fix(session): serialize canonical file access (#5383)

This commit is contained in:
chengyongru
2026-08-14 10:32:17 +08:00
committed by GitHub
parent e3d1819a2b
commit e226242dfc
10 changed files with 262 additions and 77 deletions
+13 -16
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@@ -769,28 +769,25 @@ class MemoryStore:
return f"{prefix}\n\n{diff_body}"
@staticmethod
def prune_dream_sessions(sessions_dir: Path, *, keep: int = 10) -> None:
def prune_dream_sessions(sessions: SessionManager, *, keep: int = 10) -> None:
"""Remove the oldest Dream session files, keeping only the N most recent.
Only current base64url-encoded Dream session keys are considered.
Non-dream session files are never touched.
"""
dream_files: list[Path] = []
for path in sessions_dir.glob("*.jsonl"):
decoded_key = SessionManager.decode_storage_key(path.stem)
if decoded_key is not None and decoded_key.startswith("dream:"):
dream_files.append(path)
dream_files.sort(key=lambda p: p.stat().st_mtime)
if len(dream_files) <= keep:
return
with sessions.locked_session_files() as sessions_dir:
dream_files: list[tuple[Path, str]] = []
for path in sessions_dir.glob("*.jsonl"):
decoded_key = SessionManager.decode_storage_key(path.stem)
if decoded_key is not None and decoded_key.startswith("dream:"):
dream_files.append((path, decoded_key))
dream_files.sort(key=lambda item: item[0].stat().st_mtime)
to_remove = dream_files[: len(dream_files) - keep]
for path in to_remove:
try:
path.unlink()
logger.debug("Pruned old dream session: {}", path.stem)
except OSError:
logger.warning("Failed to prune dream session {}", path)
for path, key in dream_files[: max(0, len(dream_files) - keep)]:
if sessions.delete_session(key):
logger.debug("Pruned old dream session: {}", path.stem)
else:
logger.warning("Failed to prune dream session {}", path)
# ---------------------------------------------------------------------------
+1 -1
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@@ -566,7 +566,7 @@ def _run_gateway(
if sha:
logger.info("Dream commit: {}", sha)
store.compact_history()
prune_dream_sessions(agent.sessions.sessions_dir)
prune_dream_sessions(agent.sessions)
return None
# Heartbeat is a system job that checks HEARTBEAT.md for active tasks.
+1 -1
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@@ -490,7 +490,7 @@ async def cmd_dream(ctx: CommandContext) -> OutboundMessage:
if sha:
content += f" (commit {sha})"
store.compact_history()
prune_dream_sessions(loop.sessions.sessions_dir)
prune_dream_sessions(loop.sessions)
await loop.bus.publish_outbound(OutboundMessage(
channel=msg.channel, chat_id=msg.chat_id, content=content,
))
+56 -12
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@@ -9,12 +9,12 @@ import re
import secrets
import stat
from collections import OrderedDict
from contextlib import suppress
from contextlib import contextmanager, suppress
from copy import deepcopy
from dataclasses import dataclass, field
from datetime import datetime
from pathlib import Path
from typing import Any, Callable, Collection, Protocol, TypedDict, cast
from typing import Any, Callable, Collection, Generator, Protocol, TypedDict, cast
from weakref import WeakValueDictionary
from filelock import FileLock
@@ -65,6 +65,7 @@ _WORKSPACE_STATE_DIR = ".nanobot"
_WORKSPACE_ID_FILE = "workspace-id"
_WORKSPACE_ID_RE = re.compile(r"^[0-9a-f]{32}$")
_SESSION_MIGRATION_LOCK_TIMEOUT_SECONDS = 30
_SESSION_FILES_LOCK_FILENAME = ".session-files.lock"
_COPY_CHUNK_SIZE = 1024 * 1024
@@ -576,7 +577,17 @@ class JsonlSessionStore:
)
self.sessions_dir = ensure_dir(root / workspace_id)
self.legacy_sessions_dir = get_legacy_sessions_dir()
self._migrate_from_workspace(canonical_workspace)
self._session_files_lock = FileLock(
str(self.sessions_dir / _SESSION_FILES_LOCK_FILENAME)
)
with self._session_files_lock:
self._migrate_from_workspace(canonical_workspace)
@contextmanager
def locked_session_files(self) -> Generator[Path, None, None]:
"""Guard direct access to canonical session files in this directory."""
with self._session_files_lock:
yield self.sessions_dir
@staticmethod
def _fsync_directory(path: Path) -> None:
@@ -959,7 +970,7 @@ class JsonlSessionStore:
raise RuntimeError(f"refusing to restore into symlinked sessions directory: {old_dir}")
ensure_dir(old_dir)
with self._migration_lock:
with self._migration_lock, self._session_files_lock:
for src in self.sessions_dir.glob("*.jsonl"):
if self.session_key_from_path(src) is None:
continue
@@ -1021,6 +1032,10 @@ class JsonlSessionStore:
return self.legacy_sessions_dir / f"{self.safe_key(key)}.jsonl"
def load(self, key: str) -> Session | None:
with self._session_files_lock:
return self._load_unlocked(key)
def _load_unlocked(self, key: str) -> Session | None:
path = self.get_session_path(key)
if not path.exists():
return None
@@ -1086,7 +1101,7 @@ class JsonlSessionStore:
)
except _SESSION_DATA_ERRORS as e:
logger.warning("Failed to load session {}: {}", key, e)
repaired = self.repair(key)
repaired = self._repair_unlocked(key)
if repaired is not None:
logger.info(
"Recovered session {} from corrupt file ({} messages)",
@@ -1096,6 +1111,10 @@ class JsonlSessionStore:
return repaired
def repair(self, key: str, *, path: Path | None = None) -> Session | None:
with self._session_files_lock:
return self._repair_unlocked(key, path=path)
def _repair_unlocked(self, key: str, *, path: Path | None = None) -> Session | None:
if path is None:
path = self.get_session_path(key)
if not path.exists():
@@ -1188,11 +1207,15 @@ class JsonlSessionStore:
}
def save(self, session: Session, *, fsync: bool = False) -> None:
with self._session_files_lock:
self._save_unlocked(session, fsync=fsync)
def _save_unlocked(self, session: Session, *, fsync: bool = False) -> None:
path = self.get_session_path(session.key)
tmp_path = path.with_suffix(".jsonl.tmp")
tmp_path = path.with_name(f".{path.name}.{secrets.token_hex(8)}.tmp")
try:
with open(tmp_path, "w", encoding="utf-8") as f:
with open(tmp_path, "x", encoding="utf-8") as f:
metadata_line = {
"_type": "metadata",
"key": session.key,
@@ -1226,11 +1249,14 @@ class JsonlSessionStore:
raise
finally:
os.close(fd)
except BaseException:
finally:
tmp_path.unlink(missing_ok=True)
raise
def delete(self, key: str) -> bool:
with self._session_files_lock:
return self._delete_unlocked(key)
def _delete_unlocked(self, key: str) -> bool:
paths = [
self.get_session_path(key),
self.get_legacy_lossy_path(key),
@@ -1248,6 +1274,10 @@ class JsonlSessionStore:
return deleted
def read(self, key: str) -> SessionPayload | None:
with self._session_files_lock:
return self._read_unlocked(key)
def _read_unlocked(self, key: str) -> SessionPayload | None:
path = self.get_session_path(key)
if not path.exists():
return None
@@ -1297,13 +1327,17 @@ class JsonlSessionStore:
}
except _SESSION_DATA_ERRORS as e:
logger.warning("Failed to read session {}: {}", key, e)
repaired = self.repair(key, path=path)
repaired = self._repair_unlocked(key, path=path)
if repaired is not None:
logger.info("Recovered read-only session view {} from corrupt file", key)
return self.session_payload(repaired)
return None
def read_metadata(self, key: str) -> SessionMetadataPayload | None:
with self._session_files_lock:
return self._read_metadata_unlocked(key)
def _read_metadata_unlocked(self, key: str) -> SessionMetadataPayload | None:
path = self.get_session_path(key)
if not path.exists():
return None
@@ -1338,7 +1372,7 @@ class JsonlSessionStore:
return None
except _SESSION_DATA_ERRORS as e:
logger.warning("Failed to read session metadata {}: {}", key, e)
repaired = self.repair(key, path=path)
repaired = self._repair_unlocked(key, path=path)
if repaired is not None:
logger.info("Recovered read-only session metadata {} from corrupt file", key)
return {
@@ -1350,6 +1384,10 @@ class JsonlSessionStore:
return None
def list_sessions(self) -> list[SessionInfo]:
with self._session_files_lock:
return self._list_sessions_unlocked()
def _list_sessions_unlocked(self) -> list[SessionInfo]:
sessions: list[SessionInfo] = []
for path in self.sessions_dir.glob("*.jsonl"):
@@ -1427,7 +1465,7 @@ class JsonlSessionStore:
except FileNotFoundError:
continue
except _SESSION_DATA_ERRORS:
repaired = self.repair(storage_key, path=path)
repaired = self._repair_unlocked(storage_key, path=path)
if repaired is not None:
sessions.append(
{
@@ -1536,6 +1574,12 @@ class SessionManager:
"""Legacy global session path (~/.nanobot/sessions/)."""
return self._jsonl_store.get_legacy_session_path(key)
@contextmanager
def locked_session_files(self) -> Generator[Path, None, None]:
"""Guard exceptional direct access to canonical JSONL files."""
with self._jsonl_store.locked_session_files() as sessions_dir:
yield sessions_dir
def get_or_create(self, key: str) -> Session:
"""
Get an existing session or create a new one.
+12 -10
View File
@@ -10,6 +10,7 @@ from __future__ import annotations
import json
import os
import re
import secrets
from datetime import datetime
from pathlib import Path
from typing import Any, cast
@@ -56,12 +57,13 @@ _TRANSCRIPT_NON_ANSWER_KINDS = {"progress", "reasoning", "tool_hint"}
def list_webui_sessions(session_manager: SessionManager) -> list[dict[str, Any]]:
"""Return session rows for the WebUI sidebar, backed by a rebuildable cache."""
rows, changed = _reconcile_index(session_manager)
if changed:
try:
_write_index_rows(session_manager.sessions_dir, rows)
except Exception as e:
logger.debug("Failed to write WebUI session list index: {}", e)
with session_manager.locked_session_files():
rows, changed = _reconcile_index(session_manager)
if changed:
try:
_write_index_rows(session_manager.sessions_dir, rows)
except Exception as e:
logger.debug("Failed to write WebUI session list index: {}", e)
sessions = [
_public_row(session_manager.sessions_dir, get_webui_dir(), row)
for row in rows
@@ -169,14 +171,14 @@ def _read_index_rows(sessions_dir: Path) -> list[dict[str, Any]] | None:
def _write_index_rows(sessions_dir: Path, rows: list[dict[str, Any]]) -> None:
path = _index_path(sessions_dir)
tmp_path = path.with_suffix(".json.tmp")
tmp_path = path.with_name(f"{path.name}.{secrets.token_hex(8)}.tmp")
data = {"version": _INDEX_VERSION, "sessions": rows}
try:
tmp_path.write_text(json.dumps(data, ensure_ascii=False) + "\n", encoding="utf-8")
with open(tmp_path, "x", encoding="utf-8") as file:
file.write(json.dumps(data, ensure_ascii=False) + "\n")
os.replace(tmp_path, path)
except BaseException:
finally:
tmp_path.unlink(missing_ok=True)
raise
def _file_signature(path: Path) -> dict[str, int]:
+24 -13
View File
@@ -29,8 +29,11 @@ class TestPruneDreamSessions:
import os
import time
sessions_dir = tmp_path / "sessions"
sessions_dir.mkdir()
manager = SessionManager(
tmp_path / "workspace",
sessions_root=tmp_path / "runtime",
)
sessions_dir = manager.sessions_dir
base_time = time.time() - 100
dream_paths = []
@@ -50,7 +53,7 @@ class TestPruneDreamSessions:
normal_path = sessions_dir / "telegram_123.jsonl"
normal_path.write_text('{"_type": "metadata"}\n', encoding="utf-8")
MemoryStore.prune_dream_sessions(sessions_dir, keep=10)
MemoryStore.prune_dream_sessions(manager, keep=10)
assert [path.exists() for path in dream_paths] == [False] * 5 + [True] * 10
assert normal_path.exists()
@@ -59,8 +62,11 @@ class TestPruneDreamSessions:
import os
import time
sessions_dir = tmp_path / "sessions"
sessions_dir.mkdir()
manager = SessionManager(
tmp_path / "workspace",
sessions_root=tmp_path / "runtime",
)
sessions_dir = manager.sessions_dir
base_time = time.time() - 100
current_paths = []
@@ -81,24 +87,29 @@ class TestPruneDreamSessions:
)
os.utime(legacy_path, (base_time - 1, base_time - 1))
MemoryStore.prune_dream_sessions(sessions_dir, keep=1)
MemoryStore.prune_dream_sessions(manager, keep=1)
assert [path.exists() for path in current_paths] == [False, True]
assert legacy_path.exists()
def test_noop_when_under_limit(self, tmp_path):
sessions_dir = tmp_path / "sessions"
sessions_dir.mkdir()
manager = SessionManager(
tmp_path / "workspace",
sessions_root=tmp_path / "runtime",
)
sessions_dir = manager.sessions_dir
for i in range(3):
key = f"dream:20260528-{100000 + i:06d}"
path = sessions_dir / f"{SessionManager._storage_key(key)}.jsonl"
path.write_text("{}", encoding="utf-8")
MemoryStore.prune_dream_sessions(sessions_dir, keep=10)
MemoryStore.prune_dream_sessions(manager, keep=10)
assert len(list(sessions_dir.glob("*.jsonl"))) == 3
def test_empty_dir_noop(self, tmp_path):
sessions_dir = tmp_path / "sessions"
sessions_dir.mkdir()
MemoryStore.prune_dream_sessions(sessions_dir, keep=10)
assert list(sessions_dir.iterdir()) == []
manager = SessionManager(
tmp_path / "workspace",
sessions_root=tmp_path / "runtime",
)
MemoryStore.prune_dream_sessions(manager, keep=10)
assert list(manager.sessions_dir.glob("*.jsonl")) == []
+40 -9
View File
@@ -4,6 +4,9 @@ import json
from datetime import datetime
from pathlib import Path
import pytest
from filelock import Timeout
from nanobot.providers.base import ProviderConversationState
from nanobot.session.manager import Session, SessionManager
@@ -37,14 +40,23 @@ class TestAtomicSave:
tmp_files = list(mgr.sessions_dir.glob("*.tmp"))
assert tmp_files == []
def test_tmp_file_cleaned_up_on_write_failure(self, tmp_path: Path):
def test_unique_tmp_file_cleaned_up_on_write_failure(
self,
tmp_path: Path,
monkeypatch: pytest.MonkeyPatch,
):
mgr = SessionManager(tmp_path)
session = Session(key="test:fail")
path = mgr._get_session_path("test:fail")
tmp_path_file = path.with_suffix(".jsonl.tmp")
stale_shared_tmp = path.with_suffix(".jsonl.tmp")
unique_tmp = path.with_name(f".{path.name}.save-failure.tmp")
path.parent.mkdir(parents=True, exist_ok=True)
tmp_path_file.write_text("stale")
stale_shared_tmp.write_text("stale", encoding="utf-8")
monkeypatch.setattr(
"nanobot.session.manager.secrets.token_hex",
lambda _length: "save-failure",
)
class BadMessage:
def __init__(self, data):
@@ -64,13 +76,17 @@ class TestAtomicSave:
]
import unittest.mock
with unittest.mock.patch("nanobot.session.manager.json.dumps", side_effect=failing_dumps):
try:
mgr.save(session)
except OSError:
pass
with (
unittest.mock.patch(
"nanobot.session.manager.json.dumps",
side_effect=failing_dumps,
),
pytest.raises(OSError, match="simulated disk full"),
):
mgr.save(session)
assert not tmp_path_file.exists()
assert not unique_tmp.exists()
assert stale_shared_tmp.read_text(encoding="utf-8") == "stale"
def test_overwrite_preserves_latest_data(self, tmp_path: Path):
mgr = SessionManager(tmp_path)
@@ -102,6 +118,21 @@ class TestAtomicSave:
for i in range(5):
assert loaded.messages[i]["content"] == f"msg{i}"
def test_managers_for_same_directory_coordinate_saves(self, tmp_path: Path):
workspace = tmp_path / "workspace"
sessions_root = tmp_path / "runtime"
owner = SessionManager(workspace, sessions_root=sessions_root)
peer = SessionManager(workspace, sessions_root=sessions_root)
assert owner.sessions_dir == peer.sessions_dir
session = Session(key="test:peer-manager")
peer._jsonl_store._session_files_lock.timeout = 0
with owner.locked_session_files(), pytest.raises(Timeout):
peer.save(session)
peer.save(session)
assert peer._get_session_path(session.key).is_file()
def test_provider_state_round_trips_in_private_record_only(self, tmp_path: Path):
mgr = SessionManager(tmp_path)
secret = "encrypted-reasoning-blob"
+12 -12
View File
@@ -16,6 +16,7 @@ from nanobot.command.builtin import (
cmd_dream_restore,
)
from nanobot.command.router import CommandContext
from nanobot.session.manager import SessionManager
from nanobot.utils.gitstore import CommitInfo
@@ -107,6 +108,13 @@ class _FakeBus:
self.outbound.append(message)
def _make_sessions(tmp_path) -> SessionManager:
return SessionManager(
tmp_path / "workspace",
sessions_root=tmp_path / "runtime",
)
def _make_ctx(raw: str, git: _FakeGit, *, args: str = "", last_dream_cursor: int = 1) -> CommandContext:
msg = InboundMessage(channel="cli", sender_id="u1", chat_id="direct", content=raw)
store = _FakeStore(git, last_dream_cursor=last_dream_cursor)
@@ -118,12 +126,10 @@ def _make_dream_ctx(tmp_path) -> tuple[CommandContext, _FakeBus]:
msg = InboundMessage(channel="cli", sender_id="u1", chat_id="direct", content="/dream")
store = _FakeStore(_FakeGit(initialized=False), dream_prompt_result=None)
bus = _FakeBus()
sessions_dir = tmp_path / "sessions"
sessions_dir.mkdir()
loop = SimpleNamespace(
bus=bus,
context=SimpleNamespace(memory=store, timezone="UTC"),
sessions=SimpleNamespace(sessions_dir=sessions_dir),
sessions=_make_sessions(tmp_path),
)
ctx = CommandContext(msg=msg, session=None, key=msg.session_key, raw="/dream", args="", loop=loop)
return ctx, bus
@@ -169,13 +175,11 @@ async def test_dream_internal_run_silences_progress(tmp_path) -> None:
metadata={"_stop_reason": "completed"},
)
sessions_dir = tmp_path / "sessions"
sessions_dir.mkdir()
dream_runtime = object()
loop = SimpleNamespace(
bus=bus,
context=SimpleNamespace(memory=store, timezone="UTC"),
sessions=SimpleNamespace(sessions_dir=sessions_dir),
sessions=_make_sessions(tmp_path),
process_direct=process_direct,
dream_runtime=lambda: dream_runtime,
)
@@ -224,12 +228,10 @@ def _build_runnable_dream(
)
bus = _FakeBus()
sessions_dir = tmp_path / "sessions"
sessions_dir.mkdir()
loop = SimpleNamespace(
bus=bus,
context=SimpleNamespace(memory=store, timezone="UTC"),
sessions=SimpleNamespace(sessions_dir=sessions_dir),
sessions=_make_sessions(tmp_path),
process_direct=process_direct,
dream_runtime=lambda: None,
)
@@ -311,12 +313,10 @@ async def test_dream_noop_batch_unlocks_following_history(tmp_path) -> None:
msg = InboundMessage(channel="cli", sender_id="u1", chat_id="direct", content="/dream")
bus = _FakeBus()
sessions_dir = tmp_path / "sessions"
sessions_dir.mkdir()
loop = SimpleNamespace(
bus=bus,
context=SimpleNamespace(memory=store, timezone="UTC"),
sessions=SimpleNamespace(sessions_dir=sessions_dir),
sessions=_make_sessions(tmp_path),
process_direct=process_direct,
dream_runtime=lambda: None,
)
+5 -3
View File
@@ -6,7 +6,7 @@ import errno
import os
import sys
from pathlib import Path
from unittest.mock import patch
from unittest.mock import call, patch
import pytest
@@ -65,6 +65,7 @@ class TestSaveFsync:
session.add_message("user", "hello")
directory_fd = 987654
with (
manager.locked_session_files(),
patch("nanobot.session.manager.os.open", return_value=directory_fd) as open_dir,
patch(
"nanobot.session.manager.os.fsync",
@@ -76,7 +77,7 @@ class TestSaveFsync:
assert manager._get_session_path(session.key).exists()
open_dir.assert_called_once_with(str(manager.sessions_dir), os.O_RDONLY)
close_dir.assert_called_once_with(directory_fd)
assert close_dir.call_args_list.count(call(directory_fd)) == 1
def test_save_propagates_other_directory_fsync_errors(
self, manager: SessionManager
@@ -85,6 +86,7 @@ class TestSaveFsync:
session = manager.get_or_create("test:directory-fsync-io-error")
directory_fd = 987654
with (
manager.locked_session_files(),
patch("nanobot.session.manager.os.open", return_value=directory_fd),
patch(
"nanobot.session.manager.os.fsync",
@@ -95,7 +97,7 @@ class TestSaveFsync:
):
manager.save(session, fsync=True)
close_dir.assert_called_once_with(directory_fd)
assert close_dir.call_args_list.count(call(directory_fd)) == 1
class TestFlushAll:
+98
View File
@@ -3,6 +3,8 @@ from __future__ import annotations
import io
import json
import os
import threading
from concurrent.futures import ThreadPoolExecutor
from datetime import datetime
from pathlib import Path
@@ -50,6 +52,20 @@ def test_webui_session_list_reuses_valid_index_without_scanning_files(
assert rows[0]["model_preset"] == "fast"
def test_webui_session_index_uses_unique_temp_file(tmp_path: Path) -> None:
manager = SessionManager(tmp_path)
session = manager.get_or_create("websocket:unique-index-temp")
session.add_message("user", "hello")
manager.save(session)
stale_shared_tmp = manager.sessions_dir / ".webui_session_index.json.tmp"
stale_shared_tmp.write_text("stale", encoding="utf-8")
assert list_webui_sessions(manager)[0]["preview"] == "hello"
assert stale_shared_tmp.read_text(encoding="utf-8") == "stale"
assert not list(manager.sessions_dir.glob(".webui_session_index.json.*.tmp"))
def test_webui_session_list_indexes_workspace_scope_and_preserves_null(
tmp_path: Path,
) -> None:
@@ -133,6 +149,88 @@ def test_webui_session_list_does_not_cache_old_snapshot_with_new_signature(
assert session_list_index.indexed_workspace_scope(second)[1]["access_mode"] == "restricted"
def test_webui_session_scan_does_not_overlap_session_save(
tmp_path: Path,
monkeypatch: pytest.MonkeyPatch,
) -> None:
manager = SessionManager(
tmp_path / "workspace",
sessions_root=tmp_path / "runtime",
)
session = manager.get_or_create("websocket:windows-reader")
session.add_message("user", "before")
manager.save(session)
session_path = manager._get_session_path(session.key)
session.messages[0]["content"] = "after"
reader_open = threading.Event()
release_reader = threading.Event()
save_started = threading.Event()
save_lock_attempted = threading.Event()
write_entered = threading.Event()
original_open = open
store = manager._jsonl_store
original_acquire = store._session_files_lock.acquire
original_save_unlocked = store._save_unlocked
class BlockingReader:
def __init__(self, file):
self.file = file
def __enter__(self):
entered = self.file.__enter__()
reader_open.set()
if not release_reader.wait(5):
raise AssertionError("timed out waiting to release the session reader")
return entered
def __exit__(self, *args):
try:
return self.file.__exit__(*args)
finally:
reader_open.clear()
def blocking_open(path, *args, **kwargs):
file = original_open(path, *args, **kwargs)
if Path(path) == session_path:
return BlockingReader(file)
return file
def observed_acquire(*args, **kwargs):
if save_started.is_set():
save_lock_attempted.set()
return original_acquire(*args, **kwargs)
def observed_save_unlocked(session, *, fsync=False):
write_entered.set()
assert not reader_open.is_set(), "save entered while the canonical file was open"
return original_save_unlocked(session, fsync=fsync)
monkeypatch.setattr(session_list_index, "open", blocking_open, raising=False)
monkeypatch.setattr(store._session_files_lock, "acquire", observed_acquire)
monkeypatch.setattr(store, "_save_unlocked", observed_save_unlocked)
def save_session() -> None:
save_started.set()
manager.save(session)
with ThreadPoolExecutor(max_workers=2) as executor:
list_future = executor.submit(list_webui_sessions, manager)
try:
assert reader_open.wait(5)
save_future = executor.submit(save_session)
assert save_lock_attempted.wait(5)
assert not write_entered.is_set()
finally:
release_reader.set()
assert list_future.result(timeout=5)[0]["preview"] == "before"
save_future.result(timeout=5)
assert write_entered.is_set()
assert list_webui_sessions(manager)[0]["preview"] == "after"
def test_webui_session_list_rejects_invalid_internal_model_preset_metadata(
tmp_path: Path,
) -> None: