How to run the RegexMatchingEventHandler of Watchdog correctly?

Question

I'm working on a small tool for a GameApi. This Api works with .log-files. They are provided in a specific location. I want to observe this location with with watchdog and it is working fine, if I use the PatternMatchingEventHandler. But if I use the RegexMatchingEventHandler it fails. I want to use Regex because there a many .log-files and I only want to check the files from today.

Extension: I use Watchdog with the functions:

on_created
on_deleted
on_moved
on_modified

This Website shows the code I am using: https://www.thepythoncorner.com/2019/01/how-to-create-a-watchdog-in-python-to-look-for-filesystem-changes/

I tested my Regex function normaly with re. This is doing absolutly fine. But even if I try the Regex Entry: ['\w+.log'] it did not work.

I provide you my Regex to understand what I want to do:

regexes = ["^Journal\.190901\d{6}\.\d{2}\.log$"]

I expected a message everytime I change one of my .log-files but this is only happend i f i use the PatternMatchingEventHAndle

EDIT: Now I present you you my minimal Example:

import time
from watchdog.observers import Observer
from watchdog.events import RegexMatchingEventHandler

if __name__ == "__main__":
    regexes = ["^Journal\.190901\d{6}\.\d{2}\.log$"]
    ignore_regexes= []
    ignore_directories = False
    case_sensitive = True
    my_event_handler = RegexMatchingEventHandler(regexes,ignore_regexes,ignore_directories,case_sensitive)

    def on_modified(event):
        print(f"hey buddy, {event.src_path} has been modified")

    my_event_handler.on_modified = on_modified

# Observer
    path = "."
    go_recursively = True
    my_observer = Observer()
    my_observer.schedule(my_event_handler, path, recursive=go_recursively)

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

Answer 1

This is just about the pattern of the path returned by the event handler, it begins by the path to the root of the folder specified in path (path = "." in your example) .

• It can help to inspect any patterns of the paths returned, and check what you need exactly:

  regexes = ['.+']  # will match everything 
  

• To track files in the current directory with path = ".":

  # linux (example path : ./Journal[...].log)
  regexes = ['^\./Journal\.190901\d{6}\.\d{2}\.log$']
  
  # windows (example path : .\Journal[...].log)
  regexes = ["^\.\\\\Journal\.190901\d{6}\.\d{2}\.log$"]
  
  # both
  regexes = ["^\.(/|\\\\)Journal\.190901\d{6}\.\d{2}\.log$"]
  

• if you define a subfolder named logs and you specify the root like path = "logs"

  # (example path : logs/Journal[...].log or logs\Journal[...].log
  regexes = ['^logs(/|\\\\)logs/Journal\.190901\d{6}\.\d{2}\.log$']