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FA-28251 / HTTP redirects / Open access

Build a bounded manual redirect result without issuing the next request: redirect error envelope · case 01

Build a bounded manual redirect result without issuing the next request: the redirect error envelope branch emits an incorrect decision.

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

ROOT CAUSE

The redirect-error-envelope decision uses "mode == 'error'"; this violates the stipulated controller policy.

VERIFIED REPAIR

At this decision use "mode == 'error' and location is not None", preserving the other controller outputs.

Unsuccessful approach: The partial repair uses "mode != 'follow'" and still fails an explicit boundary or control.

Case contract

Build a bounded manual redirect result without issuing the next request. 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, mode, location, exposed, origin, body, status):
    return {'request': request, 'decision': [location if exposed else None, mode == 'follow' and location is not None, mode == 'error', status if exposed else 0, body if exposed else '', 'manual-redirect' if mode == 'manual' and location is not None else 'response', exposed and origin == 'same', exposed and mode != 'error', location is not None, status//100]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', 'manual', '/b', True, 'same', 'abc', 302), {'request': '/requests/' + str(N) + '/0', 'decision': ['/b', False, False, 302, 'abc', 'manual-redirect', True, True, True, 3]})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'follow', '', True, 'cross', 'read', 307), {'request': '/requests/' + str(N) + '/1', 'decision': ['', True, False, 307, 'read', 'response', False, True, True, 3]})
check('fixture 3', solve('/requests/' + str(N) + '/2', 'error', '/d', True, 'same', 'err', 301), {'request': '/requests/' + str(N) + '/2', 'decision': ['/d', False, True, 301, 'err', 'response', True, False, True, 3]})
check('fixture 4', solve('/requests/' + str(N) + '/3', 'manual', '/e', False, 'same', 'abc', 303), {'request': '/requests/' + str(N) + '/3', 'decision': [None, False, False, 0, '', 'manual-redirect', False, False, True, 3]})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'error', None, True, 'same', '', 200), {'request': '/requests/' + str(N) + '/4', 'decision': [None, False, False, 200, '', 'response', True, False, False, 2]})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'follow', None, False, 'cross', 'body', 404), {'request': '/requests/' + str(N) + '/5', 'decision': [None, False, False, 0, '', 'response', False, False, False, 4]})
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': ['/b', False, False, 302, 'abc', 'manual-redirect', True, True, True, 3], 'request': '/requests/1/0'}{'decision': ['/b', False, False, 302, 'abc', 'manual-redirect', True, True, True, 3], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['', True, False, 307, 'read', 'response', False, True, True, 3], 'request': '/requests/1/1'}{'decision': ['', True, False, 307, 'read', 'response', False, True, True, 3], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['/d', False, True, 301, 'err', 'response', True, False, True, 3], 'request': '/requests/1/2'}{'decision': ['/d', False, True, 301, 'err', 'response', True, False, True, 3], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [None, False, False, 0, '', 'manual-redirect', False, False, True, 3], 'request': '/requests/1/3'}{'decision': [None, False, False, 0, '', 'manual-redirect', False, False, True, 3], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [None, False, True, 200, '', 'response', True, False, False, 2], 'request': '/requests/1/4'}{'decision': [None, False, False, 200, '', 'response', True, False, False, 2], 'request': '/requests/1/4'}Failed
fixture 6{'decision': [None, False, False, 0, '', 'response', False, False, False, 4], 'request': '/requests/1/5'}{'decision': [None, False, False, 0, '', 'response', False, False, False, 4], 'request': '/requests/1/5'}Passed

SHA-256 / 3c4aaebb2ed4dfa850443ee0c334163c6ab77d13dee38b4d8d6e11c5b00c01ea

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, mode, location, exposed, origin, body, status):
    return {'request': request, 'decision': [location if exposed else None, mode == 'follow' and location is not None, mode != 'follow', status if exposed else 0, body if exposed else '', 'manual-redirect' if mode == 'manual' and location is not None else 'response', exposed and origin == 'same', exposed and mode != 'error', location is not None, status//100]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', 'manual', '/b', True, 'same', 'abc', 302), {'request': '/requests/' + str(N) + '/0', 'decision': ['/b', False, False, 302, 'abc', 'manual-redirect', True, True, True, 3]})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'follow', '', True, 'cross', 'read', 307), {'request': '/requests/' + str(N) + '/1', 'decision': ['', True, False, 307, 'read', 'response', False, True, True, 3]})
check('fixture 3', solve('/requests/' + str(N) + '/2', 'error', '/d', True, 'same', 'err', 301), {'request': '/requests/' + str(N) + '/2', 'decision': ['/d', False, True, 301, 'err', 'response', True, False, True, 3]})
check('fixture 4', solve('/requests/' + str(N) + '/3', 'manual', '/e', False, 'same', 'abc', 303), {'request': '/requests/' + str(N) + '/3', 'decision': [None, False, False, 0, '', 'manual-redirect', False, False, True, 3]})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'error', None, True, 'same', '', 200), {'request': '/requests/' + str(N) + '/4', 'decision': [None, False, False, 200, '', 'response', True, False, False, 2]})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'follow', None, False, 'cross', 'body', 404), {'request': '/requests/' + str(N) + '/5', 'decision': [None, False, False, 0, '', 'response', False, False, False, 4]})
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': ['/b', False, True, 302, 'abc', 'manual-redirect', True, True, True, 3], 'request': '/requests/1/0'}{'decision': ['/b', False, False, 302, 'abc', 'manual-redirect', True, True, True, 3], 'request': '/requests/1/0'}Failed
fixture 2{'decision': ['', True, False, 307, 'read', 'response', False, True, True, 3], 'request': '/requests/1/1'}{'decision': ['', True, False, 307, 'read', 'response', False, True, True, 3], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['/d', False, True, 301, 'err', 'response', True, False, True, 3], 'request': '/requests/1/2'}{'decision': ['/d', False, True, 301, 'err', 'response', True, False, True, 3], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [None, False, True, 0, '', 'manual-redirect', False, False, True, 3], 'request': '/requests/1/3'}{'decision': [None, False, False, 0, '', 'manual-redirect', False, False, True, 3], 'request': '/requests/1/3'}Failed
fixture 5{'decision': [None, False, True, 200, '', 'response', True, False, False, 2], 'request': '/requests/1/4'}{'decision': [None, False, False, 200, '', 'response', True, False, False, 2], 'request': '/requests/1/4'}Failed
fixture 6{'decision': [None, False, False, 0, '', 'response', False, False, False, 4], 'request': '/requests/1/5'}{'decision': [None, False, False, 0, '', 'response', False, False, False, 4], 'request': '/requests/1/5'}Passed

SHA-256 / 01fe298cb64bea60ef9a43b71c18a2bfd0958c2b36dd95d4ea8004e51ca160ae

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, mode, location, exposed, origin, body, status):
    return {'request': request, 'decision': [location if exposed else None, mode == 'follow' and location is not None, mode == 'error' and location is not None, status if exposed else 0, body if exposed else '', 'manual-redirect' if mode == 'manual' and location is not None else 'response', exposed and origin == 'same', exposed and mode != 'error', location is not None, status//100]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', 'manual', '/b', True, 'same', 'abc', 302), {'request': '/requests/' + str(N) + '/0', 'decision': ['/b', False, False, 302, 'abc', 'manual-redirect', True, True, True, 3]})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'follow', '', True, 'cross', 'read', 307), {'request': '/requests/' + str(N) + '/1', 'decision': ['', True, False, 307, 'read', 'response', False, True, True, 3]})
check('fixture 3', solve('/requests/' + str(N) + '/2', 'error', '/d', True, 'same', 'err', 301), {'request': '/requests/' + str(N) + '/2', 'decision': ['/d', False, True, 301, 'err', 'response', True, False, True, 3]})
check('fixture 4', solve('/requests/' + str(N) + '/3', 'manual', '/e', False, 'same', 'abc', 303), {'request': '/requests/' + str(N) + '/3', 'decision': [None, False, False, 0, '', 'manual-redirect', False, False, True, 3]})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'error', None, True, 'same', '', 200), {'request': '/requests/' + str(N) + '/4', 'decision': [None, False, False, 200, '', 'response', True, False, False, 2]})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'follow', None, False, 'cross', 'body', 404), {'request': '/requests/' + str(N) + '/5', 'decision': [None, False, False, 0, '', 'response', False, False, False, 4]})
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': ['/b', False, False, 302, 'abc', 'manual-redirect', True, True, True, 3], 'request': '/requests/1/0'}{'decision': ['/b', False, False, 302, 'abc', 'manual-redirect', True, True, True, 3], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['', True, False, 307, 'read', 'response', False, True, True, 3], 'request': '/requests/1/1'}{'decision': ['', True, False, 307, 'read', 'response', False, True, True, 3], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['/d', False, True, 301, 'err', 'response', True, False, True, 3], 'request': '/requests/1/2'}{'decision': ['/d', False, True, 301, 'err', 'response', True, False, True, 3], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [None, False, False, 0, '', 'manual-redirect', False, False, True, 3], 'request': '/requests/1/3'}{'decision': [None, False, False, 0, '', 'manual-redirect', False, False, True, 3], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [None, False, False, 200, '', 'response', True, False, False, 2], 'request': '/requests/1/4'}{'decision': [None, False, False, 200, '', 'response', True, False, False, 2], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [None, False, False, 0, '', 'response', False, False, False, 4], 'request': '/requests/1/5'}{'decision': [None, False, False, 0, '', 'response', False, False, False, 4], 'request': '/requests/1/5'}Passed

SHA-256 / b42defa6f1a7d6ea5f11be4b432f1c56c5a70f68b7b623c92ae1cab3cc5573f8

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 2026-09-29T14:41:32.287195+00:00.

Case digest / 16554db90b1e110a6b6a0ab4e64bf6eb84e41d6fd0294bb6367ca0fe67d6514e