FA-26696 / HTTP ranges / Open access

Unsatisfied range metadata reports the complete length without invented endpoints · case 01

Unsatisfied range metadata reports the complete length without invented endpoints.

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

ROOT CAUSE

The content-range-unsatisfied-format decision uses return f"bytes 0-{length-1}/{length}".

VERIFIED REPAIR

Apply the bounded decision exactly: return f"bytes */{length}"

Unsuccessful approach: The partial repair uses return f"bytes */{length}" if length else "bytes */*", which still violates the stated contract.

Case contract

For known nonnegative complete length return bytes */length, including empty representations.

Why this case matters

Range responses combine representation identity, conditional requests, framing, and partial-object state.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(length):
    return f"bytes 0-{length-1}/{length}"
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('content-range-unsatisfied-format fixture 0', solve(N), "bytes */"+str(N))
check('content-range-unsatisfied-format fixture 1', solve(0), "bytes */0")
check('content-range-unsatisfied-format fixture 2', solve(2*N), "bytes */"+str(2*N))
check('content-range-unsatisfied-format fixture 3', solve(1), "bytes */1")
check('content-range-unsatisfied-format fixture 4', solve(10), "bytes */10")
check('content-range-unsatisfied-format fixture 5', solve(100+N), "bytes */"+str(100+N))
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 fixture	Actual	Expected	Outcome
content-range-unsatisfied-format fixture 0	`bytes 0-0/1`	`bytes */1`	Failed
content-range-unsatisfied-format fixture 1	`bytes 0--1/0`	`bytes */0`	Failed
content-range-unsatisfied-format fixture 2	`bytes 0-1/2`	`bytes */2`	Failed
content-range-unsatisfied-format fixture 3	`bytes 0-0/1`	`bytes */1`	Failed
content-range-unsatisfied-format fixture 4	`bytes 0-9/10`	`bytes */10`	Failed
content-range-unsatisfied-format fixture 5	`bytes 0-100/101`	`bytes */101`	Failed

SHA-256 / 2af1e6a540ddee8b0ea66fe20bd0774dfbf2b172c332c40b7cfe02b75b5512d3

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(length):
    return f"bytes */{length}" if length else "bytes */*"
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('content-range-unsatisfied-format fixture 0', solve(N), "bytes */"+str(N))
check('content-range-unsatisfied-format fixture 1', solve(0), "bytes */0")
check('content-range-unsatisfied-format fixture 2', solve(2*N), "bytes */"+str(2*N))
check('content-range-unsatisfied-format fixture 3', solve(1), "bytes */1")
check('content-range-unsatisfied-format fixture 4', solve(10), "bytes */10")
check('content-range-unsatisfied-format fixture 5', solve(100+N), "bytes */"+str(100+N))
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 fixture	Actual	Expected	Outcome
content-range-unsatisfied-format fixture 0	`bytes */1`	`bytes */1`	Passed
content-range-unsatisfied-format fixture 1	`bytes /`	`bytes */0`	Failed
content-range-unsatisfied-format fixture 2	`bytes */2`	`bytes */2`	Passed
content-range-unsatisfied-format fixture 3	`bytes */1`	`bytes */1`	Passed
content-range-unsatisfied-format fixture 4	`bytes */10`	`bytes */10`	Passed
content-range-unsatisfied-format fixture 5	`bytes */101`	`bytes */101`	Passed

SHA-256 / c57bc500357cb042472715763ac139a1b39e77b05513962973b3e6051ff81cfe

3 / The verified repair

Exit 0

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(length):
    return f"bytes */{length}"
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('content-range-unsatisfied-format fixture 0', solve(N), "bytes */"+str(N))
check('content-range-unsatisfied-format fixture 1', solve(0), "bytes */0")
check('content-range-unsatisfied-format fixture 2', solve(2*N), "bytes */"+str(2*N))
check('content-range-unsatisfied-format fixture 3', solve(1), "bytes */1")
check('content-range-unsatisfied-format fixture 4', solve(10), "bytes */10")
check('content-range-unsatisfied-format fixture 5', solve(100+N), "bytes */"+str(100+N))
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 fixture	Actual	Expected	Outcome
content-range-unsatisfied-format fixture 0	`bytes */1`	`bytes */1`	Passed
content-range-unsatisfied-format fixture 1	`bytes */0`	`bytes */0`	Passed
content-range-unsatisfied-format fixture 2	`bytes */2`	`bytes */2`	Passed
content-range-unsatisfied-format fixture 3	`bytes */1`	`bytes */1`	Passed
content-range-unsatisfied-format fixture 4	`bytes */10`	`bytes */10`	Passed
content-range-unsatisfied-format fixture 5	`bytes */101`	`bytes */101`	Passed

SHA-256 / 2ec8e1a858f264ba5b37afbc147e792d0830ae96f00e8a862680e682dad11991

Verification & scope

Deterministic simplified range service, with stipulated local policies and already parsed trusted inputs; not a complete HTTP implementation. 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 2026-09-29T14:41:18.259825+00:00.

Case digest / 412b8b1bb29d4d81cae1f3981294526044ba190d25a1dbaf8673038c25a5fc8e