{"abstract":"A body-dropping redirect advertises the old payload length.","category":"HTTP redirects","checks":6,"contract":"Prepare a redirect replay from a bounded upload cursor. The explicit fixture inputs and outputs define a bounded offline policy; request identity must accompany the decision.","contract_signature":"request, cursor, start, length, seekable, consumed, preserved","evaluation_group":"s3-http-redirects-body-replay-cursor","failed_approach":"The partial repair uses '0' and still fails an explicit boundary or control.","family":"s3-http-redirects-body-replay-cursor-discarded-body-length","id":"FA-27956","implementations":{"attempt":{"sha256":"3637ae63d157fdd7639e0fa87e941ee2efb02324e8a843ee66c8b97c7c1ac238","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nfrom urllib.parse import urlsplit, unquote, quote\nimport posixpath\nimport re\nN = 1\nobservations = []\ndef solve(request, cursor, start, length, seekable, consumed, preserved):\n    return {'request': request, 'decision': [start if preserved else cursor, max(0, length - (cursor-start)), preserved and consumed and not seekable, 0, preserved and seekable and cursor != start]} \ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve('/requests/' + str(N) + '/0', 7, 3, 10, True, True, True), {'request': '/requests/' + str(N) + '/0', 'decision': [3, 6, False, 10, True]})\ncheck('fixture 2', solve('/requests/' + str(N) + '/1', 3, 3, 10, True, False, True), {'request': '/requests/' + str(N) + '/1', 'decision': [3, 10, False, 10, False]})\ncheck('fixture 3', solve('/requests/' + str(N) + '/2', 5, 3, 10, False, True, True), {'request': '/requests/' + str(N) + '/2', 'decision': [3, 8, True, 10, False]})\ncheck('fixture 4', solve('/requests/' + str(N) + '/3', 3, 3, 10, False, False, True), {'request': '/requests/' + str(N) + '/3', 'decision': [3, 10, False, 10, False]})\ncheck('fixture 5', solve('/requests/' + str(N) + '/4', 5, 3, 10, False, True, False), {'request': '/requests/' + str(N) + '/4', 'decision': [5, 8, False, 0, False]})\ncheck('fixture 6', solve('/requests/' + str(N) + '/5', 5, 3, 10, True, True, False), {'request': '/requests/' + str(N) + '/5', 'decision': [5, 8, False, 0, False]})\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"679b1418ed8c2d074a6b0b7eeb43e78f1cfa12b33abc6667c1db3cfebd100a41","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nfrom urllib.parse import urlsplit, unquote, quote\nimport posixpath\nimport re\nN = 1\nobservations = []\ndef solve(request, cursor, start, length, seekable, consumed, preserved):\n    return {'request': request, 'decision': [start if preserved else cursor, max(0, length - (cursor-start)), preserved and consumed and not seekable, length, preserved and seekable and cursor != start]} \ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve('/requests/' + str(N) + '/0', 7, 3, 10, True, True, True), {'request': '/requests/' + str(N) + '/0', 'decision': [3, 6, False, 10, True]})\ncheck('fixture 2', solve('/requests/' + str(N) + '/1', 3, 3, 10, True, False, True), {'request': '/requests/' + str(N) + '/1', 'decision': [3, 10, False, 10, False]})\ncheck('fixture 3', solve('/requests/' + str(N) + '/2', 5, 3, 10, False, True, True), {'request': '/requests/' + str(N) + '/2', 'decision': [3, 8, True, 10, False]})\ncheck('fixture 4', solve('/requests/' + str(N) + '/3', 3, 3, 10, False, False, True), {'request': '/requests/' + str(N) + '/3', 'decision': [3, 10, False, 10, False]})\ncheck('fixture 5', solve('/requests/' + str(N) + '/4', 5, 3, 10, False, True, False), {'request': '/requests/' + str(N) + '/4', 'decision': [5, 8, False, 0, False]})\ncheck('fixture 6', solve('/requests/' + str(N) + '/5', 5, 3, 10, True, True, False), {'request': '/requests/' + str(N) + '/5', 'decision': [5, 8, False, 0, False]})\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"s3-http-redirects-body-replay-cursor-discarded-body-length","generated_at":"2026-09-29T14:41:29.704735+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Models a redirect controller decision before following a target or exposing a redirect result.","root_cause":"The discarded-body-length decision uses 'length'; this violates the stipulated controller policy.","sha256":"01fe80ade365daf8098dc40b9a156b1673416ea5d564388e4e8c426c42c1b4e3","title":"Prepare a redirect replay from a bounded upload cursor: discarded body length · case 01","variant":1,"variant_policy":"N changes request correlation identity. Policy boundary fixtures are reused; numbered variants are not independent examples.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":37.069,"exit_code":1,"observations":[{"actual":{"decision":[3,6,false,0,true],"request":"/requests/1/0"},"check":"fixture 1","expected":{"decision":[3,6,false,10,true],"request":"/requests/1/0"},"passed":false},{"actual":{"decision":[3,10,false,0,false],"request":"/requests/1/1"},"check":"fixture 2","expected":{"decision":[3,10,false,10,false],"request":"/requests/1/1"},"passed":false},{"actual":{"decision":[3,8,true,0,false],"request":"/requests/1/2"},"check":"fixture 3","expected":{"decision":[3,8,true,10,false],"request":"/requests/1/2"},"passed":false},{"actual":{"decision":[3,10,false,0,false],"request":"/requests/1/3"},"check":"fixture 4","expected":{"decision":[3,10,false,10,false],"request":"/requests/1/3"},"passed":false},{"actual":{"decision":[5,8,false,0,false],"request":"/requests/1/4"},"check":"fixture 5","expected":{"decision":[5,8,false,0,false],"request":"/requests/1/4"},"passed":true},{"actual":{"decision":[5,8,false,0,false],"request":"/requests/1/5"},"check":"fixture 6","expected":{"decision":[5,8,false,0,false],"request":"/requests/1/5"},"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": {\"request\": \"/requests/1/0\", \"decision\": [3, 6, false, 0, true]}, \"expected\": {\"request\": \"/requests/1/0\", \"decision\": [3, 6, false, 10, true]}, \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": {\"request\": \"/requests/1/1\", \"decision\": [3, 10, false, 0, false]}, \"expected\": {\"request\": \"/requests/1/1\", \"decision\": [3, 10, false, 10, false]}, \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": {\"request\": \"/requests/1/2\", \"decision\": [3, 8, true, 0, false]}, \"expected\": {\"request\": \"/requests/1/2\", \"decision\": [3, 8, true, 10, false]}, \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": {\"request\": \"/requests/1/3\", \"decision\": [3, 10, false, 0, false]}, \"expected\": {\"request\": \"/requests/1/3\", \"decision\": [3, 10, false, 10, false]}, \"passed\": false}, {\"check\": \"fixture 5\", \"actual\": {\"request\": \"/requests/1/4\", \"decision\": [5, 8, false, 0, false]}, \"expected\": {\"request\": \"/requests/1/4\", \"decision\": [5, 8, false, 0, false]}, \"passed\": true}, {\"check\": \"fixture 6\", \"actual\": {\"request\": \"/requests/1/5\", \"decision\": [5, 8, false, 0, false]}, \"expected\": {\"request\": \"/requests/1/5\", \"decision\": [5, 8, false, 0, false]}, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.356,"exit_code":1,"observations":[{"actual":{"decision":[3,6,false,10,true],"request":"/requests/1/0"},"check":"fixture 1","expected":{"decision":[3,6,false,10,true],"request":"/requests/1/0"},"passed":true},{"actual":{"decision":[3,10,false,10,false],"request":"/requests/1/1"},"check":"fixture 2","expected":{"decision":[3,10,false,10,false],"request":"/requests/1/1"},"passed":true},{"actual":{"decision":[3,8,true,10,false],"request":"/requests/1/2"},"check":"fixture 3","expected":{"decision":[3,8,true,10,false],"request":"/requests/1/2"},"passed":true},{"actual":{"decision":[3,10,false,10,false],"request":"/requests/1/3"},"check":"fixture 4","expected":{"decision":[3,10,false,10,false],"request":"/requests/1/3"},"passed":true},{"actual":{"decision":[5,8,false,10,false],"request":"/requests/1/4"},"check":"fixture 5","expected":{"decision":[5,8,false,0,false],"request":"/requests/1/4"},"passed":false},{"actual":{"decision":[5,8,false,10,false],"request":"/requests/1/5"},"check":"fixture 6","expected":{"decision":[5,8,false,0,false],"request":"/requests/1/5"},"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": {\"request\": \"/requests/1/0\", \"decision\": [3, 6, false, 10, true]}, \"expected\": {\"request\": \"/requests/1/0\", \"decision\": [3, 6, false, 10, true]}, \"passed\": true}, {\"check\": \"fixture 2\", \"actual\": {\"request\": \"/requests/1/1\", \"decision\": [3, 10, false, 10, false]}, \"expected\": {\"request\": \"/requests/1/1\", \"decision\": [3, 10, false, 10, false]}, \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": {\"request\": \"/requests/1/2\", \"decision\": [3, 8, true, 10, false]}, \"expected\": {\"request\": \"/requests/1/2\", \"decision\": [3, 8, true, 10, false]}, \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": {\"request\": \"/requests/1/3\", \"decision\": [3, 10, false, 10, false]}, \"expected\": {\"request\": \"/requests/1/3\", \"decision\": [3, 10, false, 10, false]}, \"passed\": true}, {\"check\": \"fixture 5\", \"actual\": {\"request\": \"/requests/1/4\", \"decision\": [5, 8, false, 10, false]}, \"expected\": {\"request\": \"/requests/1/4\", \"decision\": [5, 8, false, 0, false]}, \"passed\": false}, {\"check\": \"fixture 6\", \"actual\": {\"request\": \"/requests/1/5\", \"decision\": [5, 8, false, 10, false]}, \"expected\": {\"request\": \"/requests/1/5\", \"decision\": [5, 8, false, 0, false]}, \"passed\": false}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}