feat(server): drain resident WAL writers on graceful shutdown - #167
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`ShardWriter` has no `Drop`, so its background tasks are only reclaimed by an explicit `close().await`. At process shutdown the runtime is about to stop, so the detached best-effort close in `RolloutStore::Drop` may never run. Add `AppState::shutdown()` to await `close()` on every resident rollout writer, and call it in `main` after `axum::serve` returns (connections drained). Idempotent and a no-op on an empty cache. Co-Authored-By: Claude Opus 4 <noreply@anthropic.com>
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…#168) ## Summary - `AppError::from_lance` took `impl Display` and string-matched the rendered message (`"not found"`, `"Invalid"`, `"DatasetNotFound"`). That is brittle (breaks on any Display wording change) and over-broad (any message containing `"Invalid"` — e.g. `InvalidTableLocation`, `InvalidRef` — became a 400). - Now takes `lance::Error` by value (re-exported as `LanceError` from `lance-context-core`) and matches **typed variants**: `DatasetNotFound`/`NotFound` → 404, `DatasetAlreadyExists` → 409, `InvalidInput`/`SchemaMismatch` → 400, else 500. - The one signal Lance exposes no dedicated variant for — "compaction already in progress", raised as an `ArrowError::InvalidArgumentError` folded into Lance's generic `Arrow` variant — is still matched by text, but checked **up front** so it keeps mapping to 409 `COMPACTION_IN_PROGRESS`. - All call sites already passed `lance::Error`, so no caller changes were needed. ## Test plan - [x] `cargo test -p lance-context-server error::` (typed-variant mapping + Arrow-wrapped compaction case) - [x] `cargo clippy -p lance-context-server -p lance-context-core` clean - [x] `cargo fmt --all` Independent of #166 and #167. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-authored-by: Claude Opus 4 <noreply@anthropic.com>
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Summary
ShardWriterhas noDrop, so its background tasks are only reclaimed by an explicitclose().await. At process shutdown the runtime is about to stop, so the detached best-effort close inRolloutStore::Dropmay never run — leaking those tasks / skipping a clean drain.AppState::shutdown(), which snapshots the resident LRU and awaitsRolloutStore::close()on each handle. Wired intomainright afteraxum::serve(...).with_graceful_shutdown(...)returns (connections already drained). Idempotent and a no-op on an empty cache.Test plan
cargo test -p lance-context-server state::(incl. newshutdown_closes_resident_writers)cargo clippy -p lance-context-servercleancargo fmt --allNote: this branch is independent of #166; it does not touch the
cleanup_interval_secsremoval.🤖 Generated with Claude Code