Getting Started – Project Overview

This project is a minimal REST API tutorial that demonstrates how to build a library service in Python 3.8 using Flask, Flask-RESTful, Flask-JWT, and Flask-SQLAlchemy on top of a SQLite database. It exposes CRUD endpoints for books and stores and includes JWT-based authentication and user registration. The main application entry point is PYTHON/app.py, which wires together the Flask app, API resources, authentication, and database models.

⚙️ Tech Stack

Below is an overview of the core technologies and libraries used:

📦 Project Structure

The repository’s key components are organized as follows:

• PYTHON/app.py

Main entry point. Configures Flask, JWT, database, and registers API endpoints.

• PYTHON/db.py

Initializes the shared SQLAlchemy instance.

• PYTHON/security.py

Defines authenticate and identity functions for JWT.

• PYTHON/models/
• BookModel, StoreModel, UserModel classes map to database tables.
• PYTHON/resources/
• Book, BookList, Store, StoreList, UserRegister RESTful resources handle HTTP requests and responses.
• PYTHON/postman-collections/
• Postman collection for quick endpoint testing.
• PYTHON/readme.md
• Setup instructions and example requests/responses.

How the Application Boots

Below is a simplified flow of what happens when you start the app:

flowchart TD
    A[Start: python app.py] --> B[Initialize Flask App]
    B --> C[Configure SQLAlchemy]
    C --> D[Register before_first_request create_tables]
    D --> E[Setup JWT /auth with authenticate & identity]
    E --> F[Register RESTful resources]
    F --> G[Run server on port 5000]

Key Initialization Snippet

The following excerpt from PYTHON/app.py shows how the application is configured and started:

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///data.db'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True
app.config['PROPAGATE_EXCEPTIONS'] = True
app.secret_key = 'SapanCrackle'

api = Api(app)

@app.before_first_request
def create_tables():
    db.create_all()

jwt = JWT(app, authenticate, identity)  # /auth

api.add_resource(Store, '/store/<string:name>')
api.add_resource(StoreList, '/stores')
api.add_resource(Book, '/book/<string:title>')
api.add_resource(BookList, '/books')
api.add_resource(UserRegister, '/register')

if __name__ == '__main__':
    from db import db
    db.init_app(app)
    app.run(port=5000, debug=True)

• Flask configuration sets up database URI and secret key.
• **create_tables()** ensures tables exist before any request.
• **JWT(app, authenticate, identity)** registers the /auth endpoint.
• **api.add_resource(...)** binds resources to URLs.

Component Relationships

The following Class Diagram illustrates core model relationships:

classDiagram
    BookModel  <|-- Resource : Book, BookList
    StoreModel <|-- Resource : Store, StoreList
    UserModel  <|-- Resource : UserRegister

    BookModel  : id
    BookModel  : title
    BookModel  : author
    BookModel  : isbn
    BookModel  : release_date
    BookModel  : price
    BookModel  : store_id

    StoreModel : id
    StoreModel : name

    UserModel  : id
    UserModel  : username
    UserModel  : password

    StoreModel "1" o-- "many" BookModel : contains

• **BookModel** and **StoreModel** are linked by a foreign key (store_id).
• **UserModel** is used for JWT-based authentication.
• Each Resource class interacts with its corresponding Model to handle CRUD operations.

This overview gives you the context needed to dive into individual components, explore the code, and extend the library service with new features.