Files
ComfyAssets-ComfyUI_PromptM…/py/lora_layout_cache.py
T
Vito Sansevero 88e44bb068 fix(lora): treat an offline Windows share as unvalidated and make cache tests portable (#362)
Review findings on phase 1: Windows raises FileNotFoundError with winerror
53/67 for an offline share, which is a temporary failure, not a missing file.
Test times are whole milliseconds (NTFS keeps 100 ns steps) and a file system
that rounds them skips; cleanup no longer ignores errors; tests added for
ValueError, NotADirectoryError, a failed reload, resolve failures and the
watched-file set.
2026-10-26 22:46:53 -07:00

183 lines
7.1 KiB
Python

"""A per-process cache of LoraManager's layout for the image hot paths (#362).
Every Library list, prompt detail, inspect, reveal and serve request needs the
LoRA allow-list (``ImagesMixin._lora_image_dirs``). Building it means finding
the LoraManager install, reading its plugin settings file and its settings
file, and resolving every folder. ``LayoutCache`` keeps the last result and
reuses it while all of these hold:
- the key (the configured install path, stripped) is the same;
- the entry is younger than ``MAX_AGE_SECONDS`` (monotonic clock);
- the plugin settings file and the settings file have the same signature
(``st_mtime_ns``, ``st_size``, or ``MISSING``) as when it was stored;
- the install and every stored media root still resolve to themselves (a
folder swapped for a symlink reloads, so the folder guard runs again).
A result is stored only when no watched file is "racy" (modified within
``RACY_SECONDS`` of the load, git's rule for racily clean index entries),
every watched file could be checked, the settings file was readable, and no
``clear()`` ran during the load. What each rule covers: signatures catch a
settings change on the next request; the racy rule catches a write during the
load, a half-written file and coarse timestamps; the maximum age bounds the
inputs no signature sees (``extra_model_paths.yaml``, environment, temporary
failures); ``clear()`` makes a finished import's new folders servable at once.
Hits and loads take no lock: a slow ``os.stat`` on a network share holds up
only its own request, and two threads that miss together both load (both
loads only read). A short lock guards the compare-and-store and the logging
state; no file I/O runs under it. Standard library only, so it is tested
without ComfyUI or LoraManager.
"""
import logging
import os
import threading
import time
from dataclasses import dataclass
from typing import Callable, Optional, Tuple
from .lora_manager_layout import UNREADABLE, LoraManagerLayout, _canonical
# A watched file modified this recently is not trusted: LoraManager writes its
# settings in place, and FAT/exFAT store modification times in 2 s steps.
RACY_SECONDS = 3
# Bounds what no signature sees (unwatched inputs, temporary failures).
MAX_AGE_SECONDS = 30
# The signature of a watched file that does not exist (a valid state).
MISSING = object()
# ERROR_BAD_NETPATH and ERROR_BAD_NET_NAME, which Windows raises as
# FileNotFoundError.
_OFFLINE_SHARE_ERRORS = frozenset({53, 67})
logger = logging.getLogger("prompt_manager.lora_layout_cache")
@dataclass(frozen=True)
class _Entry:
key: str
install: Optional[str]
layout: LoraManagerLayout
signatures: Tuple[Tuple[str, object], ...]
stored_at: float
class _CannotValidate(Exception):
"""A watched file could not be checked (not merely missing)."""
class LayoutCache:
"""At most one ``(install, layout)`` for the active LoraManager config."""
def __init__(
self,
resolve: Callable[[str], Optional[str]],
load: Callable[[Optional[str]], LoraManagerLayout],
*,
wall_ns: Callable[[], int] = time.time_ns,
monotonic: Callable[[], float] = time.monotonic,
stat=os.stat,
pathmod=os.path,
):
self._resolve = resolve
self._load = load
self._wall_ns = wall_ns
self._monotonic = monotonic
self._stat = stat
self._pathmod = pathmod
self._entry: Optional[_Entry] = None
self._generation = 0
self._lock = threading.Lock()
def get(self, configured: str) -> Tuple[Optional[str], LoraManagerLayout]:
"""``(install, layout)`` for the configured path ("" auto-detects)."""
key = (configured or "").strip()
entry = self._entry
if entry is not None and self._valid(entry, key):
return entry.install, entry.layout
with self._lock:
if entry is not None and self._entry is entry:
self._entry = None
generation = self._generation
install = self._resolve(key)
layout = self._load(install)
try:
signatures = tuple(
(path, self._signature(path)) for path in self._watched(install, layout)
)
except _CannotValidate:
return install, layout
if layout.error == UNREADABLE or self._racy(signatures, self._wall_ns()):
return install, layout
stored = _Entry(key, install, layout, signatures, self._monotonic())
with self._lock:
if self._generation == generation:
self._entry = stored
return install, layout
def clear(self) -> None:
"""Drop the entry; a load that started before this stores nothing."""
with self._lock:
self._entry = None
self._generation += 1
# ── validation ──────────────────────────────────────────────────
def _valid(self, entry: _Entry, key: str) -> bool:
if entry.key != key:
return False
if self._monotonic() - entry.stored_at >= MAX_AGE_SECONDS:
return False
try:
for path, signature in entry.signatures:
if self._signature(path) != signature:
return False
except _CannotValidate:
return False
folders = entry.layout.media_roots
if entry.install is not None:
folders = (entry.install,) + tuple(folders)
for folder in folders:
try:
if _canonical(folder, self._pathmod) != folder:
return False
except (OSError, ValueError):
return False
return True
def _watched(self, install, layout) -> Tuple[str, ...]:
"""The plugin settings file, then the settings file, each once."""
if install is None:
return ()
paths = [self._pathmod.join(install, "settings.json")]
if layout.settings_path is not None:
paths.append(str(layout.settings_path))
watched, seen = [], set()
for path in paths:
identity = self._pathmod.normcase(self._pathmod.abspath(path))
if identity not in seen:
seen.add(identity)
watched.append(path)
return tuple(watched)
def _signature(self, path: str):
try:
result = self._stat(path)
except (FileNotFoundError, NotADirectoryError) as error:
# Windows reports an offline share as "not found": that is a
# temporary failure, not a missing file.
if getattr(error, "winerror", None) in _OFFLINE_SHARE_ERRORS:
raise _CannotValidate(path) from error
return MISSING
except (OSError, ValueError) as error:
raise _CannotValidate(path) from error
return (result.st_mtime_ns, result.st_size)
@staticmethod
def _racy(signatures, now_ns: int) -> bool:
threshold = now_ns - RACY_SECONDS * 10**9
return any(
signature is not MISSING and signature[0] > threshold
for _path, signature in signatures
)