Files
nanobot/tests/session/test_session_cache.py
T
KDBandXubin Ren d35f99abfc fix(session): bound the in-memory session cache
Keep only 128 recently used sessions strongly cached while retaining weak references to evicted sessions still owned by active callers. This bounds idle memory growth without allowing duplicate live Session objects or skipping shutdown flushes.

Add LRU, lifecycle, SDK, and flush regression coverage.

Refs #4786
2026-07-18 17:37:07 +08:00

76 lines
2.3 KiB
Python

import gc
import weakref
from nanobot.session.manager import SESSION_CACHE_MAX_SIZE, SessionManager
def _bounded_manager(tmp_path, limit: int) -> SessionManager:
manager = SessionManager(tmp_path)
manager._max_cached_sessions = limit
return manager
def test_default_session_cache_is_bounded(tmp_path) -> None:
manager = SessionManager(tmp_path)
for index in range(SESSION_CACHE_MAX_SIZE + 1):
manager.get_or_create(f"test:{index}")
assert len(manager._cache) == SESSION_CACHE_MAX_SIZE
def test_session_cache_releases_inactive_lru_entries(tmp_path) -> None:
manager = _bounded_manager(tmp_path, 1)
first = manager.get_or_create("test:first")
first.add_message("user", "persist me")
manager.save(first)
first_ref = weakref.ref(first)
second = manager.get_or_create("test:second")
manager.save(second)
del first
gc.collect()
assert len(manager._cache) == 1
assert first_ref() is None
assert manager.get_or_create("test:first").messages[0]["content"] == "persist me"
def test_session_cache_keeps_identity_for_evicted_active_sessions(tmp_path) -> None:
manager = _bounded_manager(tmp_path, 1)
active = manager.get_or_create("test:active")
manager.save(active)
manager.save(manager.get_or_create("test:other"))
assert manager.get_or_create("test:active") is active
def test_session_cache_refreshes_lru_order_on_access(tmp_path) -> None:
manager = _bounded_manager(tmp_path, 2)
manager.save(manager.get_or_create("test:first"))
manager.save(manager.get_or_create("test:second"))
manager.get_or_create("test:first")
manager.save(manager.get_or_create("test:third"))
assert list(manager._cache) == ["test:first", "test:third"]
def test_flush_all_includes_live_sessions_outside_strong_cache(tmp_path, monkeypatch) -> None:
manager = _bounded_manager(tmp_path, 1)
active = manager.get_or_create("test:active")
manager.save(active)
manager.save(manager.get_or_create("test:other"))
saved: list[tuple[str, bool]] = []
original_save = manager.save
def recording_save(session, *, fsync=False):
saved.append((session.key, fsync))
original_save(session, fsync=fsync)
monkeypatch.setattr(manager, "save", recording_save)
assert manager.flush_all() == 2
assert set(saved) == {("test:active", True), ("test:other", True)}