Files
LinedanceAfspiller/linedance-api/local/file_watcher.py
2026-04-11 00:38:04 +02:00

259 lines
8.9 KiB
Python

"""
file_watcher.py — Overvåger musikbiblioteker og holder SQLite opdateret.
Bruger watchdog til at reagere på fil-ændringer i realtid.
Kører fuld scan ved opstart for at fange ændringer lavet mens appen var lukket.
"""
import threading
import time
import logging
from pathlib import Path
from typing import Callable
try:
from watchdog.observers import Observer
from watchdog.events import (
FileSystemEventHandler,
FileCreatedEvent,
FileModifiedEvent,
FileDeletedEvent,
FileMovedEvent,
)
WATCHDOG_AVAILABLE = True
except ImportError:
WATCHDOG_AVAILABLE = False
print("Advarsel: watchdog ikke installeret — fil-overvågning deaktiveret")
from local.tag_reader import is_supported, read_tags, get_file_modified_at
from local.local_db import (
get_libraries, add_library, remove_library,
upsert_song, mark_song_missing,
get_all_song_paths_for_library, update_library_scan_time,
)
logger = logging.getLogger(__name__)
class MusicLibraryHandler(FileSystemEventHandler):
"""
Reagerer på ændringer i et musikbibliotek.
Kører i watchdog's baggrundstråd — DB-operationer er thread-safe via WAL.
"""
def __init__(self, library_id: int, on_change: Callable | None = None):
self.library_id = library_id
self.on_change = on_change # valgfrit callback til GUI-opdatering
self._debounce: dict[str, float] = {}
self._debounce_lock = threading.Lock()
def _debounced(self, path: str) -> bool:
"""
Forhindrer at samme fil behandles flere gange på kort tid.
Nogle programmer gemmer filer i flere trin (temp-fil → rename).
"""
now = time.time()
with self._debounce_lock:
last = self._debounce.get(path, 0)
if now - last < 1.5: # 1.5 sekunder cooldown
return False
self._debounce[path] = now
return True
def on_created(self, event):
if event.is_directory or not is_supported(event.src_path):
return
if self._debounced(event.src_path):
self._process_file(event.src_path)
def on_modified(self, event):
if event.is_directory or not is_supported(event.src_path):
return
if self._debounced(event.src_path):
self._process_file(event.src_path)
def on_deleted(self, event):
if event.is_directory or not is_supported(event.src_path):
return
logger.info(f"Fil slettet: {event.src_path}")
mark_song_missing(event.src_path)
if self.on_change:
self.on_change("deleted", event.src_path, None)
def on_moved(self, event):
if event.is_directory:
return
# Behandl som slet + opret
if is_supported(event.src_path):
mark_song_missing(event.src_path)
if is_supported(event.dest_path):
if self._debounced(event.dest_path):
self._process_file(event.dest_path)
def _process_file(self, path: str):
"""Læs tags og gem i SQLite."""
try:
logger.debug(f"Høster tags fra: {path}")
tags = read_tags(path)
tags["library_id"] = self.library_id
song_id = upsert_song(tags)
logger.info(f"Opdateret: {Path(path).name} ({len(tags.get('dances', []))} danse)")
if self.on_change:
self.on_change("upserted", path, song_id)
except Exception as e:
logger.error(f"Fejl ved behandling af {path}: {e}")
class LibraryWatcher:
"""
Styrer watchdog-observere for alle aktive musikbiblioteker.
Én instans per applikation.
"""
def __init__(self, on_change: Callable | None = None):
self.on_change = on_change
self._observer: Observer | None = None
self._running = False
def start(self):
"""Start overvågning af alle aktive biblioteker + kør fuld scan."""
if not WATCHDOG_AVAILABLE:
logger.warning("watchdog ikke tilgængelig — starter kun fuld scan")
self._full_scan_all()
return
self._observer = Observer()
libraries = get_libraries(active_only=True)
for lib in libraries:
path = Path(lib["path"])
if not path.exists():
logger.warning(f"Bibliotek findes ikke: {path}")
continue
handler = MusicLibraryHandler(lib["id"], self.on_change)
self._observer.schedule(handler, str(path), recursive=True)
logger.info(f"Overvåger: {path}")
self._observer.start()
self._running = True
# Fuld scan i baggrundstråd så GUI ikke blokeres
threading.Thread(target=self._full_scan_all, daemon=True).start()
def stop(self):
if self._observer and self._running:
self._observer.stop()
self._observer.join()
self._running = False
def add_library(self, path: str) -> int:
"""Tilføj et nyt bibliotek og start overvågning af det med det samme."""
library_id = add_library(path)
if self._observer and self._running:
handler = MusicLibraryHandler(library_id, self.on_change)
self._observer.schedule(handler, path, recursive=True)
logger.info(f"Tilføjet bibliotek: {path}")
# Scan det nye bibliotek i baggrunden
threading.Thread(
target=self._full_scan_library,
args=(library_id, path),
daemon=True,
).start()
return library_id
def remove_library(self, library_id: int):
"""Deaktiver bibliotek. Watchdog stopper automatisk ved næste restart."""
remove_library(library_id)
# Genstart observer for at fjerne watch (watchdog understøtter ikke unschedule by id)
if self._observer and self._running:
self._observer.unschedule_all()
self._reschedule_all()
def _reschedule_all(self):
"""Genplanlæg alle aktive biblioteker på observeren."""
for lib in get_libraries(active_only=True):
path = Path(lib["path"])
if path.exists():
handler = MusicLibraryHandler(lib["id"], self.on_change)
self._observer.schedule(handler, str(path), recursive=True)
def _full_scan_all(self):
"""Kør fuld scan på alle aktive biblioteker."""
for lib in get_libraries(active_only=True):
path = Path(lib["path"])
if path.exists():
self._full_scan_library(lib["id"], str(path))
def _full_scan_library(self, library_id: int, library_path: str):
"""
Sammenligner filer på disk med SQLite og synkroniserer forskelle.
Tre operationer:
1. Nye filer → indsæt i SQLite
2. Ændrede filer → opdater SQLite (baseret på fil-timestamp)
3. Forsvundne → marker som missing i SQLite
"""
logger.info(f"Fuld scan starter: {library_path}")
base = Path(library_path)
# Hvad SQLite kender til
known = get_all_song_paths_for_library(library_id)
# Hvad der faktisk er på disk
found_paths = set()
processed = 0
errors = 0
for file_path in base.rglob("*"):
if not file_path.is_file() or not is_supported(file_path):
continue
path_str = str(file_path)
found_paths.add(path_str)
disk_modified = get_file_modified_at(file_path)
# Ny fil eller ændret siden sidst
if path_str not in known or known[path_str] != disk_modified:
try:
tags = read_tags(file_path)
tags["library_id"] = library_id
upsert_song(tags)
processed += 1
if self.on_change:
self.on_change("upserted", path_str, None)
except Exception as e:
logger.error(f"Scan-fejl for {file_path}: {e}")
errors += 1
# Marker forsvundne filer
missing_count = 0
for known_path in known:
if known_path not in found_paths:
mark_song_missing(known_path)
missing_count += 1
if self.on_change:
self.on_change("deleted", known_path, None)
update_library_scan_time(library_id)
logger.info(
f"Scan færdig: {library_path}"
f"{processed} opdateret, {missing_count} mangler, {errors} fejl"
)
# ── Singleton til brug i appen ────────────────────────────────────────────────
_watcher: LibraryWatcher | None = None
def get_watcher(on_change: Callable | None = None) -> LibraryWatcher:
"""Returnerer den globale LibraryWatcher-instans."""
global _watcher
if _watcher is None:
_watcher = LibraryWatcher(on_change=on_change)
return _watcher