folder_size.py

# Script Name   : folder_size.py
# Author        : Craig Richards
# Created       : 19th July 2012
# Last Modified	: 22 February 2016
# Version       : 1.0.1

# Modifications : Modified the Printing method and added a few comments

# Description   : This will scan the current directory and all subdirectories and display the size.

import os
import sys      ''' Load the library module and the sys module for the argument vector'''
try:
    directory = sys.argv[1]   # Set the variable directory to be the argument supplied by user.
except IndexError:
    sys.exit("Must provide an argument.")

dir_size = 0    # Set the size to 0
fsizedicr = {'Bytes': 1,
             'Kilobytes': float(1) / 1024,
             'Megabytes': float(1) / (1024 * 1024),
             'Gigabytes': float(1) / (1024 * 1024
                                                                                                               *                                                                                                               1024)}
for (path, dirs, files) in os.walk(directory):      # Walk through all the directories. For each iteration, os.walk returns the folders, subfolders and files in the dir.
    for file in files:                              # Get all the files
        filename = os.path.join(path, file)
        dir_size += os.path.getsize(filename)       # Add the size of each file in the root dir to get the total size.

fsizeList = [str(round(fsizedicr[key] * dir_size, 2)) + " " + key for key in fsizedicr] # List of units

if dir_size == 0: print ("File Empty") # Sanity check to eliminate corner-case of empty file.
else:
  for units in sorted(fsizeList)[::-1]: # Reverse sort list of units so smallest magnitude units print first.
      print ("Folder Size: " + units)