A nullable published_at forced the feed keyset into a non-sargable
`... OR published_at IS NULL` disjunction: with the 0067 index the planner still
applied it as a FILTER and scanned from the top of the index, so a deep `newest`
page discarded every earlier row (O(depth)).
- Migration 0068: backfill any NULLs (0 in prod) -> SET NOT NULL + DEFAULT now().
- Model: Video.published_at is now non-Optional, nullable=False, server_default now().
- feedquery: the `pub` key is nullable=False, and keyset_predicate is rebuilt
recursively so a non-nullable leading key gets a non-strict range bound
(`published_at <= v`) as an AND conjunct — an index range Cond instead of a
filter. Nullable keys keep the NULL-aware OR form (a `<= v` bound would drop
their NULL group). Equivalence proven by test_feed_keyset (all 13 sorts,
cursor-walk == unpaged).
- Ingest paths (stub_from_playlist_item, apply_video_details, playlists sync)
fall back to now() so they never write an explicit NULL.
Measured on the prod-sized localdev reseed at a ~50k-deep cursor (0067 index +
prod planner): OLD `Rows Removed by Filter: 50001`, 25,687 buffers / 9.16 ms ->
NEW `Index Cond: published_at <= v`, 1 row filtered, 47 buffers / 0.037 ms. SET
NOT NULL on 257k rows: 0.32s. Gate green (334 pytest).
Applies the three findings from the /code-review high pass on this stack:
1. to_tsquery_str moved from app.feedquery to app.utils — it's a generic
tsquery sanitizer with no feed dependency; housing it in the feed
read-model coupled the Plex browse module to the feed domain. Both feed
and plex now import it from the neutral util module.
2. feedquery.decode_cursor no longer raises fastapi.HTTPException — it raises
a plain ValueError, and routes/feed.get_feed translates it to the HTTP 400.
The read-model no longer imports fastapi, matching its "no request state"
docstring.
3. Dropped the leading underscore on the helpers that are now a cross-module
public API: feedquery {filtered_query, sort_keys, order_by, keyset_predicate,
encode_cursor, decode_cursor}; plex.query {TS_CONFIG, FIELD_COLUMNS,
field_recheck, split_csv, added_cutoff, meta_filter_conds, apply_meta_filters,
like_escape}; plex.cards {movie_card, show_card, episode_card, leaf_card}.
Genuinely-internal helpers (_channel_url, _saved_expr, _ADDED_WINDOWS,
_lib_key) keep their underscore.
Pure code motion + rename. DB-lane suite 287 passed / 2 skipped; ruff clean.
B-core-3 (2026-08-17 review): decouple two things from router modules.
1. Feed read-model → new app/feedquery.py: the pure query-building and
row-serialization layer (feed_columns, serialize, _filtered_query,
to_tsquery_str, and the keyset-pagination helpers) moves out of
routes/feed.py, which keeps only the route handlers, _feed_params, and
the request models. The three external consumers (playlists, search,
plex/browse) now import from app.feedquery instead of reaching into the
feed router.
2. admin_user sweep: 7 modules imported admin_user via app.routes.admin
(an incidental re-export of app.auth.admin_user). Repoint them all to
the definition in app.auth (audit, channels, config, quota, scheduler,
plex/admin, plex/browse); routes.admin keeps its own import for its use.
Pure code motion — no behaviour change. Full DB-lane suite 287 passed /
2 skipped; ruff clean.
peter