Python Library Manager

A simple Python console app for tracking books. You can add, list, update, and delete books. This project is for beginners learning Python.

Features

1. List books
2. Add a new book
3. Mark a book as read or unread
4. Delete a book
5. Exit

Functions

• load_books — load books from the JSON file
• save_books — save books to the JSON file
• list_books — show all books
• add_book — add a new book
• change_status — change read / unread status
• delete_book — delete a book
• show_menu — show the menu
• main — start the program

Technologies

• Python 3
• Standard library only (json)
• UTF-8 file reading and writing

No third-party packages. No requirements.txt.

Files

python-library-manager/
├── book.py        # main app
├── README.md      # project info
├── .gitignore
└── books.json     # created after the first save

How to Run

python3 book.py

Menu

--- BOOK TRACKER ---
1. List Books
2. Add New Book
3. Mark Read/Unread
4. Delete Book
5. Exit
Your choice (1-5):

JSON Storage

Books are saved in books.json:

{
    "title": "Crime and Punishment",
    "author": "Dostoevsky",
    "read": false
}

The file is created after the first successful change. Saved books stay after you close and open the app again.

Error Handling

The app does not crash if:

• the JSON file is missing or broken
• the menu choice is invalid
• the book number is not a number
• the book number is 0, negative, or too big
• the title or author is empty
• the book list is empty

Manual Test Checklist

• Start without books.json
• List books when empty
• Add a valid book
• Try empty title / empty author
• Change status to read, then unread
• Enter bad book numbers (letters, 0, negative, too big)
• Delete a book
• Try delete when empty
• Restart and check saved books
• Add special characters and check JSON
• Start with a broken JSON file
• Enter a menu choice outside 1-5

Possible Later Features

• Search by title or author
• Sort books
• Rating (1-5)
• Book category
• Show only unread books