Files
ComfyUI-Lora-Manager/py/middleware/csp_middleware.py
Will Miao 74bfd397aa feat: add CSP middleware to allow remote media previews, fixes #710, see #715
Introduce `relax_csp_for_remote_media` middleware that modifies Content Security Policy headers to permit loading media from trusted external domains (Civitai and Genur). This is necessary for LoRA Manager UI previews when ComfyUI runs with `--disable-api-nodes`, which otherwise blocks remote images and videos. The middleware is inserted after ComfyUI's `block_external_middleware` to properly extend the restrictive CSP header.
2025-12-09 10:37:35 +08:00

66 lines
2.1 KiB
Python

"""Middleware helpers for adjusting Content Security Policy headers."""
from typing import Awaitable, Callable, Dict, List
from aiohttp import web
REMOTE_MEDIA_SOURCES = (
"https://image.civitai.com",
"https://img.genur.art",
)
@web.middleware
async def relax_csp_for_remote_media(
request: web.Request, handler: Callable[[web.Request], Awaitable[web.StreamResponse]]
) -> web.StreamResponse:
"""Allow LoRA Manager media previews to load from trusted remote domains.
When ComfyUI is started with ``--disable-api-nodes`` it injects a restrictive
``Content-Security-Policy`` header that blocks remote images and videos. The
LoRA Manager UI legitimately needs to fetch previews from Civitai and Genur,
so this middleware augments the existing CSP to whitelist those hosts while
preserving all other directives.
"""
response: web.StreamResponse = await handler(request)
header_value = response.headers.get("Content-Security-Policy")
if not header_value:
return response
directive_order: List[str] = []
directives: Dict[str, List[str]] = {}
for raw_directive in header_value.split(";"):
directive = raw_directive.strip()
if not directive:
continue
parts = directive.split()
name, values = parts[0], parts[1:]
if name not in directive_order:
directive_order.append(name)
directives[name] = values
def merge_sources(name: str, sources: List[str], defaults: List[str] | None = None) -> None:
existing = directives.get(name, list(defaults or []))
for source in sources:
if source not in existing:
existing.append(source)
directives[name] = existing
if name not in directive_order:
directive_order.append(name)
merge_sources("img-src", list(REMOTE_MEDIA_SOURCES))
merge_sources("media-src", ["'self'", *REMOTE_MEDIA_SOURCES], defaults=["'self'"])
updated_header = "; ".join(
f"{name} {' '.join(directives[name])}".rstrip() for name in directive_order
)
response.headers["Content-Security-Policy"] = f"{updated_header};"
return response