Previous attempt (shield + sync invalidate fallback) didn't work
because shield only protects against cancellation from *other* tasks.
When the caller task itself is cancelled mid-query, its next await
re-raises CancelledError as soon as the shielded coroutine yields —
rollback inside session.close() never completes, the aiomysql
connection is orphaned, and the pool logs 'non-checked-in connection'
when GC finally reaches it.
Hand exception-path cleanup to loop.create_task() so the new task
isn't subject to the caller's pending cancellation. close() (and the
invalidate() fallback for a dead connection) runs to completion.
Success path is unchanged — still awaits close() inline so callers
see commit visibility and pool release before proceeding.
Under high-concurrency MySQL load, uvicorn cancels request tasks when
clients disconnect. If cancellation lands mid-query, session.close()
tries to ROLLBACK on a connection that aiomysql has already marked as
closed — raising InterfaceError("Cancelled during execution") and
leaving the connection checked-out until GC, which the pool then
warns about as a 'non-checked-in connection'.
The old fallback tried sync.rollback() + sync.close(), but those still
go through the async driver and fail the same way on a dead connection.
Replace them with session.sync_session.invalidate(), which just flips
the pool's internal record — no I/O, so it can't be cancelled — and
tells the pool to drop the connection immediately instead of waiting
for garbage collection.
Adds BaseRepository.add_logs (default: loops add_log for backwards
compatibility) and a real single-session/single-commit implementation
on SQLModelRepository. Introduces DECNET_BATCH_SIZE (default 100) and
DECNET_BATCH_MAX_WAIT_MS (default 250) so the ingester can flush on
either a size or a time bound when it adopts the new method.
Ingester wiring is deferred to a later pass — the single-log path was
deadlocking tests when flushed during lifespan teardown, so this change
ships the DB primitive alone.
stdlib json was FastAPI's default. Every response body, every SSE frame,
and every add_log/state/payload write paid the stdlib encode cost.
- pyproject.toml: add orjson>=3.10 as a core dep.
- decnet/web/api.py: default_response_class=ORJSONResponse on the
FastAPI app, so every endpoint return goes through orjson without
touching call sites. Explicit JSONResponse sites in the validation
exception handlers migrated to ORJSONResponse for consistency.
- health endpoint's explicit JSONResponse → ORJSONResponse.
- SSE stream (api_stream_events.py): 6 json.dumps call sites →
orjson.dumps(...).decode() — the per-event frames that fire on every
sse tick.
- sqlmodel_repo.py: encode sites on the log-insert path switched to
orjson (fields, payload, state value). Parser sites (json.loads)
left as-is for now — not on the measured hot path.
_ensure_admin_user was strict insert-if-missing: once a stale hash landed
in decnet.db (e.g. from a deploy that used a different DECNET_ADMIN_PASSWORD),
login silently 401'd because changing the env var later had no effect.
Now on startup: if the admin still has must_change_password=True (they
never finalized their own password), re-sync the hash from the current
env var. Once the admin sets a real password, we leave it alone.
Found via locustfile.py login storm — see tests/test_admin_seed.py.
Note: this commit also bundles uncommitted pool-management work already
present in sqlmodel_repo.py from prior sessions.
Cold start fetched all logs in one bulk query then processed them in a tight
synchronous loop with no yields, blocking the asyncio event loop for seconds
on datasets of 30K+ rows. This stalled every concurrent await — including the
SSE stream generator's initial DB calls — causing the dashboard to show
INITIALIZING SENSORS indefinitely.
Changes:
- Drop _cold_start() and get_all_logs_raw(); uninitialized state now runs the
same cursor loop as incremental, starting from last_log_id=0
- Yield to the event loop after every _BATCH_SIZE rows (asyncio.sleep(0))
- Add SSE keepalive comment as first yield so the connection flushes before
any DB work begins
- Add Cache-Control/X-Accel-Buffering headers to StreamingResponse
- Implement MySQLRepository extending BaseRepository
- Add SQLAlchemy/SQLModel ORM abstraction layer (sqlmodel_repo.py)
- Support connection pooling and tuning via DECNET_DB_URL env var
- Cross-compatible with SQLite backend via factory pattern
- Prepared for production deployment with MySQL SIEM/ELK integration
