Move `_find_shard_with_sid`, `_resolve_shard`, `_validate_names`,
`_get_index`, and the index cache from
`decnet/web/router/transcripts/api_get_transcript.py` into
`decnet/artifacts/shards.py`. The shared module speaks
`ValueError`; the router keeps thin wrappers that translate to
`HTTPException(400)` so the route's error UX is unchanged.
This unblocks the BEHAVE-INTEGRATION Phase 4 worker wiring — the
profiler worker (and the collector's session aggregator) need to
disk-reach asciinema shards but must not import from a FastAPI
router.
11 new unit tests for the shared helper. Existing transcript router
tests pass (the shard fixture's monkeypatch points at the shared
module's ARTIFACTS_ROOT now).
The other five query endpoints (/logs, /attackers, /attacker-commands,
/bounties, /topologies/{id}) already declared le=2147483647 on offset;
these two were inconsistently uncapped. Bring them in line to close
the F4/D deep-pagination row.
Also resolves F4/T (ORM sort injection — already mitigated by the
regex pattern on /attackers sort_by, no other route accepts a column
name) and F4/D (limit cap — already universal) with code pointers.
sessrec.c emits the session_recorded SD blob with sid/service/src_ip/
duration_s/bytes/truncated — it never emitted shard_path. The web
handler still asked for fields.shard_path, got "", tripped the
sessions-YYYY-MM-DD.jsonl basename regex and returned
400 "invalid shard name" for every legitimate transcript request.
Handler now:
- Fast-paths when fields.shard_path IS present and validates
(for any future emitter or ingester that backfills it).
- Otherwise enumerates sessions-YYYY-MM-DD.jsonl shards under
ARTIFACTS_ROOT/{decky}/{service}/transcripts/ (newest first) and
returns the first one whose per-sid index contains our sid.
- Security invariant preserved: only files whose basename matches the
_SHARD_BASENAME_RE are ever opened, and they always resolve inside
ARTIFACTS_ROOT. A forged fields.shard_path is silently ignored.
- Soft-fails OSError/PermissionError on the transcripts dir (decky
containers often write it with a uid the API can't read) — returns
404 instead of a 500 traceback.
test_forged_shard_path_blocked updated to match the new semantics:
forgery is ignored, the real shard is served via fallback. The
invariant (no /etc/passwd access) is still asserted by the fact
that status is 200 with data from the test shard.
Paging, truncation surfacing, admin gate, path traversal, sid-regex and
decky-mismatch rejection for /transcripts; mirror coverage for
/attackers/{uuid}/transcripts. Flips the Session Recording box in the
roadmap (sessrec pty relay now shipping end-to-end).
Adds get_attacker_transcripts (mirror of artifacts for session_recorded
logs) and get_session_log for sid→shard resolution. New
/api/v1/transcripts/{decky}/{sid}?offset=&limit= pages asciinema events
out of the shared JSONL day-shard via an mtime-keyed byte-offset index
— never scans the whole shard per request. New
/api/v1/attackers/{uuid}/transcripts lists sessions for drilldown. Both
endpoints admin-gated.
