Finding empty directories in Python

Question

All,

What is the best way to check to see if there is data in a directory before deleting it? I am browsing through a couple pages to find some pics using wget and of course every page does not have an image on it but the directory is still created.

dir = 'Files\\%s' % (directory)
os.mkdir(dir)
cmd = 'wget -r -l1 -nd -np -A.jpg,.png,.gif -P %s %s' %(dir,  i[1])
os.system(cmd)
if not os.path.isdir(dir):
    os.rmdir(dir)

I would like to test to see if a file was dropped in the directory after it was created. If nothing is there...delete it.

Thanks, Adam

Dongdonga

Define "empty". What if there are subdirectories? Should they be checked for data? Should they also be deleted if there is no data in them? – Imperception

I don't have any subdirectories in this case just a single folder that may or may not have pics in it. – Dongdonga

Please do not use os.system to call wget. Use subprocess.Popen – Sporozoite

In essence: isempty = lambda path : not next(os.scandir(path), None) – Willson

Don't use os.listdir or try, except statements. os.scandir is orders of magnitude faster. – Willson

Answer 1

import os

if not os.listdir(dir):
    os.rmdir(dir)

LBYL style.
for EAFP, see mouad's answer.

Kaslik

If the directory contains thousands of files, would os.listdir(dir) return size be a issue? @Corey Goldberg – Phyfe

Answer 2

I will go with EAFP like so:

try:
    os.rmdir(dir)
except OSError as ex:
    if ex.errno == errno.ENOTEMPTY:
        print "directory not empty"

os.rmdir will not delete a directory that is not empty.

Agripinaagrippa

+1: Simple. Direct. And it delegates all the tricky decision-making to the OS where it belongs. – Manifold

Note that this function silently drops all other errors (such as EACCESS), which you may want to report. Note that fixing that naively would probably result in reporting errors for non-empty directories, which you probably want to ignore. Not as simple as it seems :-) – Lonnielonny

How about else: raise? – Lowly

nice but: NameError: name 'errno' is not defined you need import errno! – Ambroid

Answer 3

Try:

if not os.listdir(dir): 
    print "Empty"

or

if os.listdir(dir) == []:
    print "Empty"

Fanjet

Answer 4

This can now be done more efficiently in Python3.5+, since there is no need to build a list of the directory contents just to see if its empty:

import os

def is_dir_empty(path):
    with os.scandir(path) as scan:
        return next(scan, None) is None

Example usage:

if os.path.isdir(directory) and is_dir_empty(directory):
    os.rmdir(directory)

Acetone

Answer 5

What if you did checked if the directory exists, and whether there is content in the directory... something like:

if os.path.isdir(dir) and len(os.listdir(dir)) == 0:
    os.rmdir(dir)

Frigorific

Answer 6

If the empty directories are already created, you can place this script in your outer directory and run it:

import os

def _visit(arg, dirname, names):
    if not names:
        print 'Remove %s' % dirname
        os.rmdir(dirname)

def run(outer_dir):
    os.path.walk(outer_dir, _visit, 0)

if __name__ == '__main__':
    outer_dir = os.path.dirname(__file__)
    run(outer_dir)
    os.system('pause')

Ravioli

Answer 7

Here is the fastest and optimized way to check if the directory is empty or not.

empty = False
for dirpath, dirnames, files in os.walk(dir):
    if files:
        print("Not empty !") ;
    if not files:
        print("It is empty !" )
        empty = True
    break ;

---

The other answers mentioned here are not fast because , if you want use the usual os.listdir() , if the directory has too many files , it will slow ur code and if you use the os.rmdir( ) method to try to catch the error , then it will simply delete that folder. This might not be something which u wanna do if you just want to check for emptyness .

Pollack

Using os.scandir is fast, with the advantage of being clearer and not needing to generate lists that aren't use. – Acetone

Answer 8

I have follews Bash checking if folder has contents answer.

Mainly it is similiar approach as @ideasman42's answer on https://mcmap.net/q/369488/-finding-empty-directories-in-python, in order to not to build the complete list, which would probably work on Debian as well.

there is no need to build a list of the directory contents just to see if its empty:

---

os.walk('.') returns the complete files under a directory and if there thousands it may be inefficient. Instead following command find "$target" -mindepth 1 -print -quit returns first found file and quits. If it returns an empty string, which means folder is empty.

You can check if a directory is empty using find, and processing its output

def is_dir_empty(absolute_path):
    cmd = ["find", absolute_path, "-mindepth", "1", "-print", "-quit"]
    output = subprocess.check_output(cmd).decode("utf-8").strip()
    return not output

print is_dir_empty("some/path/here")

Phyfe