Files
Will Miao 255459f8f1 fix(scan): never register or hash a zero-byte model file
A file whose directory entry reports zero bytes hashes to the SHA256 of an
empty byte string. That value is shared by every unread or still-being-written
file: the library collapses them into one bogus duplicate group and every
member resolves to the same polluted remote entry (#1162).

- _calculate_sha256_sync returns "" when the read yields no bytes, so no
  caller can persist the placeholder as a real hash
- create_default_metadata refuses to create a sidecar for an empty file
- ModelScanner._process_model_file skips zero-byte files before loading or
  creating metadata, leaving them unmanaged until they have content
- a file whose metadata cannot be created no longer aborts the scan via assert
2026-10-25 19:33:13 +08:00

329 lines
12 KiB
Python

import asyncio
import hashlib
import json
import logging
import os
import struct
from typing import Any
from .constants import (
CARD_PREVIEW_WIDTH,
DEFAULT_HASH_CHUNK_SIZE_MB,
INVALID_AUTOV3_EMPTY_HASH,
MAX_SAFETENSORS_HEADER_BYTES,
PREVIEW_EXTENSIONS,
SUPPORTED_MEDIA_EXTENSIONS,
)
from .exif_utils import ExifUtils
from ..services.settings_manager import get_settings_manager
logger = logging.getLogger(__name__)
def _get_hash_chunk_size_bytes() -> int:
"""Return the chunk size used for hashing, in bytes."""
settings_manager = get_settings_manager()
chunk_size_mb = settings_manager.get("hash_chunk_size_mb", DEFAULT_HASH_CHUNK_SIZE_MB)
try:
chunk_size_value = float(chunk_size_mb)
except (TypeError, ValueError):
chunk_size_value = float(DEFAULT_HASH_CHUNK_SIZE_MB)
if chunk_size_value <= 0:
chunk_size_value = float(DEFAULT_HASH_CHUNK_SIZE_MB)
return max(1, int(chunk_size_value * 1024 * 1024))
async def calculate_sha256(file_path: str) -> str:
"""Calculate SHA256 hash of a file (full file content).
The blocking read+hash loop runs in a thread executor so callers awaiting
this coroutine never stall the aiohttp event loop — a multi-GB checkpoint
hash would otherwise freeze every HTTP endpoint and websocket for the
duration of the hash.
Uses ``posix_fadvise`` with ``POSIX_FADV_DONTNEED`` to avoid polluting the OS page
cache — critical on WSL where cached file pages live inside the VM and are not
accounted for in guest ``used`` memory, causing VmmemWSL to balloon.
On Windows/macOS where ``posix_fadvise`` is not available the hint is silently
skipped.
Returns ``""`` when the file contains no bytes at all: the SHA256 of an
empty byte string is not a model identity, and persisting it would fold
every unreadable/unfinished file into one bogus identity (issue #1162).
"""
loop = asyncio.get_running_loop()
return await loop.run_in_executor(None, _calculate_sha256_sync, file_path)
def _calculate_sha256_sync(file_path: str) -> str:
sha256_hash = hashlib.sha256()
chunk_size = _get_hash_chunk_size_bytes()
read_any = False
with open(file_path, "rb") as f:
fd = f.fileno()
for byte_block in iter(lambda: f.read(chunk_size), b""):
read_any = True
sha256_hash.update(byte_block)
# Evict pages after reading so the data doesn't linger in the kernel page
# cache — on WSL this otherwise appears as unreclaimable VmmemWSL growth.
# Guard against platforms (Windows, macOS) that lack posix_fadvise.
if hasattr(os, "posix_fadvise") and hasattr(os, "POSIX_FADV_DONTNEED"):
os.posix_fadvise(fd, 0, 0, os.POSIX_FADV_DONTNEED)
if not read_any:
# A zero-byte file (or a file that was still being created/truncated
# when the scan reached it) hashes to the empty-string digest. That
# value is shared by every such file, so it can never identify a
# model; report "no hash" instead of a poisonous identity.
logger.debug("No bytes read; skipping SHA256 for empty file %s", file_path)
return ""
return sha256_hash.hexdigest()
def calculate_autov2(file_path: str) -> str:
"""Calculate CivitAI AutoV2 hash.
AutoV2 is the first 10 characters of the full file SHA256.
Used by CivitAI as a shortened file identifier.
Reference: https://developer.civitai.com/site/reference/model-versions
"""
full_hash = hashlib.sha256()
chunk_size = _get_hash_chunk_size_bytes()
with open(file_path, "rb") as f:
for byte_block in iter(lambda: f.read(chunk_size), b""):
full_hash.update(byte_block)
return full_hash.hexdigest()[:10]
def read_safetensors_metadata(file_path: str) -> dict[str, Any]:
"""Read the ``__metadata__`` dict from a safetensors file header.
Safetensors file format:
- 8 bytes: header length (little-endian 64-bit)
- N bytes: UTF-8 JSON header
- The header JSON contains a ``__metadata__`` key holding arbitrary metadata.
Returns an empty dict if the file is not a valid safetensors file or has no
metadata.
"""
try:
with open(file_path, "rb") as f:
header_len_bytes = f.read(8)
if len(header_len_bytes) < 8:
return {}
header_len = struct.unpack("<Q", header_len_bytes)[0]
if header_len > MAX_SAFETENSORS_HEADER_BYTES:
return {}
header_bytes = f.read(header_len)
if len(header_bytes) < header_len:
return {}
header = json.loads(header_bytes.decode("utf-8"))
return header.get("__metadata__", {})
except (OSError, json.JSONDecodeError, UnicodeDecodeError, struct.error, MemoryError, Exception):
return {}
def calculate_autov3(file_path: str) -> str | None:
"""Calculate CivitAI AutoV3 hash from a safetensors file.
AutoV3 is extracted from the safetensors file's embedded metadata, not
computed from the file bytes directly. The orchestrator reads the
``sshs_model_hash`` (kohya-ss format) or ``modelspec.hash_sha256`` field
from the safetensors header and stores the first 12 characters.
The embedded hash itself is the SHA256 of the file after skipping the
8-byte header length + JSON header (a.k.a. the addnet hash / tensor-only
hash).
Reference:
- CivitAI DB trigger: ``SUBSTRING(NEW.hash FROM 1 FOR 12)``
- https://developer.civitai.com/site/reference/model-versions
Returns ``None`` when no AutoV3 hash can be determined (e.g. the file is
not safetensors, or the metadata doesn't contain a recognised hash field).
"""
metadata = read_safetensors_metadata(file_path)
if not metadata:
return None
embedded_hash = metadata.get("sshs_model_hash") or metadata.get("modelspec.hash_sha256")
if embedded_hash and isinstance(embedded_hash, str):
# OneTrainer writes modelspec.hash_sha256 with a "0x" prefix.
embedded_hash = embedded_hash.strip().removeprefix("0x").removeprefix("0X")
if len(embedded_hash) >= 12:
autov3 = embedded_hash[:12].lower()
# The empty-string SHA256 placeholder written by some repackaging
# tools is not a real hash; treat it as unavailable so broken
# models never share one bogus value.
if autov3 != INVALID_AUTOV3_EMPTY_HASH:
return autov3
return None
def detect_media_extension(
content: bytes | None,
headers: dict | None = None,
fallback_url: str | None = None,
media_type_hint: str | None = None,
default: str = ".jpg",
) -> str:
"""Determine a file extension from content magic bytes or headers.
CDNs (Civitai's ``optimized=true`` renditions in particular) re-encode
media regardless of the extension in the URL path, so the URL extension
must only be used as a fallback after content and headers.
Args:
content: File content bytes (only the first bytes are inspected).
headers: HTTP response headers.
fallback_url: Original URL for extension extraction.
media_type_hint: Optional media type hint from metadata (e.g. "video" or "image").
default: Extension returned when nothing else matches. Pass ``""`` to
treat unrecognized content as a detection failure.
"""
# Check magic bytes for common formats
if content:
if content.startswith(b'\xFF\xD8\xFF'):
return '.jpg'
elif content.startswith(b'\x89PNG\r\n\x1A\n'):
return '.png'
elif content.startswith(b'GIF87a') or content.startswith(b'GIF89a'):
return '.gif'
elif content.startswith(b'RIFF') and b'WEBP' in content[:12]:
return '.webp'
elif len(content) >= 12 and content[4:8] == b'ftyp' and b'avif' in content[8:24]:
return '.avif'
elif content.startswith(b'\x00\x00\x00\x0cJXL \x0d\x0a\x87\x0a'):
return '.jxl'
elif content.startswith(b'\x00\x00\x00\x18ftypmp4') or content.startswith(b'\x00\x00\x00\x20ftypmp4'):
return '.mp4'
elif content.startswith(b'\x1A\x45\xDF\xA3'):
return '.webm'
# Check Content-Type header
if headers:
content_type = headers.get('content-type', '').lower()
type_map = {
'image/jpeg': '.jpg',
'image/png': '.png',
'image/gif': '.gif',
'image/webp': '.webp',
'image/avif': '.avif',
'image/jxl': '.jxl',
'video/mp4': '.mp4',
'video/webm': '.webm',
'video/quicktime': '.mov'
}
if content_type in type_map:
return type_map[content_type]
# Fallback to URL extension if available
if fallback_url:
filename = os.path.basename(fallback_url.split('?')[0])
ext = os.path.splitext(filename)[1].lower()
if ext in SUPPORTED_MEDIA_EXTENSIONS['images'] or ext in SUPPORTED_MEDIA_EXTENSIONS['videos']:
return ext
# Use media type hint from metadata if available
if media_type_hint == "video":
return '.mp4'
# Default fallback
return default
def reconcile_media_extension(file_path: str) -> str:
"""Rename *file_path* when its bytes indicate a different media format.
Returns the final path: the renamed path when the sniffed extension is a
supported media extension that differs from the current one, otherwise
*file_path* unchanged.
"""
current_ext = os.path.splitext(file_path)[1].lower()
try:
with open(file_path, "rb") as f:
head = f.read(64)
except OSError:
return file_path
detected = detect_media_extension(head, default="")
if not detected or detected == current_ext:
return file_path
if {detected, current_ext} <= {".jpg", ".jpeg"}:
return file_path
supported = (
SUPPORTED_MEDIA_EXTENSIONS["images"] + SUPPORTED_MEDIA_EXTENSIONS["videos"]
)
if detected not in supported:
return file_path
new_path = os.path.splitext(file_path)[0] + detected
try:
os.replace(file_path, new_path)
except OSError:
return file_path
return new_path
def find_preview_file(base_name: str, dir_path: str) -> str:
"""Find preview file for given base name in directory.
Performs an exact-case check first (fast path), then falls back to a
case-insensitive scan so that files like ``model.WEBP`` or ``model.Png``
are discovered on case-sensitive filesystems.
"""
temp_extensions = PREVIEW_EXTENSIONS.copy()
# Add example extension for compatibility
# https://github.com/willmiao/ComfyUI-Lora-Manager/issues/225
# The preview image will be optimized to lora-name.webp, so it won't affect other logic
temp_extensions.append(".example.0.jpeg")
# Fast path: exact-case match
for ext in temp_extensions:
full_pattern = os.path.join(dir_path, f"{base_name}{ext}")
if os.path.exists(full_pattern):
return full_pattern.replace(os.sep, "/")
# Slow path: case-insensitive match for systems with mixed-case extensions
# (e.g. .WEBP, .Png, .JPG placed manually or by external tools)
try:
dir_entries = os.listdir(dir_path)
except OSError:
return ""
base_lower = base_name.lower()
for ext in temp_extensions:
target = f"{base_lower}{ext}" # ext is already lowercase
for entry in dir_entries:
if entry.lower() == target:
return os.path.join(dir_path, entry).replace(os.sep, "/")
return ""
def get_preview_extension(preview_path: str) -> str:
"""Get the complete preview extension from a preview file path
Args:
preview_path: Path to the preview file
Returns:
str: The complete extension (e.g., '.preview.png', '.png', '.webp')
"""
preview_path_lower = preview_path.lower()
# Check for compound extensions first (longer matches first)
for ext in sorted(PREVIEW_EXTENSIONS, key=len, reverse=True):
if preview_path_lower.endswith(ext.lower()):
return ext
return os.path.splitext(preview_path)[1]
def normalize_path(path: str) -> str:
"""Normalize file path to use forward slashes"""
return path.replace(os.sep, "/") if path else path