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How do I check if directory exists in Python?

How do I check if a directory exists?

A word of warning - the highest rated answer might be susceptible to race conditions. You might want to perform os.stat instead, to see if the directory both exists and is a directory at the same moment.
@d33tah You may have a good point but I don't see a way to use os.stat to tell directory from a file. It raises OSError when the path is invalid, no matter whether it's file or directory. Also, any code after checking is also susceptible to race conditions.
@TomášZato: which leads to a conclusion that it's safed to just perform the operation and handle errors.
@David542 I added a clarification case with tests for precision for "isdir" "exists". I think you would learn anything now. But it could illuminate new people.
Maybe this answer helps with the usage of os.stat

M
Mateen Ulhaq

Use os.path.isdir for directories only:

>>> import os
>>> os.path.isdir('new_folder')
True

Use os.path.exists for both files and directories:

>>> import os
>>> os.path.exists(os.path.join(os.getcwd(), 'new_folder', 'file.txt'))
False

Alternatively, you can use pathlib:

 >>> from pathlib import Path
 >>> Path('new_folder').is_dir()
 True
 >>> (Path.cwd() / 'new_folder' / 'file.txt').exists()
 False

@syedrakib While parentheses can be used to indicate that an object is callable, that's not useful in Python, since even classes are callable. Also, functions are first-class values in Python, and you can use them without the parentheses notation, like in existing = filter(os.path.isdir(['/lib', '/usr/lib', '/usr/local/lib'])
You can pass functions to other functions, like map, but in the general case, you call functions with arguments and parentheses. Also, there is some typo in your example. presumably you mean filter(os.path.isdir, ['/lib', '/usr/lib', '/usr/local/lib']).
Also, there is os.path.isfile(path) if you only care about whether it is a file.
Be aware that on some platforms these will return false if the file/directory exists, but a read permission error also occurs.
The examples above are not portable, and would be better if rewritten using os.path.join, or the pathlib stuff recommended below. Something like this: print(os.path.isdir(os.path.join('home', 'el')))
j
joelostblom

Python 3.4 introduced the pathlib module into the standard library, which provides an object oriented approach to handle filesystem paths. The is_dir() and exists() methods of a Path object can be used to answer the question:

In [1]: from pathlib import Path

In [2]: p = Path('/usr')

In [3]: p.exists()
Out[3]: True

In [4]: p.is_dir()
Out[4]: True

Paths (and strings) can be joined together with the / operator:

In [5]: q = p / 'bin' / 'vim'

In [6]: q
Out[6]: PosixPath('/usr/bin/vim') 

In [7]: q.exists()
Out[7]: True

In [8]: q.is_dir()
Out[8]: False

Pathlib is also available on Python 2.7 via the pathlib2 module on PyPi.


Some explanation would be helpful. Why are you doing "p / 'bin' / 'vim' ?
@frank I elaborated a bit on the second part of the answer.
K
Kirk Strauser

So close! os.path.isdir returns True if you pass in the name of a directory that currently exists. If it doesn't exist or it's not a directory, then it returns False.


and if you want to create it os.path.isdir(path) or os.makedirs(path)
Or using pathlib: Path(path).mkdir(parents=True, exist_ok=True) creates a nested path in one operation.
a
aganders3

Yes, use os.path.exists().


That doesn't check that the path is a directory.
Good call. Others have pointed out that os.path.isdir will accomplish that.
If you understand that this doesn't answer the question, why don't you remove the answer?
@CamilStaps This question was viewed 354000 times (by now). Answers here are not only for OP, they are for anyone who could come here for whatever reason. aganders3's answer is pertinent even if it does not directly resolve OP's problem.
@Gabriel then it should be made clear in the answer what this actually does.
W
Wickkiey

We can check with 2 built in functions

os.path.isdir("directory")

It will give boolean true the specified directory is available.

os.path.exists("directoryorfile")

It will give boolead true if specified directory or file is available.

To check whether the path is directory;

os.path.isdir("directorypath")

will give boolean true if the path is directory


This is entirely redundant with the older, top answer.
R
RanRag
s
sksoumik

The following code checks the referred directory in your code exists or not, if it doesn't exist in your workplace then, it creates one:

import os

if not os.path.isdir("directory_name"):
    os.mkdir("directory_name")

A
AlG

As in:

In [3]: os.path.exists('/d/temp')
Out[3]: True

Probably toss in a os.path.isdir(...) to be sure.


T
Tyler A.

Just to provide the os.stat version (python 2):

import os, stat, errno
def CheckIsDir(directory):
  try:
    return stat.S_ISDIR(os.stat(directory).st_mode)
  except OSError, e:
    if e.errno == errno.ENOENT:
      return False
    raise

What is the advantage to use stat and errno instead of pathlib2? Is it the race conditions mentioned in d33tah's comment to the question?
N
Nathan

You may also want to create the directory if it's not there.

Source, if it's still there on SO.

=====================================================================

On Python ≥ 3.5, use pathlib.Path.mkdir:

from pathlib import Path
Path("/my/directory").mkdir(parents=True, exist_ok=True)

For older versions of Python, I see two answers with good qualities, each with a small flaw, so I will give my take on it:

Try os.path.exists, and consider os.makedirs for the creation.

import os
if not os.path.exists(directory):
    os.makedirs(directory)

As noted in comments and elsewhere, there's a race condition – if the directory is created between the os.path.exists and the os.makedirs calls, the os.makedirs will fail with an OSError. Unfortunately, blanket-catching OSError and continuing is not foolproof, as it will ignore a failure to create the directory due to other factors, such as insufficient permissions, full disk, etc.

One option would be to trap the OSError and examine the embedded error code (see Is there a cross-platform way of getting information from Python’s OSError):

import os, errno

try:
    os.makedirs(directory)
except OSError as e:
    if e.errno != errno.EEXIST:
        raise

Alternatively, there could be a second os.path.exists, but suppose another created the directory after the first check, then removed it before the second one – we could still be fooled.

Depending on the application, the danger of concurrent operations may be more or less than the danger posed by other factors such as file permissions. The developer would have to know more about the particular application being developed and its expected environment before choosing an implementation.

Modern versions of Python improve this code quite a bit, both by exposing FileExistsError (in 3.3+)...

try:
    os.makedirs("path/to/directory")
except FileExistsError:
    # directory already exists
    pass

...and by allowing a keyword argument to os.makedirs called exist_ok (in 3.2+).

os.makedirs("path/to/directory", exist_ok=True)  # succeeds even if directory exists.

E
Eric Leschinski

os provides you with a lot of these capabilities:

import os
os.path.isdir(dir_in) #True/False: check if this is a directory
os.listdir(dir_in)    #gets you a list of all files and directories under dir_in

the listdir will throw an exception if the input path is invalid.


R
Ramapati Maurya
#You can also check it get help for you

if not os.path.isdir('mydir'):
    print('new directry has been created')
    os.system('mkdir mydir')

python has builtin functions to create directories, so better use os.makedirs('mydir') instead of os.system(...)
You are printing that 'new directory has been created' but you do not know that. What if you do not have permissions to create a directory? You would print 'new directory has been created' but it would not be true. Would it.
G
Georgy

There is a convenient Unipath module.

>>> from unipath import Path 
>>>  
>>> Path('/var/log').exists()
True
>>> Path('/var/log').isdir()
True

Other related things you might need:

>>> Path('/var/log/system.log').parent
Path('/var/log')
>>> Path('/var/log/system.log').ancestor(2)
Path('/var')
>>> Path('/var/log/system.log').listdir()
[Path('/var/foo'), Path('/var/bar')]
>>> (Path('/var/log') + '/system.log').isfile()
True

You can install it using pip:

$ pip3 install unipath

It's similar to the built-in pathlib. The difference is that it treats every path as a string (Path is a subclass of the str), so if some function expects a string, you can easily pass it a Path object without a need to convert it to a string.

For example, this works great with Django and settings.py:

# settings.py
BASE_DIR = Path(__file__).ancestor(2)
STATIC_ROOT = BASE_DIR + '/tmp/static'

U
Uday Kiran

Two things

check if the directory exist? if not, create a directory (optional).

import os
dirpath = "<dirpath>" # Replace the "<dirpath>" with actual directory path.

if os.path.exists(dirpath):
   print("Directory exist")
else: #this is optional if you want to create a directory if doesn't exist.
   os.mkdir(dirpath):
   print("Directory created")

If you're going to do this then why not just os.mkdir() and catch (and ignore) FileExistsError. Your example has a time-of-check/time-of-use race. There is a non-zero delay between checking that dirpath exists and then taking action if it doesn't. In that time someone else could potentially make an object at dirpath and you'd have to deal with the exception anyway.
@AdamHawes, the solution is based on the query that was asked, the query specifically ask about "find if a directory exists", once the ` if os.path.exists ` is validated, it is up to the coder to decide on further proceedings, ` os.mkdir ` is only an assumptive action, hence I mentioned it as an option in the code.
u
user8133129

Step 1: Import the os.path module import the os.path module before running the code.

import os.path
from os import path

Step 2: Use path.exists() function The path.exists() method is used to find whether a file exists.

path.exists("your_file.txt")

Step 3: Use os.path.isfile() We can use the isfile command to determine whether or not a given input is a file.

path.isfile('your_file.txt')

step 4: Use os.path.isdir() We can use the os.path.dir() function to determine whether or not a given input is a directory.

path.isdir('myDirectory')

Here is the complete code

    import os.path
    from os import path
    
    def main():
    
       print ("File exists:"+str(path.exists('your_file.txt')))
       print ("Directory exists:" + str(path.exists('myDirectory')))
       print("Item is a file: " + str(path.isfile("your_file.txt")))
       print("Item is a directory: " + str(path.isdir("myDirectory")))
    
    if __name__== "__main__":
       main()

pathlibPath.exists() For Python 3.4

Pathlib Module is included in Python 3.4 and later versions to handle file system paths. Python checks if a folder exists using an object-oriented technique.

import pathlib
file = pathlib.Path("your_file.txt")
if file.exists ():
    print ("File exist")
else:
    print ("File not exist")

os.path.exists() – Returns True if path or directory does exists.

os.path.isfile() – Returns True if path is File.

os.path.isdir() – Returns True if path is Directory.

pathlib.Path.exists() – Returns True if path or directory does exists. (In Python 3.4 and above versions)