🔐 SecureAuth Backend (FastAPI)

A production-style authentication system built with FastAPI, featuring secure password hashing, JWT-based login, and protected routes.

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🚀 Overview

This project implements a complete authentication flow used in real-world backend systems:

• User registration with password hashing
• Secure login with credential validation
• JWT token generation
• Token-based protected routes

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⚡ Features

• 🔐 User Signup (hashed passwords)
• 🔑 Login with JWT token
• 🛡️ Token Verification
• 🚫 Unauthorized access handling
• 📦 Modular architecture (Auth separated cleanly)

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🧱 Tech Stack

• ⚡ FastAPI
• 🐍 Python
• 🗄️ SQLite
• 🧠 SQLAlchemy ORM
• 🔐 JWT (python-jose)
• 🔒 Password Hashing

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📂 Project Structure

src/
├── auth/
│   ├── controllers.py
│   ├── routers.py
│   ├── schemas.py
│   └── utils.py
│
├── users/
│   ├── models.py
│   ├── schemas.py
│   ├── controllers.py
│   └── routers.py
│
├── utils/
│   ├── db.py
│   └── settings.py
│
└── main.py

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🔥 API Endpoints

👤 Users

• POST /users/ → Register user

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🔐 Auth

• POST /auth/login → Login & get token
• GET /auth/me → Protected route (requires token)

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🧪 Example Login Response

{
  "access_token": "your.jwt.token",
  "token_type": "bearer"
}

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🔐 How Authentication Works

User → Login → Token Generated
      ↓
Client stores token
      ↓
Client sends token in headers
      ↓
Server verifies token
      ↓
Access granted / denied

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⚙️ Setup & Run

git clone https://github.com/your-username/secureauth-backend.git
cd secureauth-backend

python -m venv venv
source venv/bin/activate

pip install -r requirements.txt

uvicorn src.main:app --reload

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📚 API Docs

Swagger UI:

👉 http://127.0.0.1:8000/docs

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🧠 What I Learned

• Implementing authentication from scratch
• Secure password handling
• Token-based authorization flow
• Dependency-based security in FastAPI
• Writing modular backend architecture

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🚀 Future Improvements

• 🔐 Role-Based Access Control
• ♻️ Refresh Tokens
• 🗄️ PostgreSQL integration
• 🌍 Deployment

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👨‍💻 Author

Building secure backend systems step by step 🚀