Files
superset2/superset/extensions/local_extensions_watcher.py
2025-09-23 10:24:23 -07:00

134 lines
4.4 KiB
Python

# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
"""Local extensions file watcher for development mode."""
from __future__ import annotations
import logging
import os
import threading
import time
from pathlib import Path
from typing import Any, TYPE_CHECKING
from flask import Flask
if TYPE_CHECKING:
pass
logger = logging.getLogger(__name__)
def _get_file_handler_class() -> Any:
"""Get the file handler class, importing watchdog only when needed."""
try:
from watchdog.events import FileSystemEventHandler
class LocalExtensionFileHandler(FileSystemEventHandler):
"""Custom file system event handler for LOCAL_EXTENSIONS directories."""
def on_any_event(self, event: Any) -> None:
"""Handle any file system event in the watched directories."""
if event.is_directory:
return
logger.info(
"File change detected in LOCAL_EXTENSIONS: %s", event.src_path
)
# Touch superset/__init__.py to trigger Flask's file watcher
superset_init = Path("superset/__init__.py")
logger.info("Triggering restart by touching %s", superset_init)
os.utime(superset_init, (time.time(), time.time()))
return LocalExtensionFileHandler
except ImportError:
logger.warning("watchdog not installed, LOCAL_EXTENSIONS watcher disabled")
return None
def setup_local_extensions_watcher(app: Flask) -> None: # noqa: C901
"""Set up file watcher for LOCAL_EXTENSIONS directories."""
# Only set up watcher in debug mode or when Flask reloader is enabled
if not (app.debug or app.config.get("FLASK_USE_RELOAD", False)):
return
# Check if we're running under Flask's reloader to avoid conflicts
if os.environ.get("WERKZEUG_RUN_MAIN") == "true":
return
local_extensions = app.config.get("LOCAL_EXTENSIONS", [])
if not local_extensions:
return
# Try to import watchdog and get handler class
handler_class = _get_file_handler_class()
if not handler_class:
return
# Collect dist directories to watch
watch_dirs = []
for ext_path in local_extensions:
if not ext_path:
continue
ext_path = Path(ext_path).resolve()
if not ext_path.exists():
logger.warning("LOCAL_EXTENSIONS path does not exist: %s", ext_path)
continue
dist_path = ext_path / "dist"
watch_dirs.append(str(dist_path))
logger.info("Watching LOCAL_EXTENSIONS dist directory: %s", dist_path)
if not watch_dirs:
return
try:
from watchdog.observers import Observer
# Set up and start the file watcher
event_handler = handler_class()
observer = Observer()
for watch_dir in watch_dirs:
try:
observer.schedule(event_handler, watch_dir, recursive=True)
except Exception as e:
logger.warning("Failed to watch directory %s: %s", watch_dir, e)
continue
observer.daemon = True
observer.start()
logger.info(
"LOCAL_EXTENSIONS file watcher started for %s directories", # noqa: E501
len(watch_dirs),
)
except Exception as e:
logger.error("Failed to start LOCAL_EXTENSIONS file watcher: %s", e)
def start_local_extensions_watcher_thread(app: Flask) -> None:
"""Start the LOCAL_EXTENSIONS file watcher in a daemon thread."""
# Start setup in daemon thread if we're in main thread
if threading.current_thread() is threading.main_thread():
threading.Thread(
target=lambda: setup_local_extensions_watcher(app), daemon=True
).start()