Fix watcher sync loop when auto-watch is enabled

.gitignore

@@ -62,6 +62,9 @@ local_settings.py
 db.sqlite3
 db.sqlite3-journal
 
+# App runtime logs
+app/logs/
+
 # Flask stuff:
 instance/
 .webassets-cache
@@ -180,4 +183,7 @@ cython_debug/
 # data
 data/*
 playlists/*
-docker-compose.yml
+docker-compose.yml
+
+# Local dev config may contain Plex token
+app/config.json

app/config.json

@@ -1,29 +0,0 @@
-{
-    "theme": "auto",
-    "token": "",
-    "server_url": "",
-    "server_scheme": "http",
-    "server_port": "32400",
-    "timeout": 9,
-    "library_name": "",
-    "sync_mode": "local_force",
-    "path_rules": [],
-    "path_mapping": {
-        "mode": "SIMPLE",
-        "simple": [],
-        "regex": {
-            "local_pre": [],
-            "local_post": [],
-            "remote_pre": [],
-            "remote_post": []
-        }
-    },
-    "schedule_mode": "DISABLED",
-    "schedule_cron": "",
-    "schedule_daily_time": "00:00",
-    "schedule_weekly_days": [0],
-    "schedule_weekly_time": "00:00",
-    "schedule_auto_watch": false,
-    "backup_enabled": false,
-    "backup_retention_count": 5
-}

app/utils/backup.py

@@ -1,5 +1,7 @@
 import os
 import zipfile
+import hashlib
+import re
 from datetime import datetime
 from typing import List
 from app.utils.logger import logger
@@ -19,6 +21,28 @@ BACKUP_DIR = os.path.abspath(
 )
 
 
+def _safe_zip_entry_name(name: str, extension: str = ".m3u8") -> str:
+    """Return a safe zip entry filename.
+
+    Prevents zip-slip style paths and avoids problematic characters.
+    """
+
+    original = (name or "").strip()
+    base = os.path.basename(original)
+    base = re.sub(r"[\x00-\x1f\x7f]", "_", base)
+    invalid = set('<>:"/\\|?*')
+    cleaned = "".join(("_" if ch in invalid else ch) for ch in base).strip().strip(". ")
+    if not cleaned:
+        cleaned = "playlist"
+
+    cleaned = cleaned[:160].rstrip().strip(". ")
+    if cleaned != original:
+        digest = hashlib.sha1(original.encode("utf-8", errors="ignore")).hexdigest()[:8]
+        cleaned = f"{cleaned}__{digest}"
+
+    return f"{cleaned}{extension}"
+
+
 def ensure_backup_dir():
     """Ensure the backup directory exists."""
     if not os.path.exists(BACKUP_DIR):
@@ -118,7 +142,7 @@ def backup_local_playlists(local_path: str) -> str | None:
                 
                 # Get the playlist name without extension and add .m3u8 extension
                 playlist_name = os.path.splitext(entry.name)[0]
-                archive_name = f"{playlist_name}.m3u8"
+                archive_name = _safe_zip_entry_name(playlist_name)
                 
                 # Write to zip
                 zipf.writestr(archive_name, content)
@@ -217,7 +241,7 @@ def backup_cloud_playlists(library_name: str) -> str | None:
                     
                     if len(lines) > 1:  # More than just #EXTM3U
                         content = "\n".join(lines)
-                        archive_name = f"{playlist.title}.m3u8"
+                        archive_name = _safe_zip_entry_name(getattr(playlist, "title", "playlist"))
                         zipf.writestr(archive_name, content)
                         playlist_count += 1
                         

app/utils/config.py

@@ -2,6 +2,25 @@ import json
 import os
 from app.utils.logger import logger
 
+
+def _redact_for_log(value: object) -> object:
+    if not isinstance(value, dict):
+        return value
+    redacted = dict(value)
+    for key in ("token", "password"):
+        if key in redacted and redacted.get(key):
+            redacted[key] = "***"
+    return redacted
+
+
+def _redact_server_config_dict(state: dict) -> dict:
+    if not isinstance(state, dict):
+        return {}
+    redacted = dict(state)
+    if redacted.get("token"):
+        redacted["token"] = "***"
+    return redacted
+
 DEFAULT_SYNC_MODE = "merge_local_primary"
 LOCAL_PLAYLISTS_FOLDER = "playlists"
 DEFAULT_PATH_MAPPING = {
@@ -62,7 +81,7 @@ class ServerConfig:
         try:
             with open(CONFIG_PATH, "r", encoding="utf-8") as f:
                 config = json.load(f)
-            logger.debug(f"Loaded server config: {config}")
+            logger.debug(f"Loaded server config: {_redact_for_log(config)}")
         except FileNotFoundError:
             # 如果配置文件不存在，使用默认值
             self.save()
@@ -110,7 +129,7 @@ class ServerConfig:
         self.backup_enabled = config.get("backup_enabled", False)
         self.backup_retention_count = config.get("backup_retention_count", 5)
         logger.info(f"Server config loaded.")
-        logger.debug(f"Current server config: {self.__dict__}")
+        logger.debug(f"Current server config: {_redact_server_config_dict(self.__dict__)}")
 
     def save(self):
         _ensure_parent_dir(CONFIG_PATH)
@@ -137,7 +156,7 @@ class ServerConfig:
         with open(CONFIG_PATH, "w", encoding="utf-8") as f:
             json.dump(config, f, indent=4, ensure_ascii=False)
         logger.info(f"Server config saved.")
-        logger.debug(f"Saved server config: {config}")
+        logger.debug(f"Saved server config: {_redact_for_log(config)}")
 
     def set_url(self, url: str) -> None:
         self.url = url

app/utils/local_playlist.py

@@ -78,10 +78,28 @@ def write_local_playlist(playlist_path: str, tracks: List[str]) -> bool:
         bool: True if successful, False otherwise.
     """
     try:
-        with open(playlist_path, 'w', encoding="utf-8") as file:
-            file.write("#EXTM3U\n")
-            for track in tracks:
-                file.write(f"{track}\n")
+        desired_lines = ["#EXTM3U\n"] + [f"{track}\n" for track in tracks]
+        desired_content = "".join(desired_lines)
+
+        # Avoid rewriting identical content to prevent watcher feedback loops.
+        if os.path.exists(playlist_path):
+            try:
+                with open(playlist_path, 'r', encoding="utf-8") as existing_file:
+                    existing_content = existing_file.read()
+                if existing_content == desired_content:
+                    logger.debug(f"Playlist unchanged; skipping write: {playlist_path}")
+                    return True
+            except Exception as e:
+                # If read fails, fall back to rewriting.
+                logger.debug(f"Failed to read existing playlist for comparison ({playlist_path}): {e}")
+
+        # Write via temp file then replace for safer updates.
+        os.makedirs(os.path.dirname(os.path.abspath(playlist_path)), exist_ok=True)
+        tmp_path = f"{playlist_path}.tmp"
+        with open(tmp_path, 'w', encoding="utf-8") as file:
+            file.write(desired_content)
+        os.replace(tmp_path, playlist_path)
+
         logger.info(f"Written {len(tracks)} songs to the playlist: {playlist_path}")
         return True
     except Exception as e:

app/utils/plex_client.py

@@ -79,9 +79,7 @@ class PlexClient:
             # Update the base URL and connection status
             self.base_url = build_plex_url(scheme, url, port)
             self.connected = True
-            logger.info(
-                f"Connected to Plex server at {self.base_url} with token: {self.token}"
-            )
+            logger.info(f"Connected to Plex server at {self.base_url}.")
             return self.server, self.token
         except Exception as e:
             logger.warning(f"Failed to connect to Plex server: {str(e)}")
@@ -106,9 +104,7 @@ class PlexClient:
         self.token = account.authenticationToken
 
         self.server = PlexServer(self.base_url, self.token, timeout=timeout)
-        logger.debug(
-            f"Connected to Plex server with username: {username}, token: {self.token}"
-        )
+        logger.debug(f"Connected to Plex server with username: {username}.")
         return self.server, self.token
 
     def _connect_with_token(
@@ -124,7 +120,7 @@ class PlexClient:
         self.base_url = build_plex_url(scheme, url, port)
 
         self.server = PlexServer(self.base_url, token, timeout=timeout)
-        logger.debug(f"Connected to Plex server with token: {token}")
+        logger.debug("Connected to Plex server with token.")
         return self.server, token
 
     def _connect_check(self):

app/utils/sync_manager.py

@@ -2,6 +2,9 @@ import threading
 import asyncio
 import json
 import os
+import hashlib
+import re
+import time
 from datetime import datetime
 from app.utils.logger import logger
 from app.utils.playlist_merge import sync_all_playlists, SyncMode
@@ -19,6 +22,23 @@ class SyncManager:
         self._last_error = None
         self._listeners = [] # List of asyncio.Queue
         self._loop = None
+        # Suppress watcher events briefly after we write/delete local playlists.
+        # This prevents feedback loops where a sync triggers another sync.
+        self._watcher_suppress_until = 0.0
+
+        # Tunable defaults (seconds). Keep short to avoid missing real user edits.
+        self._watcher_suppress_after_write_seconds = 2.5
+        self._watcher_suppress_after_sync_seconds = 2.5
+
+    def suppress_watcher_events(self, seconds: float):
+        now = time.monotonic()
+        with self._lock:
+            self._watcher_suppress_until = max(self._watcher_suppress_until, now + float(seconds))
+
+    @property
+    def is_watcher_suppressed(self) -> bool:
+        with self._lock:
+            return time.monotonic() < self._watcher_suppress_until
 
     def set_event_loop(self, loop):
         self._loop = loop
@@ -76,6 +96,11 @@ class SyncManager:
             self._is_syncing = True
             self._last_status = "syncing"
             self._last_error = None
+            # Preemptively suppress watcher in case the poller notices changes right after.
+            self._watcher_suppress_until = max(
+                self._watcher_suppress_until,
+                time.monotonic() + self._watcher_suppress_after_sync_seconds,
+            )
         
         self._notify_listeners()
         logger.info(f"Starting sync (Source: {trigger_source})...")
@@ -139,9 +164,10 @@ class SyncManager:
                     local_result_path = os.path.join(output_dir, "outputs", "local_result.m3u8")
                     if os.path.exists(local_result_path):
                         tracks = load_local_playlist(local_result_path)
-                        dest_path = os.path.join(server_config.local_path, f"{playlist_name}.m3u8")
+                        dest_path = self._safe_local_playlist_path(server_config.local_path, playlist_name, ".m3u8")
                         # Ensure directory exists
                         os.makedirs(os.path.dirname(dest_path), exist_ok=True)
+                        self.suppress_watcher_events(self._watcher_suppress_after_write_seconds)
                         write_local_playlist(dest_path, tracks)
                     
                     # 2. Write Remote (Plex)
@@ -156,10 +182,12 @@ class SyncManager:
 
                 elif action == "deleted":
                     # Delete Local
-                    dest_path = os.path.join(server_config.local_path, f"{playlist_name}.m3u8")
+                    dest_path = self._safe_local_playlist_path(server_config.local_path, playlist_name, ".m3u8")
+                    self.suppress_watcher_events(self._watcher_suppress_after_write_seconds)
                     delete_local_playlist(dest_path)
                     # Also check for .m3u
-                    dest_path_m3u = os.path.join(server_config.local_path, f"{playlist_name}.m3u")
+                    dest_path_m3u = self._safe_local_playlist_path(server_config.local_path, playlist_name, ".m3u")
+                    self.suppress_watcher_events(self._watcher_suppress_after_write_seconds)
                     delete_local_playlist(dest_path_m3u)
                     
                     # Delete Remote
@@ -167,8 +195,63 @@ class SyncManager:
             except Exception as e:
                 logger.error(f"Error applying sync result for playlist {playlist_name}: {e}")
 
+    @staticmethod
+    def _safe_local_playlist_path(local_dir: str, playlist_name: str, extension: str) -> str:
+        base_dir = os.path.abspath(local_dir or "")
+        if not base_dir:
+            raise ValueError("Local playlist directory is not configured")
+
+        original = (playlist_name or "").strip()
+        # Drop any path components.
+        name = os.path.basename(original)
+        # Remove control chars.
+        name = re.sub(r"[\x00-\x1f\x7f]", "_", name)
+        # Replace path separators and Windows-invalid characters.
+        invalid = set('<>:"/\\|?*')
+        cleaned = "".join(("_" if ch in invalid else ch) for ch in name).strip().strip(". ")
+
+        windows_reserved = {
+            "CON", "PRN", "AUX", "NUL",
+            *(f"COM{i}" for i in range(1, 10)),
+            *(f"LPT{i}" for i in range(1, 10)),
+        }
+
+        needs_hash = False
+        if not cleaned:
+            cleaned = "playlist"
+            needs_hash = True
+        if cleaned.upper() in windows_reserved:
+            needs_hash = True
+        if cleaned != original:
+            needs_hash = True
+
+        cleaned = cleaned[:160].rstrip().strip(". ")
+        if not cleaned:
+            cleaned = "playlist"
+            needs_hash = True
+
+        if needs_hash:
+            digest = hashlib.sha1(original.encode("utf-8", errors="ignore")).hexdigest()[:8]
+            cleaned = f"{cleaned}__{digest}"
+
+        filename = f"{cleaned}{extension}"
+        candidate = os.path.abspath(os.path.join(base_dir, filename))
+
+        # Ensure the final path stays within base_dir.
+        if os.path.commonpath([base_dir, candidate]) != base_dir:
+            raise ValueError("Refusing to write outside local playlist directory")
+
+        return candidate
+
     def _complete_sync(self, status, error=None):
+        now = time.monotonic()
         with self._lock:
+            # Keep watcher suppression a bit after sync finishes, since PollingObserver
+            # may detect file changes on the next polling tick.
+            self._watcher_suppress_until = max(
+                self._watcher_suppress_until,
+                now + self._watcher_suppress_after_sync_seconds,
+            )
             self._last_status = status
             self._last_error = error
             self._last_sync_time = datetime.now()

app/utils/watcher.py

@@ -21,6 +21,11 @@ class PlaylistEventHandler(FileSystemEventHandler):
 
         if event.is_directory:
             return
+
+        # For moved events, the interesting path is the destination.
+        event_path = getattr(event, "dest_path", None) if event.event_type == "moved" else event.src_path
+        if not event_path:
+            return
         
         # Filter out noisy events. Only listen to actual changes.
         # 'opened' and 'closed' (without write) are read events and should be ignored.
@@ -28,16 +33,25 @@ class PlaylistEventHandler(FileSystemEventHandler):
             return
 
         # Ignore temporary files or hidden files
-        filename = os.path.basename(event.src_path)
+        filename = os.path.basename(event_path)
         if filename.startswith('.'):
             return
 
+        # Only watch playlist files to avoid noisy triggers.
+        if not filename.lower().endswith((".m3u", ".m3u8")):
+            return
+
         # Prevent feedback loops: if sync is in progress, ignore events
         if sync_manager.is_syncing:
-            logger.debug(f"[Watcher] Ignoring event {event.event_type} on {event.src_path} because sync is in progress.")
+            logger.debug(f"[Watcher] Ignoring event {event.event_type} on {event_path} because sync is in progress.")
             return
 
-        logger.info(f"[Watcher] Accepted file change: {event.event_type} {event.src_path}")
+        # Prevent feedback loops: ignore events right after sync writes/deletes.
+        if getattr(sync_manager, "is_watcher_suppressed", False):
+            logger.debug(f"[Watcher] Ignoring event {event.event_type} on {event_path} because watcher is suppressed.")
+            return
+
+        logger.info(f"[Watcher] Accepted file change: {event.event_type} {event_path}")
         self.trigger_sync()
 
     def trigger_sync(self):