Watchdog on windows with python3.4

Question

I am trying to learn to use watchdog utility on windows.

I have gone through basic examples available on google. I am trying to write a script which will monitor a given directory and then will send mail if any sub-directory is created which has a file named version.

import time
from watchdog.observers import Observer
from watchdog.events import DirCreatedEvent
import re
import smtplib




class MyHandler(DirCreatedEvent):

    def process(self,event):


        fileTocheck = "Version"

        with open(event.src_path+"\\"+fileTocheck) as version:
            chngstring = version.read()
            changeNumber = re.findall(r"\D(\d{5})\D",chngstring)
            if not changeNumber:
                return


        server = smtplib.SMTP('smtp.gmail.com',587)
        server.login("xyz@gmail.com","abc@123")
        message = "New Build has been create with Chnage Number %d"  %int(changeNumber[0])
        server.sendmail("xyz@gmail.com","abc@gmail.com",message)

    def on_created(self,event):
        self.process(event)



if __name__ == '__main__':
    observer = Observer()
    path = "D:\\"
    observer.schedule(MyHandler(),path,recursive=True)
    observer.start()

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

    observer.join()

The problem is that whenever I am running the script I am getting this error:

>>> ================================ RESTART   ================================
>>> 
Traceback (most recent call last):
File "C:/Users/Prince/Desktop/KeepLearing/Watchdog.py", line 37, in <module>
observer.schedule(MyHandler(),path,path,recursive=True)
TypeError: __init__() missing 1 required positional argument: 'src_path'

I am providing proper path while envoking observer.schedule, I don't understand why I am getting this.

Please help me find out what I am missing.

Answer 1

The error is here:

class MyHandler(DirCreatedEvent):

You've made your handler a subclass of DirCreatedEvent. The error is arising because DirCreatedEvent's __init__ method, which you are not overriding in your MyHandler class, has one parameter, named src_path, and when you create a handler using MyHandler(), you're not passing in any value for this parameter.

It would be more correct to say your handler handles events than to say your handler is an event. So instead of subclassing DirCreatedEvent, you need to subclass an event handler, and FileSystemEventHandler seems to be the one you want.

So, change the above line to

class MyHandler(FileSystemEventHandler):

Also, import the FileSystemEventHandler class from watchdog.events.

Note that your MyHandler class will receive events for file creation as well as for directory creation. The easiest way to ignore them is to modify your on_created method to:

    def on_created(self,event):
        if isinstance(event, DirCreatedEvent):
            self.process(event)