Watch - A simple script to watch for changes in a python file and run it.

watch.py

import argparse
import subprocess
import time

from watchdog.events import FileSystemEventHandler
from watchdog.observers import Observer

'''
Watch - A simple script to watch for changes in a python file and run it.
Usage: python watch.py [script_file]
if you don't specify a script_file, it will default to app.py
It requires watchdog to be installed
pip install watchdog
'''
class FileChangeHandler(FileSystemEventHandler):
    def __init__(self, script_file):
        self.script_file = script_file

    def on_modified(self, event):
        if not event.is_directory and event.src_path.endswith('.py'):
            print(f"Changes detected in {event.src_path}")
            subprocess.run(["python", self.script_file])


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("script_file", nargs='?', default="app.py", help="Python script file to watch")
    args = parser.parse_args()

    event_handler = FileChangeHandler(args.script_file)
    observer = Observer()
    observer.schedule(event_handler, path='.', recursive=True)
    observer.start()

    try:
        while True:
            time.sleep(1)
    except KeyboardInterrupt:
        observer.stop()

    observer.join()