Can I create a filesystem object of a specific directory?

Question

Need to create this type of object (from kivy.properties & Kivy filechooser)

ObjectProperty(FileSystemLocal(), baseclass=FileSystemAbstract)

Answer 1

The FileSystemLocal class is a simple interface to some os and os.path methods. For example, the listdir() method of FileSystemLocal is simply a call to os.listdir() . So it is not specific to any directory, it is just specific to the local os and os.path . So, technically, the answer is no.

Perhaps you could define your own FileSystemLocal subclass that meets your requirements.

Here is an example of an extension of FileSystemLocal that uses a specific directory:

from os import listdir
from os.path import (basename, join, getsize, isdir)

from sys import platform as core_platform

from kivy import Logger
from kivy.uix.filechooser import FileSystemAbstract, _have_win32file

platform = core_platform

_have_win32file = False
if platform == 'win':
    # Import that module here as it's not available on non-windows machines.
    try:
        from win32file import FILE_ATTRIBUTE_HIDDEN, GetFileAttributesExW, \
                              error
        _have_win32file = True
    except ImportError:
        Logger.error('filechooser: win32file module is missing')
        Logger.error('filechooser: we cant check if a file is hidden or not')


class FileSystemLocalDir(FileSystemAbstract):
    def __init__(self, **kwargs):
        self.dir = kwargs.pop('dir', None)
        super(FileSystemLocalDir, self).__init__()

    def listdir(self, fn):
        if self.dir is not None:
            fn = join(self.dir, fn)
        print('listdir for', fn)
        return listdir(fn)

    def getsize(self, fn):
        if self.dir is not None:
            fn = join(self.dir, fn)
        return getsize(fn)

    def is_hidden(self, fn):
        if self.dir is not None:
            fn = join(self.dir, fn)
        if platform == 'win':
            if not _have_win32file:
                return False
            try:
                return GetFileAttributesExW(fn)[0] & FILE_ATTRIBUTE_HIDDEN
            except error:
                # This error can occurred when a file is already accessed by
                # someone else. So don't return to True, because we have lot
                # of chances to not being able to do anything with it.
                Logger.exception('unable to access to <%s>' % fn)
                return True

        return basename(fn).startswith('.')

    def is_dir(self, fn):
        if self.dir is not None:
            fn = join(self.dir, fn)
        return isdir(fn)

This can be used as:

fsld = FileSystemLocalDir(dir='/home')
print('dir:', fsld.dir)
print('listdir .:', fsld.listdir('.'))
print('listdir freddy:', fsld.listdir('freddy'))  # lists home directory of user `freddy`
print('listdir /usr:', fsld.listdir('/usr')) # this will list /usr regardless of the setting for self.dir

Note:

• The FileSystemLocalDir is based heavily on FileSystemLocal .
• The dir= in the constructor sets the default directory that is consulted for all the methods of FileSystemLocalDir .
• If the dir= argument is not provided, the FileSystemLocalDir is equivalent to FileSystemLocal .
• If an argument to any method of FileSystemLocalDir begins with a / , it is treated as an absolute path and the provided default directory is ignored (this is an effect of the use of os.join ).