How would I use Watchdog to get triggered when DVD is inserted?

[Daring_T]

I am making a DVD ripping script and I am trying to use the Watchdog Lib to trigger my main function. The problem is, I'm getting this error:

Error:
PermissionError: [WinError 21] The device is not ready.

Is there a way for Watchdog to wait till it's loaded?

This is my test code if that helps anyone and if anyone has any questions feel free to ask.

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from watchdog.observers import Observer from watchdog.events import FileSystemEventHandler   event_handler = FileSystemEventHandler()   # calling test functions event_handler.on_created = lambda : print("created") event_handler.on_deleted = lambda : print("deleted") event_handler.on_modified = lambda : print("modified") event_handler.on_moved = lambda : print("moved")       path = "D://" observer = Observer() observer.schedule(event_handler, path, recursive=True) observer.start() try:     print("Monitoring")     while True:         time.sleep(1) except KeyboardInterrupt:     observer.stop()     print("Terminating") observer.join()

[jefsummers]

Is that the complete error message? No line number or traceback?

[Daring_T]

This happens when a DVD is not inserted and I want Watchdog to wait until a DVD is inserted then run my main function.
This is the complete traceback error:

Error:
Traceback (most recent call last):
  File "C:/Users/Daren/Documents/01 PYTHON/DVD Auto Ripper/watcher.py", line 16, in <module>
    observer.start()
  File "C:\Users\Daren\Documents\01 PYTHON\DVD Auto Ripper\venv\lib\site-packages\watchdog\observers\api.py", line 256, in start
    emitter.start()
  File "C:\Users\Daren\Documents\01 PYTHON\DVD Auto Ripper\venv\lib\site-packages\watchdog\utils\__init__.py", line 93, in start
    self.on_thread_start()
  File "C:\Users\Daren\Documents\01 PYTHON\DVD Auto Ripper\venv\lib\site-packages\watchdog\observers\read_directory_changes.py", line 67, in on_thread_start
    self._handle = get_directory_handle(self.watch.path)
  File "C:\Users\Daren\Documents\01 PYTHON\DVD Auto Ripper\venv\lib\site-packages\watchdog\observers\winapi.py", line 316, in get_directory_handle
    return CreateFileW(path, FILE_LIST_DIRECTORY, WATCHDOG_FILE_SHARE_FLAGS,
  File "C:\Users\Daren\Documents\01 PYTHON\DVD Auto Ripper\venv\lib\site-packages\watchdog\observers\winapi.py", line 112, in _errcheck_handle
    raise ctypes.WinError()
PermissionError: [WinError 21] The device is not ready.

[jefsummers]

Looks like the error starts in line 45 which is not supplied.

[Daring_T]

Looks like the error starts in line 45 which is not supplied.

I just fixed my traceback error. The traceback should now line up with the test script.

[jefsummers]

Have you tried using a try..except block around line 15 (observer.start())?

[Daring_T]

I have tried using a try except block but still get the same error. I have even tried putting a 10 sec sleep time but it don’t help.

[jefsummers]

This is how I would do the try except

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failed = True while failed:     try:         observer.start()         failed = False     except:         wait(5)

Is that what you tried? Should not have seen that error message, I would think

[deanhystad]

Is the DVD going to show up as D: or does it show up in D:? If it shows up as D: I don't think you can use watchdog to see when a DVD is installed. Sure, you can keep trying to start the observer and it will fail until a DVD is installed, but you get the same info trying to read the D:\\ folder.

In a windows program you would use the RegisterDeviceNotification call. I don't know of any python wrapper library for this system call.

[Daring_T]

This is how I would do the try except

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failed = True while failed:     try:         observer.start()         failed = False     except:         wait(5)

Is that what you tried? Should not have seen that error message, I would think

It does work the way you wrote it and I don't what I messed up, but the thing is, I could have used the os library, while loop, and the time.sleep function to do the same thing. I wanted to use the Watchdog lib. to be more efficient with my script, but it looks like I am going beyond what this library can do.