Added better logging

pkgs/clan-cli/clan_cli/webui/app.py

@@ -5,6 +5,7 @@ from fastapi.middleware.cors import CORSMiddleware
 from fastapi.routing import APIRoute
 from fastapi.staticfiles import StaticFiles
 
+
 from .assets import asset_path
 from .routers import flake, health, machines, root, utils, vms
 
@@ -35,7 +36,7 @@ def setup_app() -> FastAPI:
     app.add_exception_handler(
         utils.NixBuildException, utils.nix_build_exception_handler
     )
-
+    
     app.mount("/static", StaticFiles(directory=asset_path()), name="static")
 
     for route in app.routes:

pkgs/clan-cli/clan_cli/webui/assets.py

@@ -1,7 +1,39 @@
 import functools
 from pathlib import Path
+import logging
+
+log = logging.getLogger(__name__)
+
+def get_hash(string: str) -> str:
+    """
+    This function takes a string like '/nix/store/kkvk20b8zh8aafdnfjp6dnf062x19732-source'
+    and returns the hash part 'kkvk20b8zh8aafdnfjp6dnf062x19732' after '/nix/store/' and before '-source'.
+    """
+    # Split the string by '/' and get the last element
+    last_element = string.split('/')[-1]
+    # Split the last element by '-' and get the first element
+    hash_part = last_element.split('-')[0]
+    # Return the hash part
+    return hash_part
+
+
+def check_divergence(path: Path) -> None:
+    p = path.resolve()
+
+    log.info("Absolute web asset path: %s", p)
+    if not p.is_dir():
+        raise FileNotFoundError(p)
+
+    # Get the hash part of the path
+    gh = get_hash(str(p))
+
+    log.debug(f"Serving webui asset with hash {gh}")
+
 
 
 @functools.cache
 def asset_path() -> Path:
-    return Path(__file__).parent / "assets"
+    path = Path(__file__).parent / "assets"
+    log.debug("Serving assets from: %s", path)
+    check_divergence(path)
+    return path

pkgs/clan-cli/clan_cli/webui/routers/root.py

@@ -1,13 +1,15 @@
 import os
 from mimetypes import guess_type
 from pathlib import Path
-
+import logging
 from fastapi import APIRouter, Response
 
 from ..assets import asset_path
 
 router = APIRouter()
 
+log = logging.getLogger(__name__)
+
 
 @router.get("/{path_name:path}")
 async def root(path_name: str) -> Response:
@@ -16,6 +18,7 @@ async def root(path_name: str) -> Response:
     filename = Path(os.path.normpath(asset_path() / path_name))
 
     if not filename.is_relative_to(asset_path()):
+        log.error("Prevented directory traversal: %s", filename)
         # prevent directory traversal
         return Response(status_code=403)
 
@@ -23,6 +26,7 @@ async def root(path_name: str) -> Response:
         if filename.suffix == "":
             filename = filename.with_suffix(".html")
             if not filename.is_file():
+                log.error("File not found: %s", filename)
                 return Response(status_code=404)
 
     content_type, _ = guess_type(filename)