Watchdog Library In Python On Os X -- Not Showing Full Event Path

I just started working with the Watchdog library in Python on Mac, and am doing some basic tests to make sure things are working like I would expect. Unfortunately, they're not --

Solution 1:

Problem solved. As it turns out, FSEvents in OS X returns only the directory for file modified events, leaving you to scan the directory yourself to find out which file was modified. This is not mentioned in Watchdog documentation, though it's found easily in FSEvents documentation.

To get the full path to the file, I added the following snippet of code (inspired by this StackOverflow thread) to find the most recently modified file in a directory, to be used whenever event.src_path returns a directory.

if(event.is_directory):
    files_in_dir = [event.src_path+"/"+f for f inos.listdir(event.src_path)]
    mod_file_path = max(files_in_dir, key=os.path.getmtime)

mod_file_path contains the full path to the modified file.

Solution 2:

Thanks ekl for providing your solution. I just stumbled across the same problem. However, I used to use PatternMatchingEventHandler, which requires small changes to your solution:

• subclass from FileSystemEventHandler
• create an attribute pattern where you store your pattern matching. This is not as flexible as the original PatternMatchingEventHandler, but should suffice most needs, and you will get the idea anyway if you want to extend it.

Here's the code you have to put in your FileSystemEventHandlersubclass:

def __init__(self, pattern='*'):
    super(MidiEventHandler, self).__init__()
    self.pattern = pattern


def on_modified(self, event):
    super(MidiEventHandler, self).on_modified(event)

    if event.is_directory:
        files_in_dir = [event.src_path+"/"+f for f inos.listdir(event.src_path)]
        iflen(files_in_dir) > 0:
            modifiedFilename = max(files_in_dir, key=os.path.getmtime)
        else:
            returnelse:
        modifiedFilename = event.src_path

    if fnmatch.fnmatch(os.path.basename(modifiedFilename), self.pattern):
        print"Modified MIDI file: %s" % modifiedFilename

One other thing I changed is that I check whether the directory is empty or not before running max() on the file list. max() does not work with empty lists.