Build a Backup Checker with Easy Archive and Easy Hash

Combine Easy Archive and Easy Hash to zip a note, restore it, and check whether the restored contents match the original. This is a small practice version of checking that a backup can actually be read back.

A small real-world example

Imagine saving your game ideas before editing them. This example creates its own temporary folder, so you can run it repeatedly without replacing your real notes. The folder and its files are removed when the example ends.

Install the package with python -m pip install py-simple-wrap, then run:

from pathlib import Path
from tempfile import TemporaryDirectory

from py_simple import extract_file_from_zip, hash_file, verify_file_hash, zip_files

with TemporaryDirectory() as workspace:
    folder = Path(workspace)
    note = folder / "ideas.txt"
    note.write_text("Build a moon garden game.\n", encoding="utf-8")
    original_checksum = hash_file(str(note))

    archive = zip_files([str(note)], str(folder / "ideas.zip"))
    restored = extract_file_from_zip(archive, "ideas.txt", str(folder / "restored"))

    print("Restored note matches:", verify_file_hash(restored, original_checksum))

    Path(restored).write_text("Build an underwater garden game.\n", encoding="utf-8")
    print("Edited note matches:", verify_file_hash(restored, original_checksum))

Example output:

Restored note matches: True
Edited note matches: False

What happened?

hash_file() records a SHA-256 checksum of the original file's bytes. Keep this value from before editing: calculating a new checksum after changing the file would give you a different baseline.

zip_files() puts the note into a ZIP archive. With this single input, the archive member is named ideas.txt, without its temporary parent path. extract_file_from_zip() restores that member into a separate directory and returns the restored file's path. We extract only the archive we just created in this example.

verify_file_hash() compares the restored file with the saved checksum. The first check succeeds. After we change the restored note, the second check fails. A missing or unreadable file raises EasyHashError rather than returning False; False means the checksum did not match.

Try it yourself

Add another note to the list passed to zip_files(). Record its checksum, restore it by its own filename, and check that one too. Keep filenames distinct so each archive member is easy to identify.

Why use these helpers?

The standard-library version needs ZIP member handling and checksum calculation code. These helpers let you focus on the useful sequence: save a baseline, archive, restore, and compare. For more examples, see Easy Archive and Easy Hash.