**Red commit:** f6290b63 — CI run will appear at
https://github.com/Kpa-clawbot/CoreScope/actionsFixes#1283.
## What
Moves all four DB write operations out of `cmd/server/` into
`cmd/ingestor/`, making the server truly read-only and eliminating the
SQLITE_BUSY VACUUM bug at its root: the server can no longer race the
ingestor for the write lock because the server has no write path.
## The four operations
| # | Was in | Now in |
|---|--------|--------|
| 1 | `cmd/server/vacuum.go` (`checkAutoVacuum`, full VACUUM +
`auto_vacuum=INCREMENTAL` migration) | `cmd/ingestor/db.go`
`Store.CheckAutoVacuum` (already existed; ingestor runs it at startup
**before** the MQTT subscriber starts → no contention) |
| 2 | `cmd/server/db.go` `PruneOldPackets` (`DELETE FROM transmissions`)
| `cmd/ingestor/maintenance.go` `Store.PruneOldPackets` (new) + 24h
ticker in `cmd/ingestor/main.go` |
| 3 | `cmd/server/db.go` `PruneOldMetrics` (`DELETE FROM
observer_metrics`) | `cmd/ingestor/db.go` `Store.PruneOldMetrics`
(already existed) |
| 4 | `cmd/server/db.go` `RemoveStaleObservers` (`UPDATE observers SET
inactive=1`) | `cmd/ingestor/db.go` `Store.RemoveStaleObservers`
(already existed) |
## HTTP surface
- **Removed:** `POST /api/admin/prune` (`handleAdminPrune`, route,
openapi entry). Operators trigger an ad-hoc prune by restarting the
ingestor.
- **Kept:** `GET /api/backup` — uses `VACUUM INTO` which writes to a
separate file, not the live DB; read-only-safe.
## Tests
- `cmd/server/readonly_invariant_test.go` (RED gate) — reflect-asserts
`PruneOldPackets`/`PruneOldMetrics`/`RemoveStaleObservers` are NOT
methods on the server's `*DB`. Fails on master, passes after this PR.
- `cmd/ingestor/issue1283_test.go` — exercises `Store.PruneOldPackets`
and the auto_vacuum=NONE → INCREMENTAL migration through
`Store.CheckAutoVacuum` with `vacuumOnStartup=true`.
## Why the bug is gone
The SQLITE_BUSY VACUUM failure happened because supervisord launched
both ingestor + server in one container; the ingestor took the write
lock for INSERTs and the server's `checkAutoVacuum` then failed to
acquire it within `busy_timeout=5000`. After this PR, only the ingestor
ever opens a writable connection, and it runs `CheckAutoVacuum`
**before** spawning the MQTT subscriber → no contention possible.
## Scope notes
- `cachedRW()` still has three pre-existing callers in `cmd/server/`
(`neighbor_persist.go`, `ensure_indexes.go`,
`from_pubkey_migration.go`). These pre-date #1283 and are not in the
issue's four-operation list. Leaving them for follow-up keeps this PR
honest about scope; AGENTS.md documents the invariant so new write paths
can't sneak in.
- PII preflight reports false positives on the Go method name
`requireAPIKey` in `routes.go` diff context — no real PII.
- Server-side neighbor-edge prune (`PruneNeighborEdges`) intentionally
left in place — out of scope of #1283.
---------
Co-authored-by: MeshCore Bot <bot@meshcore.local>
Kpa-clawbot
1da2034341