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FA-28371 / HTTP redirects / Open access

Partition redirect cache entries by their declared request dimensions: empty value query presence · case 01

Partition redirect cache entries by their declared request dimensions: the empty value query presence branch emits an incorrect decision.

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

ROOT CAUSE

The empty-value-query-presence decision uses 'bool(query)'; this violates the stipulated controller policy.

VERIFIED REPAIR

At this decision use "'=' in query", preserving the other controller outputs.

Unsuccessful approach: The partial repair uses "bool(query.partition('=')[2])" and still fails an explicit boundary or control.

Case contract

Partition redirect cache entries by their declared request dimensions. 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, host, port, method, path, query, partition, vary):
    return {'request': request, 'decision': [scheme, host.lower(), None if (scheme,port) in (("https",443),("http",80)) else port, method, path, query, bool(query), partition, vary, len(vary)]} 
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', 'H.TEST', 443, 'GET', '/A', 'x=1', 'tab1', ['en', 'gzip']), {'request': '/requests/' + str(N) + '/0', 'decision': ['https', 'h.test', None, 'GET', '/A', 'x=1', True, 'tab1', ['en', 'gzip'], 2]})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'https', 'h.test', 8443, 'HEAD', '/a', 'x=2', 'tab2', ['fr', 'br']), {'request': '/requests/' + str(N) + '/1', 'decision': ['https', 'h.test', 8443, 'HEAD', '/a', 'x=2', True, 'tab2', ['fr', 'br'], 2]})
check('fixture 3', solve('/requests/' + str(N) + '/2', 'http', 'h.test', 80, 'POST', '/a', 'q=', 'tab1', []), {'request': '/requests/' + str(N) + '/2', 'decision': ['http', 'h.test', None, 'POST', '/a', 'q=', True, 'tab1', [], 0]})
check('fixture 4', solve('/requests/' + str(N) + '/3', 'http', 'Z.TEST', 8080, 'GET', '/b', 'b=2&a=1&b=2', 'tab3', ['en', 'br']), {'request': '/requests/' + str(N) + '/3', 'decision': ['http', 'z.test', 8080, 'GET', '/b', 'b=2&a=1&b=2', True, 'tab3', ['en', 'br'], 2]})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'https', 'h.test', 443, 'PUT', '/B', 'flag', 'tab2', ['']), {'request': '/requests/' + str(N) + '/4', 'decision': ['https', 'h.test', None, 'PUT', '/B', 'flag', False, 'tab2', [''], 1]})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'https', 'h.test', 443, 'GET', '/a', 'x=1', 'tab1', ['gzip', 'en', 'gzip']), {'request': '/requests/' + str(N) + '/5', 'decision': ['https', 'h.test', None, 'GET', '/a', 'x=1', True, 'tab1', ['gzip', 'en', 'gzip'], 3]})
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', 'h.test', None, 'GET', '/A', 'x=1', True, 'tab1', ['en', 'gzip'], 2], 'request': '/requests/1/0'}{'decision': ['https', 'h.test', None, 'GET', '/A', 'x=1', True, 'tab1', ['en', 'gzip'], 2], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['https', 'h.test', 8443, 'HEAD', '/a', 'x=2', True, 'tab2', ['fr', 'br'], 2], 'request': '/requests/1/1'}{'decision': ['https', 'h.test', 8443, 'HEAD', '/a', 'x=2', True, 'tab2', ['fr', 'br'], 2], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['http', 'h.test', None, 'POST', '/a', 'q=', True, 'tab1', [], 0], 'request': '/requests/1/2'}{'decision': ['http', 'h.test', None, 'POST', '/a', 'q=', True, 'tab1', [], 0], 'request': '/requests/1/2'}Passed
fixture 4{'decision': ['http', 'z.test', 8080, 'GET', '/b', 'b=2&a=1&b=2', True, 'tab3', ['en', 'br'], 2], 'request': '/requests/1/3'}{'decision': ['http', 'z.test', 8080, 'GET', '/b', 'b=2&a=1&b=2', True, 'tab3', ['en', 'br'], 2], 'request': '/requests/1/3'}Passed
fixture 5{'decision': ['https', 'h.test', None, 'PUT', '/B', 'flag', True, 'tab2', [''], 1], 'request': '/requests/1/4'}{'decision': ['https', 'h.test', None, 'PUT', '/B', 'flag', False, 'tab2', [''], 1], 'request': '/requests/1/4'}Failed
fixture 6{'decision': ['https', 'h.test', None, 'GET', '/a', 'x=1', True, 'tab1', ['gzip', 'en', 'gzip'], 3], 'request': '/requests/1/5'}{'decision': ['https', 'h.test', None, 'GET', '/a', 'x=1', True, 'tab1', ['gzip', 'en', 'gzip'], 3], 'request': '/requests/1/5'}Passed

SHA-256 / 2779613a55c3fc5b125240d914c392730a6aebe1e1175df480898bea0ba7195e

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, host, port, method, path, query, partition, vary):
    return {'request': request, 'decision': [scheme, host.lower(), None if (scheme,port) in (("https",443),("http",80)) else port, method, path, query, bool(query.partition('=')[2]), partition, vary, len(vary)]} 
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', 'H.TEST', 443, 'GET', '/A', 'x=1', 'tab1', ['en', 'gzip']), {'request': '/requests/' + str(N) + '/0', 'decision': ['https', 'h.test', None, 'GET', '/A', 'x=1', True, 'tab1', ['en', 'gzip'], 2]})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'https', 'h.test', 8443, 'HEAD', '/a', 'x=2', 'tab2', ['fr', 'br']), {'request': '/requests/' + str(N) + '/1', 'decision': ['https', 'h.test', 8443, 'HEAD', '/a', 'x=2', True, 'tab2', ['fr', 'br'], 2]})
check('fixture 3', solve('/requests/' + str(N) + '/2', 'http', 'h.test', 80, 'POST', '/a', 'q=', 'tab1', []), {'request': '/requests/' + str(N) + '/2', 'decision': ['http', 'h.test', None, 'POST', '/a', 'q=', True, 'tab1', [], 0]})
check('fixture 4', solve('/requests/' + str(N) + '/3', 'http', 'Z.TEST', 8080, 'GET', '/b', 'b=2&a=1&b=2', 'tab3', ['en', 'br']), {'request': '/requests/' + str(N) + '/3', 'decision': ['http', 'z.test', 8080, 'GET', '/b', 'b=2&a=1&b=2', True, 'tab3', ['en', 'br'], 2]})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'https', 'h.test', 443, 'PUT', '/B', 'flag', 'tab2', ['']), {'request': '/requests/' + str(N) + '/4', 'decision': ['https', 'h.test', None, 'PUT', '/B', 'flag', False, 'tab2', [''], 1]})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'https', 'h.test', 443, 'GET', '/a', 'x=1', 'tab1', ['gzip', 'en', 'gzip']), {'request': '/requests/' + str(N) + '/5', 'decision': ['https', 'h.test', None, 'GET', '/a', 'x=1', True, 'tab1', ['gzip', 'en', 'gzip'], 3]})
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', 'h.test', None, 'GET', '/A', 'x=1', True, 'tab1', ['en', 'gzip'], 2], 'request': '/requests/1/0'}{'decision': ['https', 'h.test', None, 'GET', '/A', 'x=1', True, 'tab1', ['en', 'gzip'], 2], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['https', 'h.test', 8443, 'HEAD', '/a', 'x=2', True, 'tab2', ['fr', 'br'], 2], 'request': '/requests/1/1'}{'decision': ['https', 'h.test', 8443, 'HEAD', '/a', 'x=2', True, 'tab2', ['fr', 'br'], 2], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['http', 'h.test', None, 'POST', '/a', 'q=', False, 'tab1', [], 0], 'request': '/requests/1/2'}{'decision': ['http', 'h.test', None, 'POST', '/a', 'q=', True, 'tab1', [], 0], 'request': '/requests/1/2'}Failed
fixture 4{'decision': ['http', 'z.test', 8080, 'GET', '/b', 'b=2&a=1&b=2', True, 'tab3', ['en', 'br'], 2], 'request': '/requests/1/3'}{'decision': ['http', 'z.test', 8080, 'GET', '/b', 'b=2&a=1&b=2', True, 'tab3', ['en', 'br'], 2], 'request': '/requests/1/3'}Passed
fixture 5{'decision': ['https', 'h.test', None, 'PUT', '/B', 'flag', False, 'tab2', [''], 1], 'request': '/requests/1/4'}{'decision': ['https', 'h.test', None, 'PUT', '/B', 'flag', False, 'tab2', [''], 1], 'request': '/requests/1/4'}Passed
fixture 6{'decision': ['https', 'h.test', None, 'GET', '/a', 'x=1', True, 'tab1', ['gzip', 'en', 'gzip'], 3], 'request': '/requests/1/5'}{'decision': ['https', 'h.test', None, 'GET', '/a', 'x=1', True, 'tab1', ['gzip', 'en', 'gzip'], 3], 'request': '/requests/1/5'}Passed

SHA-256 / ccf25b7db797f65f188c6640a9f15367fcc326f86269621c91c4fddbceca201f

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, host, port, method, path, query, partition, vary):
    return {'request': request, 'decision': [scheme, host.lower(), None if (scheme,port) in (("https",443),("http",80)) else port, method, path, query, '=' in query, partition, vary, len(vary)]} 
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', 'H.TEST', 443, 'GET', '/A', 'x=1', 'tab1', ['en', 'gzip']), {'request': '/requests/' + str(N) + '/0', 'decision': ['https', 'h.test', None, 'GET', '/A', 'x=1', True, 'tab1', ['en', 'gzip'], 2]})
check('fixture 2', solve('/requests/' + str(N) + '/1', 'https', 'h.test', 8443, 'HEAD', '/a', 'x=2', 'tab2', ['fr', 'br']), {'request': '/requests/' + str(N) + '/1', 'decision': ['https', 'h.test', 8443, 'HEAD', '/a', 'x=2', True, 'tab2', ['fr', 'br'], 2]})
check('fixture 3', solve('/requests/' + str(N) + '/2', 'http', 'h.test', 80, 'POST', '/a', 'q=', 'tab1', []), {'request': '/requests/' + str(N) + '/2', 'decision': ['http', 'h.test', None, 'POST', '/a', 'q=', True, 'tab1', [], 0]})
check('fixture 4', solve('/requests/' + str(N) + '/3', 'http', 'Z.TEST', 8080, 'GET', '/b', 'b=2&a=1&b=2', 'tab3', ['en', 'br']), {'request': '/requests/' + str(N) + '/3', 'decision': ['http', 'z.test', 8080, 'GET', '/b', 'b=2&a=1&b=2', True, 'tab3', ['en', 'br'], 2]})
check('fixture 5', solve('/requests/' + str(N) + '/4', 'https', 'h.test', 443, 'PUT', '/B', 'flag', 'tab2', ['']), {'request': '/requests/' + str(N) + '/4', 'decision': ['https', 'h.test', None, 'PUT', '/B', 'flag', False, 'tab2', [''], 1]})
check('fixture 6', solve('/requests/' + str(N) + '/5', 'https', 'h.test', 443, 'GET', '/a', 'x=1', 'tab1', ['gzip', 'en', 'gzip']), {'request': '/requests/' + str(N) + '/5', 'decision': ['https', 'h.test', None, 'GET', '/a', 'x=1', True, 'tab1', ['gzip', 'en', 'gzip'], 3]})
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', 'h.test', None, 'GET', '/A', 'x=1', True, 'tab1', ['en', 'gzip'], 2], 'request': '/requests/1/0'}{'decision': ['https', 'h.test', None, 'GET', '/A', 'x=1', True, 'tab1', ['en', 'gzip'], 2], 'request': '/requests/1/0'}Passed
fixture 2{'decision': ['https', 'h.test', 8443, 'HEAD', '/a', 'x=2', True, 'tab2', ['fr', 'br'], 2], 'request': '/requests/1/1'}{'decision': ['https', 'h.test', 8443, 'HEAD', '/a', 'x=2', True, 'tab2', ['fr', 'br'], 2], 'request': '/requests/1/1'}Passed
fixture 3{'decision': ['http', 'h.test', None, 'POST', '/a', 'q=', True, 'tab1', [], 0], 'request': '/requests/1/2'}{'decision': ['http', 'h.test', None, 'POST', '/a', 'q=', True, 'tab1', [], 0], 'request': '/requests/1/2'}Passed
fixture 4{'decision': ['http', 'z.test', 8080, 'GET', '/b', 'b=2&a=1&b=2', True, 'tab3', ['en', 'br'], 2], 'request': '/requests/1/3'}{'decision': ['http', 'z.test', 8080, 'GET', '/b', 'b=2&a=1&b=2', True, 'tab3', ['en', 'br'], 2], 'request': '/requests/1/3'}Passed
fixture 5{'decision': ['https', 'h.test', None, 'PUT', '/B', 'flag', False, 'tab2', [''], 1], 'request': '/requests/1/4'}{'decision': ['https', 'h.test', None, 'PUT', '/B', 'flag', False, 'tab2', [''], 1], 'request': '/requests/1/4'}Passed
fixture 6{'decision': ['https', 'h.test', None, 'GET', '/a', 'x=1', True, 'tab1', ['gzip', 'en', 'gzip'], 3], 'request': '/requests/1/5'}{'decision': ['https', 'h.test', None, 'GET', '/a', 'x=1', True, 'tab1', ['gzip', 'en', 'gzip'], 3], 'request': '/requests/1/5'}Passed

SHA-256 / b89200d8af99df1cf47a4852978571c7346d8756a0c7452ea2091d61377064ac

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 2026-09-29T14:41:33.317457+00:00.

Case digest / bd2326b204118d3c2a68e78bb554b2f94388cce1dd409af56c5fc3c23a39f5b2