Bind9 Zone Directory Watcher

watcher.py

import time
import os
import subprocess
import re
from watchdog.observers import Observer
from watchdog.events import FileSystemEventHandler

def outputCmd(cmd):
    proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    stdout,stderr = proc.communicate()
    if stderr != None:
        return stderr.decode('utf-8')
    return stdout.decode('utf-8')

def outputLog(text):
    logFile = '/var/log/watcher.log'
    with open(logFile, 'a+') as f:
        f.write(text)

class Watcher:
    DIRECTORY_TO_WATCH = "/var/named/zones"

    def __init__(self):
        self.observer = Observer()

    def run(self):
        event_handler = Handler()
        self.observer.schedule(event_handler, self.DIRECTORY_TO_WATCH, recursive=True)
        self.observer.start()
        try:
            while True:
                time.sleep(5)
        except:
            self.observer.stop()
            print ("Error")

        self.observer.join()

class Handler(FileSystemEventHandler):
    @staticmethod
    def on_any_event(event):
        domain = os.path.basename(event.src_path).replace('.zone', '')

        if event.is_directory:
            return None
        
        elif not re.match('^[a-zA-Z\d-]{,63}(\.[a-zA-Z\d-]{,5})$', domain):
            return None 

        elif event.event_type == 'created':
            outputLog('Created => ' + domain +'\n'+ outputCmd(['rndc', 'reconfig', ' ' + domain]))

        elif event.event_type == 'deleted':
            outputLog('Deleted => ' + domain +'\n'+ outputCmd(['rndc', 'delzone', ' ' + domain]))

if __name__ == '__main__':
    w = Watcher()
    w.run()