FAILURE MAP
← Case archive

FA-27926 / HTTP redirects / Open access

Apply a configured HTTP redirect scheme policy: non network rejection · case 01

Non-network targets are not consistently rejected.

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

ROOT CAUSE

The non-network-rejection decision uses "scheme.lower() == 'file'"; this violates the stipulated controller policy.

VERIFIED REPAIR

At this decision use "scheme.lower() not in ('', 'http', 'https')", preserving the other controller outputs.

Unsuccessful approach: The partial repair uses "scheme.lower() not in ('http','https')" and still fails an explicit boundary or control.

Case contract

Apply a configured HTTP redirect scheme policy. 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, scheme, source, explicit, upgrades, allow_relative):
    return {'request': request, 'decision': [scheme.lower(), bool(scheme) or allow_relative, scheme.lower() == 'file', source == 'http' and scheme.lower() == 'https', 'https' if not explicit and source in upgrades else source]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', 'HtTpS', 'http', False, ['http'], False), {'request': '/requests/' + str(N) + '/0', 'decision': ['https', True, False, True, 'https']})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'https', 'https', True, ['https'], True), {'request': '/requests/' + str(N) + '/1', 'decision': ['https', True, False, False, 'https']})
check('fixture 3', solve('/requests/' + str(N) + '/2', '', 'http', True, ['http'], True), {'request': '/requests/' + str(N) + '/2', 'decision': ['', True, False, False, 'http']})
check('fixture 4', solve('/requests/' + str(N) + '/3', '', 'http', False, [], False), {'request': '/requests/' + str(N) + '/3', 'decision': ['', False, False, False, 'http']})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'data', 'https', True, [], True), {'request': '/requests/' + str(N) + '/4', 'decision': ['data', True, True, False, 'https']})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'http', 'https', False, [], False), {'request': '/requests/' + str(N) + '/5', 'decision': ['http', True, False, False, 'https']})
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': ['https', True, False, True, 'https'], 'request': '/requests/1/0'}{'decision': ['https', True, False, True, 'https'], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['https', True, False, False, 'https'], 'request': '/requests/1/1'}{'decision': ['https', True, False, False, 'https'], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['', True, False, False, 'http'], 'request': '/requests/1/2'}{'decision': ['', True, False, False, 'http'], 'request': '/requests/1/2'}Passed
fixture 4{'decision': ['', False, False, False, 'http'], 'request': '/requests/1/3'}{'decision': ['', False, False, False, 'http'], 'request': '/requests/1/3'}Passed
fixture 5{'decision': ['data', True, False, False, 'https'], 'request': '/requests/1/4'}{'decision': ['data', True, True, False, 'https'], 'request': '/requests/1/4'}Failed
fixture 6{'decision': ['http', True, False, False, 'https'], 'request': '/requests/1/5'}{'decision': ['http', True, False, False, 'https'], 'request': '/requests/1/5'}Passed

SHA-256 / 67a7bc96e8b41b92ee0ca3585c1d846c0ebf4f40a8e6f75364b88091b3ba470d

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, scheme, source, explicit, upgrades, allow_relative):
    return {'request': request, 'decision': [scheme.lower(), bool(scheme) or allow_relative, scheme.lower() not in ('http','https'), source == 'http' and scheme.lower() == 'https', 'https' if not explicit and source in upgrades else source]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', 'HtTpS', 'http', False, ['http'], False), {'request': '/requests/' + str(N) + '/0', 'decision': ['https', True, False, True, 'https']})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'https', 'https', True, ['https'], True), {'request': '/requests/' + str(N) + '/1', 'decision': ['https', True, False, False, 'https']})
check('fixture 3', solve('/requests/' + str(N) + '/2', '', 'http', True, ['http'], True), {'request': '/requests/' + str(N) + '/2', 'decision': ['', True, False, False, 'http']})
check('fixture 4', solve('/requests/' + str(N) + '/3', '', 'http', False, [], False), {'request': '/requests/' + str(N) + '/3', 'decision': ['', False, False, False, 'http']})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'data', 'https', True, [], True), {'request': '/requests/' + str(N) + '/4', 'decision': ['data', True, True, False, 'https']})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'http', 'https', False, [], False), {'request': '/requests/' + str(N) + '/5', 'decision': ['http', True, False, False, 'https']})
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': ['https', True, False, True, 'https'], 'request': '/requests/1/0'}{'decision': ['https', True, False, True, 'https'], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['https', True, False, False, 'https'], 'request': '/requests/1/1'}{'decision': ['https', True, False, False, 'https'], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['', True, True, False, 'http'], 'request': '/requests/1/2'}{'decision': ['', True, False, False, 'http'], 'request': '/requests/1/2'}Failed
fixture 4{'decision': ['', False, True, False, 'http'], 'request': '/requests/1/3'}{'decision': ['', False, False, False, 'http'], 'request': '/requests/1/3'}Failed
fixture 5{'decision': ['data', True, True, False, 'https'], 'request': '/requests/1/4'}{'decision': ['data', True, True, False, 'https'], 'request': '/requests/1/4'}Passed
fixture 6{'decision': ['http', True, False, False, 'https'], 'request': '/requests/1/5'}{'decision': ['http', True, False, False, 'https'], 'request': '/requests/1/5'}Passed

SHA-256 / f31c80aa1d9f05831fd44ea2f6ee479c513c87c031b59d52f65569ed617704ec

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, scheme, source, explicit, upgrades, allow_relative):
    return {'request': request, 'decision': [scheme.lower(), bool(scheme) or allow_relative, scheme.lower() not in ('', 'http', 'https'), source == 'http' and scheme.lower() == 'https', 'https' if not explicit and source in upgrades else source]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', 'HtTpS', 'http', False, ['http'], False), {'request': '/requests/' + str(N) + '/0', 'decision': ['https', True, False, True, 'https']})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'https', 'https', True, ['https'], True), {'request': '/requests/' + str(N) + '/1', 'decision': ['https', True, False, False, 'https']})
check('fixture 3', solve('/requests/' + str(N) + '/2', '', 'http', True, ['http'], True), {'request': '/requests/' + str(N) + '/2', 'decision': ['', True, False, False, 'http']})
check('fixture 4', solve('/requests/' + str(N) + '/3', '', 'http', False, [], False), {'request': '/requests/' + str(N) + '/3', 'decision': ['', False, False, False, 'http']})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'data', 'https', True, [], True), {'request': '/requests/' + str(N) + '/4', 'decision': ['data', True, True, False, 'https']})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'http', 'https', False, [], False), {'request': '/requests/' + str(N) + '/5', 'decision': ['http', True, False, False, 'https']})
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': ['https', True, False, True, 'https'], 'request': '/requests/1/0'}{'decision': ['https', True, False, True, 'https'], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['https', True, False, False, 'https'], 'request': '/requests/1/1'}{'decision': ['https', True, False, False, 'https'], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['', True, False, False, 'http'], 'request': '/requests/1/2'}{'decision': ['', True, False, False, 'http'], 'request': '/requests/1/2'}Passed
fixture 4{'decision': ['', False, False, False, 'http'], 'request': '/requests/1/3'}{'decision': ['', False, False, False, 'http'], 'request': '/requests/1/3'}Passed
fixture 5{'decision': ['data', True, True, False, 'https'], 'request': '/requests/1/4'}{'decision': ['data', True, True, False, 'https'], 'request': '/requests/1/4'}Passed
fixture 6{'decision': ['http', True, False, False, 'https'], 'request': '/requests/1/5'}{'decision': ['http', True, False, False, 'https'], 'request': '/requests/1/5'}Passed

SHA-256 / ec4cf6b864ac344ea50a600e5362cc8d34058c7436297913f4cf2a3c5f69ff28

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 2026-09-29T14:41:29.500146+00:00.

Case digest / 8b6a151ceb40d344eb94038b240754972df3c62af64f21c0c6d88c9196dd5498