Python Watchdog: trigger a function only when there are no more changes for a certain period

watchdog_with_timer.py

#!/usr/bin/python3
#
# Purpose:
#   Use watchdog to monitor a directory. After a certain amount of time without any change
#   the processing is triggered.
#

import os.path
import time
import threading

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

DIR=os.path.dirname(__file__)
WATCHED_DIR=os.path.join(DIR, 'my-dir')
# These are seconds
WAIT_TIME=5


class DebounceHandler(FileSystemEventHandler):
    def __init__(self, func, wait_time):
        self.func = func
        self.wait_time = wait_time
        self.timer = None

    def on_any_event(self, event):
        if self.timer:
            self.timer.cancel()
        self.timer = threading.Timer(self.wait_time, self.func)
        self.timer.start()

def process_changes():
    print("No more changes detected. Processing changes now.")

if __name__ == "__main__":
    event_handler = DebounceHandler(process_changes, WAIT_TIME)
    observer = Observer()
    observer.schedule(event_handler, path=WATCHED_DIR, recursive=True)
    observer.start()

    print(f"Starting observer for {WATCHED_DIR!r}...")

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

    print("Done.")