A Python script to mass add same extension to all files in a folder.

mass_add_same_extension.py

# This is a Python script to mass add same
# extension for all files in a folder.
import os
import shutil
import sys

def MassAddSameExtension(_targDir, _ext):

    # Get the list of all files in the targetDirectory.
    targDirList = os.listdir(_targDir)
    #print(targDirList)

    # Remove everything that is directory/folder.
    targDirListWithoutFolder = []
    for fileOrFolder in targDirList:

        absPathToFileOrFolder = os.path.join(
            _targDir, fileOrFolder)

        if not os.path.isdir(absPathToFileOrFolder):
            targDirListWithoutFolder.append(absPathToFileOrFolder)

    for file in targDirListWithoutFolder:

        #print(file)

        # Split the text into file name and its extension.
        fileName, ext = os.path.splitext(file)

        print(fileName)
        #print(ext)

        # Check if the second argument has a dot or not.
        # If the second argument has a dot already, then
        # do not put additional dot in the front of the
        # extension. If the second argument has no dot,
        # then add dot in front of the extension name.
        #print(str(_ext[:1]))
        newExt = str(_ext) if str(_ext)[:1] == "." else str("." + _ext)
        #print(newExt)

        # Construct new name with new extension
        # provided from the second argument.
        #print(fileName)
        newName = fileName + newExt
        #print(newName)

        # Make absolute paths for the old name and
        # the new name.
        oldAbsPath = os.path.join(_targDir, file)
        newAbsPath = os.path.join(_targDir, newName)
        #print(oldAbsPath)
        #print(newAbsPath)

        # Rename the files.
        print("renamed " + str(file) + " into " + str(newName))
        shutil.move(oldAbsPath, newAbsPath)

if __name__ == "__main__":

    MassAddSameExtension(sys.argv[1], sys.argv[2])