FastAPI User Authentication API (Module 10)

📌 Overview

This project is a FastAPI-based user management API that demonstrates secure user creation, validation, password hashing, and automated testing. It follows best practices for API design, testing, and CI/CD.

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🚀 Features

• User creation endpoint (POST /users/)
• Input validation using Pydantic
• Secure password hashing (no plain-text storage)
• Duplicate user prevention
• Integration and unit testing with pytest
• Continuous Integration using GitHub Actions

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🛠️ Tech Stack

• FastAPI
• Python 3.12
• SQLAlchemy
• Pydantic
• Passlib (bcrypt)
• Pytest
• GitHub Actions (CI/CD)

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📂 Project Structure

app/
  ├── models.py        # Database models
  ├── schemas.py       # Pydantic schemas
  ├── crud.py          # Database operations
  ├── auth.py          # Password hashing logic

tests/
  ├── test_auth.py
  ├── test_schemas.py
  ├── test_users_integration.py

.github/workflows/
  └── test.yml         # CI pipeline

main.py                # FastAPI app entry point
requirements.txt

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▶️ Running the Application

1. Create virtual environment

python -m venv venv

2. Activate environment

# Windows
venv\Scripts\activate

# Mac/Linux
source venv/bin/activate

3. Install dependencies

pip install -r requirements.txt

4. Run the server

uvicorn main:app --reload

5. Open in browser

http://127.0.0.1:8000/docs

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🧪 Running Tests

pytest

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🔐 API Endpoint

Create User

POST /users/

Request Body

{
  "username": "user1",
  "email": "user1@example.com",
  "password": "password123"
}

Response

{
  "id": 1,
  "username": "user1",
  "email": "user1@example.com"
}

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⚠️ Error Handling

Duplicate User

{
  "detail": "Username or email already exists"
}

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🔄 CI/CD

This project uses GitHub Actions to automatically run tests on every push.

• Workflow file: .github/workflows/test.yml
• Ensures all tests pass before code is considered valid

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🐳 Docker Setup & Deployment

This project is containerized using Docker for easy setup and deployment.

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📦 Build Docker Image

From the root of the project directory, run:

docker build -t YOUR_DOCKER_USERNAME/fastapi-auth-api .

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▶️ Run Docker Container

docker run -d -p 8000:8000 YOUR_DOCKER_USERNAME/fastapi-auth-api

Then open:

http://127.0.0.1:8000/docs

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📤 Push to Docker Hub

1. Log in to Docker:

docker login

2. Push your image:

docker push sh8733/module10-fastapi-auth

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🔗 Docker Hub Repository

https://hub.docker.com/repository/docker/sh8733/module10-fastapi-auth/general

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📌 Notes

• Ensure Docker Desktop is running before building the image
• The container runs the FastAPI app using Uvicorn
• Port 8000 is exposed for API access
• Update YOUR_DOCKER_USERNAME with your actual Docker Hub username

📌 Notes

• Passwords are securely hashed using bcrypt
• Sensitive data (passwords) are never returned in API responses
• The database file (test.db) is ignored to prevent test conflicts

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🔗 Useful Links

• FastAPI Docs: https://fastapi.tiangolo.com/
• Pytest Docs: https://docs.pytest.org/
• GitHub Actions: https://docs.github.com/actions

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