FastAPI + React Demo

Project: Simple product-tracking demo using FastAPI (backend) and a React frontend.

Deployments:

• Backend https://fastapi-inventory-management-system.onrender.com

• Frontend https://fastapi-inventory-management-system-1.onrender.com/

Note: Free PostgreSQL resets monthly on Render.
If backend is inactive, ping the app or recreate DB before testing.

Project snapshots:

• Backend UI image via Swagger UI
• Frontend

Purpose: Demonstrates a small CRUD API backed by SQLAlchemy and a create-react-app frontend that talks to the API.

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Prerequisites:

• Python 3.10+ (project uses a local venv at myFastAPienv).
• Node.js and npm (for the frontend).

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Quick Start (Backend)

• Create and activate the virtual environment (optional if myFastAPienv already exists):

python3 -m venv myFastAPienv
source myFastAPienv/bin/activate

• Install Python dependencies (FastAPI, Uvicorn, SQLAlchemy, DB driver):

pip install fastapi uvicorn sqlalchemy psycopg2

• Run the backend development server:

uvicorn main:app --reload

• Open the FastAPI interactive docs at: http://127.0.0.1:8000/docs

Notes:

• The backend code is in main.py. It defines CRUD endpoints for Product objects and uses SQLAlchemy models defined under database_models.py together with session helpers in database.py.
• On first run the code will create tables and initialize a few sample products if the database is empty.

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Quick Start (Frontend)

• Change to the frontend directory and install packages:

cd frontend
npm install

• Start the frontend (create-react-app):

npm start

• The frontend expects the backend at http://localhost:8000 (see frontend/package.json -> proxy). The React app runs by default at http://localhost:3000.

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Repository Structure

• main.py: FastAPI application with routes and DB initialization.
• database.py: SQLAlchemy session / engine helpers.
• database_models.py: SQLAlchemy ORM models and Base metadata.
• models.py: Pydantic models used by FastAPI request/response validation.
• frontend/: React app (create-react-app).
• setup.txt: Quick setup notes and useful commands.
• myFastAPienv/: Optional local Python virtual environment (not checked in normally).

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API Endpoints (summary from main.py)

• GET / — health check returns a welcome string.
• GET /products — list all products.
• GET /products/{id} — get product by id.
• POST /products — add a new product (accepts the Pydantic Product model payload).
• PUT /products/{id} — update an existing product.
• DELETE /products/{id} — delete a product by id.

Use the interactive docs at http://127.0.0.1:8000/docs to explore and test these endpoints.

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Database

• The project uses SQLAlchemy. The default DB connection is configured in database.py — by default that file may use SQLite or another engine depending on your configuration. If you're using PostgreSQL, install psycopg2 and set the correct connection URL in database.py.
• On first run, tables are created automatically via database_models.Base.metadata.create_all(bind=engine).

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Developer Notes

• The project includes a helper get_db() (dependency injection) to provide a DB Session to route handlers and ensure sessions are closed automatically.
• Sample data is inserted automatically if the products table is empty (see init_db() in main.py).

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