🗂️ Contact Manager API

⚠️ Live Demo: Currently unavailable because the hosted database instance has expired.
FastAPI-based contact manager API with PostgreSQL, featuring CRUD operation and encrypted data handling.

🚧 Project Status: In Progress

📌 Navigate

• Features
• Architecture
• Tech Stack
• Project Structure
• Setup Instructions
• Project Evolution
• Feedback Welcome

Features

• 🗂️ CRUD API
  • Create Contact: Adds a new contact
    • POST /contacts
  • Get a single contact: Retrieves the contact number of a single contact by name
    • GET /contacts/{contact_id}
  • Get all contacts data: Retrieves all the encrypted contact numbers from the Database, decrypts them all, and returns them
    • GET /contacts
  • Update contact entry: Updates an existing contact in the database, updates the encryption key
    • PUT /contacts/{contact_id}
  • Delete contact entry: Deletes an existing contact in the database, cleans the encryption key
    • DELETE /contacts/{contact_id}
• 🔐 Encryption
  • Contact numbers are encrypted using Fernet (symmetric encryption)
  • Master Key securely stored in .env file
• 🐳 Containerization & Deployment
  • Dockerized FastAPI application
  • Multi-container setup using Docker Compose
  • Persistent PostgreSQL storage using Docker volumes
  • Deployed on Render with managed PostgreSQL integration
• ⚙️ Backend Architecture
  • Database layer
  • Service layer
  • Endpoint layer
• 📄 API Development & Documentation
  • Documented using Bruno (local-first API client)
  • Interactive API documentation provided by FastAPI Swagger UI
• 📜 Logging
  • Used python's in-built logging module for adding logging to my codebase
  • Logs capture key events across all layers
• 🧪 Testing
  • Used PyTest and FastAPI's TestClient to test all CRUD endpoints
  • Added unit tests for encryption and decryption utility functions
  • Verified API responses, status codes, and encrypted data handling
• 🌿 Git Workflow
  • Feature-based branching
  • Separate branches for debugging and enhancements

Architecture

Tech Stack

• Programming Language: Python
• Web Framework: FastAPI
• Database: PostgreSQL and SQLite (development/testing)
• ORM: SQLAlchemy
• Validation: Pydantic
• Encryption: Fernet (cryptography)
• Containerization: Docker, Docker Compose
• Deployment & Hosting: Render
• Testing: PyTest, FastAPI TestClient
• Logging: Python logging module
• API Testing & Documentation: Bruno
• Version Control: Git

Project Structure

.

├── alembic/
├── app/
│   ├── database/
│   ├── main.py # FastAPI application entry point
│   ├── routes.py
│   ├── schemas.py
│   └── services/
├── config/
├── docs/
|── tests/
├── Dockerfile
├── requirements.txt

Setup Instructions

1. Clone the repository:

git clone https://github.com/aarya095/Contact-Manager.git
cd Contact-Manager

2. Create environment file:

• Create a .env.main file in the project root:
• Set sample env variables as follows:

DATABASE_URL = sqlite:///dev.db
MASTER_KEY="OjVDJ1YVzBxrBAKiJfxXoAihMzVqbMQNm-kKvoltEJs="

3. Start the application:

• docker compose up --build

4. Access the application:

• Frontend:
  • http://127.0.0.1:8000/
• API Documentation:
  • http://127.0.0.1:8000/docs

Running Without Docker

1. Follow the first two instructions from the above setup.

2. Create a virtual environment:

• Windows
  • python -m venv venv
  • venv\Scripts\activate
• Linux/macOS
  • python3 -m venv venv
  • source venv/bin/activate

3. Install dependencies:

• pip install -r requirements.txt

4. Set .env_file path:

• In the config/config.py, set env_file_path to .env.main

5. Run the server:

• uvicorn app.main:app --reload

6. Access the application:

• Frontend:
  • http://127.0.0.1:8000/
• API Documentation:
  • http://127.0.0.1:8000/docs

Project Evolution

This project originally started as a CLI-based Contact Manager application.

You can find the CLI version in the cli branch: https://github.com/aarya095/Contact-Manager/tree/menu-driven-cli

After converting the app into an API, I first implemented a unique encryption key for each contact, with keys stored in the .env file. However, while preparing to Dockerize the app, I realized this approach wasn’t practical. I then simplified the design to use a single master encryption key stored in .env.

The per-contact encryption implementation is available in the feature/per-contact-env-keys branch: https://github.com/aarya095/Contact-Manager/tree/feature/per-contact-env-keys

Feedback Welcome

I'm actively learning backend development with Python and FastAPI.

If you notice improvements related to:

• Code organization
• API design
• Naming conventions
• Python best practices
• Performance
• Testing

I'd greatly appreciate your feedback or suggestions.

Author: Aarya Sarfare