- Per-user SSE cap uses per-connection leases in a sorted set instead of
a shared INCR/DECR counter with a TTL. A stream that outlived the TTL
could let the counter expire, then decrement another stream's slot or
drive the count negative. Leases refresh while a stream sends frames
and age out when a stream dies without cleanup.
- Shielded cleanup is bounded per step: stream close and on_close in
ClosingStreamingResponse, unsubscribe and close in AsyncTopic, lease
release, and the replay-budget check, so a dead Redis connection can't
hold a request or a graceful shutdown.
- Artifact downloads send an ASCII filename plus an RFC 5987 filename*
for non-ASCII names, build headers before opening the file, and close
disk handles off the event loop.
- Type hints and docstrings on the new helpers.
Move GET /api/events, the remote-device command stream and artifact
downloads from Flask to Starlette routes mounted ahead of the Flask
catch-all. On Flask each held an a2wsgi threadpool slot for as long as
its response stayed open, and because uvicorn drops writes after a
client disconnects, a closed tab never released it.
- asgi_auth: one JWT/OIDC gate for Starlette routes; the chat reconnect
reader uses it too
- ClosingStreamingResponse closes the body iterator and releases the
SSE slot or file handle even when the client leaves before the first
frame
- AsyncTopic liveness probe replaces the sync client's socket_timeout
guard against half-open pub/sub sockets
- ASYNC_REDIS_MAX_CONNECTIONS sizes the async Redis pool; every open
stream holds a connection and redis-py defaults to 100
Alex