Find all files in a directory with extension .txt

Question

How can I find all the files in a directory having the extension .txt in python?

Answer 1

Here's more versions of the same that produce slightly different results:

glob.iglob()

import glob
for f in glob.iglob("/mydir/*/*.txt"): # generator, search immediate subdirectories 
    print f

glob.glob1()

print glob.glob1("/mydir", "*.tx?")  # literal_directory, basename_pattern

fnmatch.filter()

import fnmatch, os
print fnmatch.filter(os.listdir("/mydir"), "*.tx?") # include dot-files

Answer 2

Use glob.

>>> import glob
>>> glob.glob('./*.txt')
['./outline.txt', './pip-log.txt', './test.txt', './testingvim.txt']

Answer 3

A copy-pastable solution similar to the one of ghostdog:

def get_all_filepaths(root_path, ext):
    """
    Search all files which have a given extension within root_path.

    This ignores the case of the extension and searches subdirectories, too.

    Parameters
    ----------
    root_path : str
    ext : str

    Returns
    -------
    list of str

    Examples
    --------
    >>> get_all_filepaths('/run', '.lock')
    ['/run/unattended-upgrades.lock',
     '/run/mlocate.daily.lock',
     '/run/xtables.lock',
     '/run/mysqld/mysqld.sock.lock',
     '/run/postgresql/.s.PGSQL.5432.lock',
     '/run/network/.ifstate.lock',
     '/run/lock/asound.state.lock']
    """
    import os
    all_files = []
    for root, dirs, files in os.walk(root_path):
        for filename in files:
            if filename.lower().endswith(ext):
                all_files.append(os.path.join(root, filename))
    return all_files

Answer 4

In case the folder contains a lot of files or memory is an constraint, consider using generators:

def yield_files_with_extensions(folder_path, file_extension):
   for _, _, files in os.walk(folder_path):
       for file in files:
           if file.endswith(file_extension):
               yield file

Option A: Iterate

for f in yield_files_with_extensions('.', '.txt'): 
    print(f)

Option B: Get all

files = [f for f in yield_files_with_extensions('.', '.txt')]

Answer 5

Use fnmatch: https://docs.python.org/2/library/fnmatch.html

import fnmatch
import os

for file in os.listdir('.'):
    if fnmatch.fnmatch(file, '*.txt'):
        print file

Answer 6

Python v3.5+

Fast method using os.scandir in a recursive function. Searches for all files with a specified extension in folder and sub-folders.

import os

def findFilesInFolder(path, pathList, extension, subFolders = True):
    """  Recursive function to find all files of an extension type in a folder (and optionally in all subfolders too)

    path:        Base directory to find files
    pathList:    A list that stores all paths
    extension:   File extension to find
    subFolders:  Bool.  If True, find files in all subfolders under path. If False, only searches files in the specified folder
    """

    try:   # Trapping a OSError:  File permissions problem I believe
        for entry in os.scandir(path):
            if entry.is_file() and entry.path.endswith(extension):
                pathList.append(entry.path)
            elif entry.is_dir() and subFolders:   # if its a directory, then repeat process as a nested function
                pathList = findFilesInFolder(entry.path, pathList, extension, subFolders)
    except OSError:
        print('Cannot access ' + path +'. Probably a permissions error')

    return pathList

dir_name = r'J:\myDirectory'
extension = ".txt"

pathList = []
pathList = findFilesInFolder(dir_name, pathList, extension, True)