Two functions on the /api/session/handoff-summary hot path were opening
sqlite3.connect(...) inside a bare `with` statement, which commits the
transaction at scope exit but does NOT close the connection. Per-turn
invocations accumulated state.db / state.db-wal file descriptors and
CPython heap pages on long-lived worker threads, surfacing as the
multi-GB VmRSS and 6x duplicated state.db fds observed on the live
instance (D0 pre-restart baseline: VmRSS 1,334,248 kB, 55 fds; cold
baseline after restart: VmRSS 136,668 kB, 10 fds).
Wrap both call sites with contextlib.closing(...) (already imported and
used at seven other sites in the same files) so the connection is
closed deterministically:
- api/models.py :: count_conversation_rounds
- api/routes.py :: _persist_handoff_summary_to_state_db
Regression test:
tests/test_issue2233_sqlite_connection_leak.py loops both functions
20 times against a tmp state.db and asserts /proc/<pid>/fd count
does not grow more than 2. Linux-only via sys.platform skip.
D1 live soak against a freshly-built worktree server (port 8799,
isolated HERMES_HOME / HERMES_WEBUI_STATE_DIR) hitting
/api/session/handoff-summary 20 times:
fd_before = 5
fd_after = 5 (growth 0, threshold < 5)
vmrss_before = 52636 kB
vmrss_after = 52636 kB (growth 0 kB, threshold < 30 MB)
The patched fix curve trends below the leak curve.
Rollback: single git revert <this-sha> reverts both file edits.
Refs #2233.
