The /api/chat/stream_status handler did a membership test against
_active_streams followed by an indexed read of the same key. Between
those two ops, a sibling stream's finally block (or a stop / cleanup
path) can pop the entry, turning the indexed read into a KeyError that
bubbles up as a 500. The race is the exact one _stream_set was already
written to avoid; the comment on the helper at the top of the module
spells out why a single .get() is the right pattern here too.
Collapse the two-step into a single .get() call so the lookup either
returns the live record or None, and report 'detached' / 404 based on
that single read. No behavior change on the happy path; the failure
mode under concurrent stream cleanup is now handled deterministically.
Closes#658.
* feat(web-fetch): add web_fetch tool to read a specific URL's content
* test(web-fetch): add SSRF coverage and fail closed on empty DNS resolution
Add explicit SSRF regression tests for the web_fetch path covering
loopback, private LAN ranges, link-local/metadata, IPv6 private/local,
redirect-into-private, and unsupported schemes. Harden _public_http_url
to fail closed when a hostname resolves to no addresses.
chat_routes.py persisted a session's "mode" in three best-effort spots —
reading the current mode, writing the effective mode, and setting
research_pending on the stream path. Each opened a session with SessionLocal()
and called .close() as the LAST statement inside a try/except, so if anything
before close() raised (e.g. a SQLite "database is locked" under concurrent chat
streams) the except only logged and the connection was never returned to the
pool.
DATABASE_URL defaults to file-backed SQLite, whose engine uses SQLAlchemy's
default QueuePool (5 connections + 10 overflow). Repeated leaks on these hot
paths exhaust the pool; later requests then block for pool_timeout and fail
with "QueuePool limit ... reached", taking the app down until restart.
Move the logic into two best-effort helpers in core.database, next to the
existing session helpers (update_session_last_accessed, get_session_by_id):
- get_session_mode(session_id) -> Optional[str]
- set_session_mode(session_id, mode) -> bool
Both route through the existing get_db_session() context manager, which commits
on success, rolls back on error, and always closes in a finally, so the
connection is returned to the pool on every path. chat_routes.py now calls
these instead of hand-rolling sessions, also removing three copies of the same
try/except.
Add tests/test_session_mode_helpers.py: the helpers commit+close on success
and, on a mid-operation DB error, swallow + roll back + close (no leak). The
error-path tests fail against the old close()-inside-try pattern.
tanmayraut45