Fix file watchers

plugins/contents/fps_contents/__init__.py

@@ -1,3 +1 @@
-from .fileid import get_watch  # noqa
-
 __version__ = "0.0.44"

plugins/contents/fps_contents/fileid.py

@@ -1,6 +1,6 @@
 import asyncio
 import logging
-from typing import Callable, Dict, List, Optional
+from typing import Dict, List, Optional
 from uuid import uuid4
 
 import aiosqlite
@@ -151,10 +151,13 @@ async def watch_files(self):
     def watch(self, path: str) -> Watcher:
         watcher = Watcher(path)
         if path not in self.watchers:
-            self.watchers[path] = watchers = []  # type: ignore
-        watchers.append(watcher)
+            self.watchers[path] = []
+        self.watchers[path].append(watcher)
         return watcher
 
+    def unwatch(self, path: str, watcher: Watcher):
+        self.watchers[path].remove(watcher)
+
 
 async def get_mtime(path, db) -> Optional[float]:
     if db:
@@ -192,7 +195,3 @@ async def maybe_rename(
             other_paths.remove(other_path)
             return
     changed_paths.append(changed_path)
-
-
-def get_watch() -> Callable[[str], Watcher]:
-    return FileIdManager().watch

plugins/yjs/fps_yjs/routes.py

@@ -18,13 +18,6 @@
 from fps_contents.fileid import FileIdManager
 from fps_contents.routes import read_content, write_content  # type: ignore
 
-try:
-    from fps_contents import get_watch
-
-    has_watch = True
-except ImportError:
-    has_watch = False
-
 from fps_auth_base import websocket_auth  # type: ignore
 from jupyter_ydoc import ydocs as YDOCS  # type: ignore
 from ypy_websocket.websocket_server import WebsocketServer, YRoom  # type: ignore
@@ -237,24 +230,16 @@ async def on_message(self, message: bytes) -> bool:
         return skip
 
     async def watch_file(self):
-        if has_watch:
-            file_format, file_type, file_path = await self.get_file_info()
-            while True:
-                async for changes in get_watch()(file_path):
-                    file_format, file_type, new_file_path = await self.get_file_info()
-                    if new_file_path != file_path:
-                        # file was renamed
-                        file_path = new_file_path
-                        break
-                    await self.maybe_load_document()
-        else:
-            # contents plugin doesn't provide watcher, fall back to polling
-            poll_interval = 1  # FIXME: pass in config
-            if not poll_interval:
-                self.room.watcher = None
-                return
-            while True:
-                await asyncio.sleep(poll_interval)
+        file_format, file_type, file_path = await self.get_file_info()
+        while True:
+            watcher = FileIdManager().watch(file_path)
+            async for changes in watcher:
+                file_format, file_type, new_file_path = await self.get_file_info()
+                if new_file_path != file_path:
+                    # file was renamed
+                    FileIdManager().unwatch(file_path, watcher)
+                    file_path = new_file_path
+                    break
                 await self.maybe_load_document()
 
     async def maybe_load_document(self):