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FA-28591 / HTTP redirects / Open access

Translate a redirect between internal and public application mounts: mount boundary · case 01

Translate a redirect between internal and public application mounts: the mount boundary branch emits an incorrect decision.

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

ROOT CAUSE

The mount-boundary decision uses 'path.startswith(internal)'; this violates the stipulated controller policy.

VERIFIED REPAIR

At this decision use "path == internal or path.startswith(internal.rstrip('/')+'/')", preserving the other controller outputs.

Unsuccessful approach: The partial repair uses 'path == internal' and still fails an explicit boundary or control.

Case contract

Translate a redirect between internal and public application mounts. 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, path, internal, external, query, trailing, absolute):
    return {'request': request, 'decision': [path.startswith(internal), path[len(internal):] if path == internal or path.startswith(internal.rstrip('/')+'/') else path, external or '/', ('?' + query) if query else '', path+'/' if trailing and not path.endswith('/') else path, 'absolute' if absolute else 'relative', path[1:] if internal == '/' else path, external.rstrip('/') + '/' + path.lstrip('/'), ('/' + external.lstrip('/')) if external else '/', path.startswith(internal.rstrip('/')+'/') or path == internal]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', '/app/a', '/app', '/public', 'x=1', False, False), {'request': '/requests/' + str(N) + '/0', 'decision': [True, '/a', '/public', '?x=1', '/app/a', 'relative', '/app/a', '/public/app/a', '/public', True]})
check('fixture 2', solve('/requests/' + str(N) + '/1', '/apple/a', '/app', '/public', '', False, False), {'request': '/requests/' + str(N) + '/1', 'decision': [False, '/apple/a', '/public', '', '/apple/a', 'relative', '/apple/a', '/public/apple/a', '/public', False]})
check('fixture 3', solve('/requests/' + str(N) + '/2', '/app', '/app', '/public', 'q=', True, False), {'request': '/requests/' + str(N) + '/2', 'decision': [True, '', '/public', '?q=', '/app/', 'relative', '/app', '/public/app', '/public', True]})
check('fixture 4', solve('/requests/' + str(N) + '/3', '/app/a/app', '/app', '/v2', 'k=1&k=2', True, True), {'request': '/requests/' + str(N) + '/3', 'decision': [True, '/a/app', '/v2', '?k=1&k=2', '/app/a/app/', 'absolute', '/app/a/app', '/v2/app/a/app', '/v2', True]})
check('fixture 5', solve('/requests/' + str(N) + '/4', '/', '/', '/edge', '', False, True), {'request': '/requests/' + str(N) + '/4', 'decision': [True, '', '/edge', '', '/', 'absolute', '', '/edge/', '/edge', True]})
check('fixture 6', solve('/requests/' + str(N) + '/5', '/app/a', '/app', '', 'x=2', False, True), {'request': '/requests/' + str(N) + '/5', 'decision': [True, '/a', '/', '?x=2', '/app/a', 'absolute', '/app/a', '/app/a', '/', True]})
check('fixture 7', solve('/requests/' + str(N) + '/6', '/app/a/', '/app', '/public/', '', True, False), {'request': '/requests/' + str(N) + '/6', 'decision': [True, '/a/', '/public/', '', '/app/a/', 'relative', '/app/a/', '/public/app/a/', '/public/', 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': [True, '/a', '/public', '?x=1', '/app/a', 'relative', '/app/a', '/public/app/a', '/public', True], 'request': '/requests/1/0'}{'decision': [True, '/a', '/public', '?x=1', '/app/a', 'relative', '/app/a', '/public/app/a', '/public', True], 'request': '/requests/1/0'}Passed
fixture 2{'decision': [True, '/apple/a', '/public', '', '/apple/a', 'relative', '/apple/a', '/public/apple/a', '/public', False], 'request': '/requests/1/1'}{'decision': [False, '/apple/a', '/public', '', '/apple/a', 'relative', '/apple/a', '/public/apple/a', '/public', False], 'request': '/requests/1/1'}Failed
fixture 3{'decision': [True, '', '/public', '?q=', '/app/', 'relative', '/app', '/public/app', '/public', True], 'request': '/requests/1/2'}{'decision': [True, '', '/public', '?q=', '/app/', 'relative', '/app', '/public/app', '/public', True], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [True, '/a/app', '/v2', '?k=1&k=2', '/app/a/app/', 'absolute', '/app/a/app', '/v2/app/a/app', '/v2', True], 'request': '/requests/1/3'}{'decision': [True, '/a/app', '/v2', '?k=1&k=2', '/app/a/app/', 'absolute', '/app/a/app', '/v2/app/a/app', '/v2', True], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [True, '', '/edge', '', '/', 'absolute', '', '/edge/', '/edge', True], 'request': '/requests/1/4'}{'decision': [True, '', '/edge', '', '/', 'absolute', '', '/edge/', '/edge', True], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [True, '/a', '/', '?x=2', '/app/a', 'absolute', '/app/a', '/app/a', '/', True], 'request': '/requests/1/5'}{'decision': [True, '/a', '/', '?x=2', '/app/a', 'absolute', '/app/a', '/app/a', '/', True], 'request': '/requests/1/5'}Passed
fixture 7{'decision': [True, '/a/', '/public/', '', '/app/a/', 'relative', '/app/a/', '/public/app/a/', '/public/', True], 'request': '/requests/1/6'}{'decision': [True, '/a/', '/public/', '', '/app/a/', 'relative', '/app/a/', '/public/app/a/', '/public/', True], 'request': '/requests/1/6'}Passed

SHA-256 / f86532b36c412caa202236f925e442b179341b3c1383b4e8a59a8f711054f7ea

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, path, internal, external, query, trailing, absolute):
    return {'request': request, 'decision': [path == internal, path[len(internal):] if path == internal or path.startswith(internal.rstrip('/')+'/') else path, external or '/', ('?' + query) if query else '', path+'/' if trailing and not path.endswith('/') else path, 'absolute' if absolute else 'relative', path[1:] if internal == '/' else path, external.rstrip('/') + '/' + path.lstrip('/'), ('/' + external.lstrip('/')) if external else '/', path.startswith(internal.rstrip('/')+'/') or path == internal]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', '/app/a', '/app', '/public', 'x=1', False, False), {'request': '/requests/' + str(N) + '/0', 'decision': [True, '/a', '/public', '?x=1', '/app/a', 'relative', '/app/a', '/public/app/a', '/public', True]})
check('fixture 2', solve('/requests/' + str(N) + '/1', '/apple/a', '/app', '/public', '', False, False), {'request': '/requests/' + str(N) + '/1', 'decision': [False, '/apple/a', '/public', '', '/apple/a', 'relative', '/apple/a', '/public/apple/a', '/public', False]})
check('fixture 3', solve('/requests/' + str(N) + '/2', '/app', '/app', '/public', 'q=', True, False), {'request': '/requests/' + str(N) + '/2', 'decision': [True, '', '/public', '?q=', '/app/', 'relative', '/app', '/public/app', '/public', True]})
check('fixture 4', solve('/requests/' + str(N) + '/3', '/app/a/app', '/app', '/v2', 'k=1&k=2', True, True), {'request': '/requests/' + str(N) + '/3', 'decision': [True, '/a/app', '/v2', '?k=1&k=2', '/app/a/app/', 'absolute', '/app/a/app', '/v2/app/a/app', '/v2', True]})
check('fixture 5', solve('/requests/' + str(N) + '/4', '/', '/', '/edge', '', False, True), {'request': '/requests/' + str(N) + '/4', 'decision': [True, '', '/edge', '', '/', 'absolute', '', '/edge/', '/edge', True]})
check('fixture 6', solve('/requests/' + str(N) + '/5', '/app/a', '/app', '', 'x=2', False, True), {'request': '/requests/' + str(N) + '/5', 'decision': [True, '/a', '/', '?x=2', '/app/a', 'absolute', '/app/a', '/app/a', '/', True]})
check('fixture 7', solve('/requests/' + str(N) + '/6', '/app/a/', '/app', '/public/', '', True, False), {'request': '/requests/' + str(N) + '/6', 'decision': [True, '/a/', '/public/', '', '/app/a/', 'relative', '/app/a/', '/public/app/a/', '/public/', 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': [False, '/a', '/public', '?x=1', '/app/a', 'relative', '/app/a', '/public/app/a', '/public', True], 'request': '/requests/1/0'}{'decision': [True, '/a', '/public', '?x=1', '/app/a', 'relative', '/app/a', '/public/app/a', '/public', True], 'request': '/requests/1/0'}Failed
fixture 2{'decision': [False, '/apple/a', '/public', '', '/apple/a', 'relative', '/apple/a', '/public/apple/a', '/public', False], 'request': '/requests/1/1'}{'decision': [False, '/apple/a', '/public', '', '/apple/a', 'relative', '/apple/a', '/public/apple/a', '/public', False], 'request': '/requests/1/1'}Passed
fixture 3{'decision': [True, '', '/public', '?q=', '/app/', 'relative', '/app', '/public/app', '/public', True], 'request': '/requests/1/2'}{'decision': [True, '', '/public', '?q=', '/app/', 'relative', '/app', '/public/app', '/public', True], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [False, '/a/app', '/v2', '?k=1&k=2', '/app/a/app/', 'absolute', '/app/a/app', '/v2/app/a/app', '/v2', True], 'request': '/requests/1/3'}{'decision': [True, '/a/app', '/v2', '?k=1&k=2', '/app/a/app/', 'absolute', '/app/a/app', '/v2/app/a/app', '/v2', True], 'request': '/requests/1/3'}Failed
fixture 5{'decision': [True, '', '/edge', '', '/', 'absolute', '', '/edge/', '/edge', True], 'request': '/requests/1/4'}{'decision': [True, '', '/edge', '', '/', 'absolute', '', '/edge/', '/edge', True], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [False, '/a', '/', '?x=2', '/app/a', 'absolute', '/app/a', '/app/a', '/', True], 'request': '/requests/1/5'}{'decision': [True, '/a', '/', '?x=2', '/app/a', 'absolute', '/app/a', '/app/a', '/', True], 'request': '/requests/1/5'}Failed
fixture 7{'decision': [False, '/a/', '/public/', '', '/app/a/', 'relative', '/app/a/', '/public/app/a/', '/public/', True], 'request': '/requests/1/6'}{'decision': [True, '/a/', '/public/', '', '/app/a/', 'relative', '/app/a/', '/public/app/a/', '/public/', True], 'request': '/requests/1/6'}Failed

SHA-256 / 301865f6f0ded3c3fd82bd302c638cd7f4face0f198e61d7460e77355113960e

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, path, internal, external, query, trailing, absolute):
    return {'request': request, 'decision': [path == internal or path.startswith(internal.rstrip('/')+'/'), path[len(internal):] if path == internal or path.startswith(internal.rstrip('/')+'/') else path, external or '/', ('?' + query) if query else '', path+'/' if trailing and not path.endswith('/') else path, 'absolute' if absolute else 'relative', path[1:] if internal == '/' else path, external.rstrip('/') + '/' + path.lstrip('/'), ('/' + external.lstrip('/')) if external else '/', path.startswith(internal.rstrip('/')+'/') or path == internal]} 
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve('/requests/' + str(N) + '/0', '/app/a', '/app', '/public', 'x=1', False, False), {'request': '/requests/' + str(N) + '/0', 'decision': [True, '/a', '/public', '?x=1', '/app/a', 'relative', '/app/a', '/public/app/a', '/public', True]})
check('fixture 2', solve('/requests/' + str(N) + '/1', '/apple/a', '/app', '/public', '', False, False), {'request': '/requests/' + str(N) + '/1', 'decision': [False, '/apple/a', '/public', '', '/apple/a', 'relative', '/apple/a', '/public/apple/a', '/public', False]})
check('fixture 3', solve('/requests/' + str(N) + '/2', '/app', '/app', '/public', 'q=', True, False), {'request': '/requests/' + str(N) + '/2', 'decision': [True, '', '/public', '?q=', '/app/', 'relative', '/app', '/public/app', '/public', True]})
check('fixture 4', solve('/requests/' + str(N) + '/3', '/app/a/app', '/app', '/v2', 'k=1&k=2', True, True), {'request': '/requests/' + str(N) + '/3', 'decision': [True, '/a/app', '/v2', '?k=1&k=2', '/app/a/app/', 'absolute', '/app/a/app', '/v2/app/a/app', '/v2', True]})
check('fixture 5', solve('/requests/' + str(N) + '/4', '/', '/', '/edge', '', False, True), {'request': '/requests/' + str(N) + '/4', 'decision': [True, '', '/edge', '', '/', 'absolute', '', '/edge/', '/edge', True]})
check('fixture 6', solve('/requests/' + str(N) + '/5', '/app/a', '/app', '', 'x=2', False, True), {'request': '/requests/' + str(N) + '/5', 'decision': [True, '/a', '/', '?x=2', '/app/a', 'absolute', '/app/a', '/app/a', '/', True]})
check('fixture 7', solve('/requests/' + str(N) + '/6', '/app/a/', '/app', '/public/', '', True, False), {'request': '/requests/' + str(N) + '/6', 'decision': [True, '/a/', '/public/', '', '/app/a/', 'relative', '/app/a/', '/public/app/a/', '/public/', 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': [True, '/a', '/public', '?x=1', '/app/a', 'relative', '/app/a', '/public/app/a', '/public', True], 'request': '/requests/1/0'}{'decision': [True, '/a', '/public', '?x=1', '/app/a', 'relative', '/app/a', '/public/app/a', '/public', True], 'request': '/requests/1/0'}Passed
fixture 2{'decision': [False, '/apple/a', '/public', '', '/apple/a', 'relative', '/apple/a', '/public/apple/a', '/public', False], 'request': '/requests/1/1'}{'decision': [False, '/apple/a', '/public', '', '/apple/a', 'relative', '/apple/a', '/public/apple/a', '/public', False], 'request': '/requests/1/1'}Passed
fixture 3{'decision': [True, '', '/public', '?q=', '/app/', 'relative', '/app', '/public/app', '/public', True], 'request': '/requests/1/2'}{'decision': [True, '', '/public', '?q=', '/app/', 'relative', '/app', '/public/app', '/public', True], 'request': '/requests/1/2'}Passed
fixture 4{'decision': [True, '/a/app', '/v2', '?k=1&k=2', '/app/a/app/', 'absolute', '/app/a/app', '/v2/app/a/app', '/v2', True], 'request': '/requests/1/3'}{'decision': [True, '/a/app', '/v2', '?k=1&k=2', '/app/a/app/', 'absolute', '/app/a/app', '/v2/app/a/app', '/v2', True], 'request': '/requests/1/3'}Passed
fixture 5{'decision': [True, '', '/edge', '', '/', 'absolute', '', '/edge/', '/edge', True], 'request': '/requests/1/4'}{'decision': [True, '', '/edge', '', '/', 'absolute', '', '/edge/', '/edge', True], 'request': '/requests/1/4'}Passed
fixture 6{'decision': [True, '/a', '/', '?x=2', '/app/a', 'absolute', '/app/a', '/app/a', '/', True], 'request': '/requests/1/5'}{'decision': [True, '/a', '/', '?x=2', '/app/a', 'absolute', '/app/a', '/app/a', '/', True], 'request': '/requests/1/5'}Passed
fixture 7{'decision': [True, '/a/', '/public/', '', '/app/a/', 'relative', '/app/a/', '/public/app/a/', '/public/', True], 'request': '/requests/1/6'}{'decision': [True, '/a/', '/public/', '', '/app/a/', 'relative', '/app/a/', '/public/app/a/', '/public/', True], 'request': '/requests/1/6'}Passed

SHA-256 / df8325e429fac4dabdd3165559af920b21c496e4205e422e7081901d80104ecd

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 2026-09-29T14:41:35.256890+00:00.

Case digest / 8b4023b33cfd483fdb982c059d96dfa258de7c06be38c829f2df6e41ac6f309b