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FA-6771 / HTTP caching / Open access

Cache key retains query but discards fragment · case 01

Cache key retains query but discards fragment.

Verified by executionVariant 1 · 4 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The faulty implementation uses `url` for the cache-key-retains-query-but-discards-fragment decision.

VERIFIED REPAIR

Apply the explicit cache-key-retains-query-but-discards-fragment contract, including the tested boundary and negative cases.

Unsuccessful approach: The attempted repair uses `url.split('?',1)[0].split('#',1)[0]` and still violates a separate fixture.

Case contract

Bounded offline decision model: cache key retains query but discards fragment. Inputs are already validated protocol fields; the explicit fixtures define the supported policy, not a complete protocol implementation.

Why this case matters

This deterministic http caching model isolates the cache-key-retains-query-but-discards-fragment policy at a network component boundary.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(url):
    return url
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve('/a?q=1#x'), '/a?q=1')", "check('fixture 2', solve('/a?q=2'), '/a?q=2')", "check('fixture 3', solve('/a#x'), '/a')", "check('fixture 4', solve('/a'), '/a')"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
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 2/a?q=2/a?q=2Passed
fixture 3/a#x/aFailed
fixture 4/a/aPassed
fixture 1/a?q=1#x/a?q=1Failed

SHA-256 / b25b8e8ab96a651a8efbf461104bf649c6e5d7db1adbe06c623c77602a5239ba

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(url):
    return url.split('?',1)[0].split('#',1)[0]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve('/a?q=1#x'), '/a?q=1')", "check('fixture 2', solve('/a?q=2'), '/a?q=2')", "check('fixture 3', solve('/a#x'), '/a')", "check('fixture 4', solve('/a'), '/a')"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
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 2/a/a?q=2Failed
fixture 3/a/aPassed
fixture 4/a/aPassed
fixture 1/a/a?q=1Failed

SHA-256 / 617e6f241b8d78862dfd86ab73f443001cc50429ea2023fabcdd56996f0a2e01

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(url):
    return url.split('#',1)[0]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve('/a?q=1#x'), '/a?q=1')", "check('fixture 2', solve('/a?q=2'), '/a?q=2')", "check('fixture 3', solve('/a#x'), '/a')", "check('fixture 4', solve('/a'), '/a')"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
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 2/a?q=2/a?q=2Passed
fixture 3/a/aPassed
fixture 4/a/aPassed
fixture 1/a?q=1/a?q=1Passed

SHA-256 / 5b16e96276436e6b3d9bf61118bce43cfce507f13fde83dc1786be1ebdf38eeb

Verification & scope

Bounded deterministic policy model over validated inputs; not a complete protocol stack or an interoperability claim. The five variants rotate the same explicit fixture set. 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 2026-09-29T14:38:04.984318+00:00.

Case digest / 931d8cea219148b37654ee72f0116e1126c7e66dc745ef69f3ae8e36a25fd0ad