision': ['policy', '/x', '/x', [], 'blocked', True, None, True, [], True], 'request': '/requests/1/5'}{'decision': ['policy', '/x', '/x', [], 'blocked', True, None, True, [], True], 'request': '/requests/1/5'}Passed
fixture 7{'decision': ['parse', '/z', 'bad%', ['/z', '/a'], 'invalid-target', True, '/a', True, ['/z', '/a'], True], 'request': '/requests/1/6'}{'decision': ['parse', '/z', 'bad%', ['/z', '/a'], 'invalid-target', True, '/a', True, ['/z', '/a'], True], 'request': '/requests/1/6'}Passed

SHA-256 / 57c5841b0a92b1cfb17b555fae4303a39a42f0f62f8c1cb839e48c41e6f3e6fc

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 2026-09-29T14:41:42.015243+00:00.

Case digest / 5829ea7ee09ccc312ba3f2adb60298ade9fbfdb315fe36b9862ac8f87d73fe29