The code cited its plan instead of saying why: `E28 review J4`, `(R6 S3b)`, `S1 justified…`,
`deep-review round 5`. That plan lives in the private ops repo, so for every reader of this one the
citation was noise, and a sentence whose subject was the plan step ("round 2 showed…") hid its
lesson behind an id. Each one is gone and the "why" kept: a bare citation is deleted, a sentence
carrying a lesson is reworded around it ("a later attempt showed…").
Measured (`scripts/audit_metrics.py`, product code): 652 lines in 270 files carried an epic code by
the definition the next commit holds (507 / 241 by the old, two-digit-only one) -> 0. Across all
code, tests, scripts and configs: ~1100 epic-code lines plus ~320 sprint/round ids.
Behaviour unchanged, checked mechanically: every changed .py file has the same AST once docstrings
are blanked; css/sh/toml/yml/json files are identical once comments are stripped; the only
non-comment changes in TS/JS are test titles, one description string in a contract table, and five
ESLint messages, whose text is all the gates snapshot diff holds. Not touched: Markdown (docs and
the changelog keep their history), Alembic migrations, TV episode notation (`S2 · E5`), DESIGN.md
ids (`C1`, `B4`, `S3h`), tracker ids (`SEC-16`, `DX-17`).
One stale claim fixed on the way: test_hls_reaper's docstring said the player checkpoints "every
10 s whether or not it is playing", which plex/stream.py calls wrong; it now says what the code does.
Deep-review round 1 found the new tests asserted end-state only, so both
safety mechanisms this change adds were untested (a regression would ship
green):
- Per-page cursor durability: add test_a_mid_run_failure_leaves_the_prior_page
_durably_committed, which fails the 2nd page's fetch after page 1 committed
and asserts the cursor + rows are already persisted (re-read via db.expire).
Mutation-verified: reverting to a single end-of-loop commit makes it fail
while the pre-existing paging tests stay green — the property the original
test could not distinguish.
- Reserve guard: add test_backfill_reserve_reached_tracks_the_boundary, driving
real record_usage spend across the 9000/2000 default boundary and asserting
the un-mocked quota.backfill_reserve_reached() flips at exactly remaining<=reserve.
Full backend suite: 244 passed, 2 skipped (network-gated).
Transaction ownership (C-A5):
- quota.record_usage / log_action write in their OWN SessionLocal(), committed
immediately, and no longer take/commit the caller's db. The spend stays DURABLE
regardless of the caller (read-only YouTube paths never commit; a failed job rolls
back) — under-counting the shared daily budget would risk overspending the real
YouTube quota — AND quota stops flushing a job's partial state mid-run behind its
own `except: db.rollback()`. units_used_today switches to a scalar SELECT so
measured()'s before/after diff sees the separate session's commits (READ COMMITTED).
Call sites updated (youtube/client.py ×3, routes/search.py ×1).
- plex sync commits PER SECTION (moved the end-of-loop commit inside), so a PlexError
on a later library keeps the ones already mirrored (idempotent; next run reconciles).
The sync jobs did NOT rely on record_usage's incidental commit for persistence — their
per-item functions (apply_rss_feed, backfill_channel_recent, import_subscriptions,
sync_user_playlists, apply_channel_autotags) all commit internally, so the in-loop
rollback handlers already isolate a failed item. No loop restructuring needed.
DB-lane tests (test_quota_ownership, 4): spend survives a caller rollback while the
caller's uncommitted row does NOT leak; accumulation; measured-style mid-txn read.
Gate: ruff clean; DB lane 180 green.
peter