Exercise 09-36:
Using the os.walk function, create a program that calculates the space occupied per directory, generating an HTML page with the results.
Answer:
##############################################################################
# Python From Scratch
# Author: Nilo Ney Coutinho Menezes
# Editora Novatec (c) 2010-2025 - LogiKraft 2025
# Site: https://pythonfromscratch.com
# ISBN: 978-85-7522-949-1 (Paperback), 978-85-7522-950-7 (hardcover), 978-85-7522-951-4 (ebook)
#
# File: chapter 09/exercise-09-36.py.py
##############################################################################
import sys
import os
import os.path
import math
# This function converts the size
# into more readable units, avoiding
# returning and printing very large values.
def size_to_human_readable(size):
if size == 0:
return "0 byte"
magnitude = math.log(size, 10)
if magnitude < 3:
return f"{size} bytes"
elif magnitude < 6:
return f"{size / 1024.0:7.3f} KB"
elif magnitude < 9:
return f"{size / pow(1024, 2)} MB"
elif magnitude < 12:
return f"{size / pow(1024, 3)} GB"
style_mask = "'margin: 5px 0px 5px %dpx;'"
def generate_style(level):
return style_mask % (level * 30)
# Returns a function where the nroot parameter is used
# to calculate the indentation level
def generate_level_and_style(root):
def level(path):
xlevel = path.count(os.sep) - nroot
return generate_style(xlevel)
nroot = root.count(os.sep)
return level
# Uses os.walk to traverse directories
# And a stack to store the size of each directory
def generate_listing(page, directory):
directory = os.path.abspath(directory)
# indenter is a function that calculates how many levels
# from the directory level a path should have.
indenter = generate_level_and_style(directory)
stack = [[directory, 0]] # Guard element, to avoid empty stack
for root, directories, files in os.walk(directory):
# If the current directory: root
# Is not a subdirectory of the last traversed
# Pop until finding a common parent
while not root.startswith(stack[-1][0]):
last = stack.pop()
page.write(
f"<p style={indenter(last[0])}>Size: (size_to_human_readable(last[1]))</p>"
)
stack[-1][1] += last[1]
page.write(f"<p style={indenter(root)}>{root}</p>")
d_size = 0
for f in files:
full_path = os.path.join(root, f)
d_size += os.path.getsize(full_path)
stack.append([root, d_size])
# If the stack has more than one element
# pop them
while len(stack) > 1:
last = stack.pop()
page.write(
f"<p style={indenter(last[0])}>Size: ({size_to_human_readable(last[1])})</p>"
)
stack[-1][1] += last[1]
if len(sys.argv) < 2:
print("Enter the directory name to collect files!")
sys.exit(1)
directory = sys.argv[1]
page = open("files.html", "w", encoding="utf-8")
page.write(
"""
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Files</title>
</head>
<body>
"""
)
page.write(f"Files found starting from directory: {directory}")
generate_listing(page, directory)
page.write(
"""
</body>
</html>
"""
)
page.close()