Simple Social Media API

A FastAPI-based social media backend API built according to the Product Requirements Document. This API allows users to create, retrieve, update, and delete posts; add comments; and like/unlike posts.

Features

• Posts Management: Create, read, update, and delete posts
• Comments System: Add, read, update, and delete comments on posts
• Likes System: Like and unlike posts
• SQLite Database: Persistent storage with automatic initialization
• OpenAPI Documentation: Auto-generated Swagger UI and ReDoc
• CORS Support: Enabled for all origins for development

Project Structure

python/
├── main.py           # FastAPI application entry point
├── models.py         # SQLModel data models and schemas
├── database.py       # Database configuration and session management
├── api.py           # API route handlers and business logic
├── sns_api.db       # SQLite database file (created automatically)
├── test_api.sh      # Comprehensive API test script
├── .venv/           # Python virtual environment
└── README.md        # This file

Setup and Installation

1. Virtual Environment: Already set up with uv

   source .venv/bin/activate

2. Dependencies: Installed via uv

   • FastAPI
   • SQLModel (includes SQLAlchemy and Pydantic)
   • Uvicorn (ASGI server)

Running the Application

Start the Server

# Activate virtual environment
source .venv/bin/activate

# Start the server
uvicorn main:app --host 0.0.0.0 --port 8000

# Or with auto-reload for development
uvicorn main:app --host 0.0.0.0 --port 8000 --reload

The API will be available at: http://localhost:8000

API Documentation

• Swagger UI: http://localhost:8000/docs
• ReDoc: http://localhost:8000/redoc
• OpenAPI JSON: http://localhost:8000/openapi.json

API Endpoints

Posts

• GET /api/posts - List all posts
• POST /api/posts - Create a new post
• GET /api/posts/{post_id} - Get a specific post
• PATCH /api/posts/{post_id} - Update a post
• DELETE /api/posts/{post_id} - Delete a post

Comments

• GET /api/posts/{post_id}/comments - List comments for a post
• POST /api/posts/{post_id}/comments - Create a comment
• GET /api/posts/{post_id}/comments/{comment_id} - Get a specific comment
• PATCH /api/posts/{post_id}/comments/{comment_id} - Update a comment
• DELETE /api/posts/{post_id}/comments/{comment_id} - Delete a comment

Likes

• POST /api/posts/{post_id}/likes - Like a post
• DELETE /api/posts/{post_id}/likes - Unlike a post

Example Usage

Create a Post

curl -X POST http://localhost:8000/api/posts \
  -H "Content-Type: application/json" \
  -d '{
    "username": "john_doe",
    "content": "Just had an amazing hike in the mountains! #outdoorlife"
  }'

Add a Comment

curl -X POST http://localhost:8000/api/posts/{post_id}/comments \
  -H "Content-Type: application/json" \
  -d '{
    "username": "jane_smith", 
    "content": "Great photo! Where was this taken?"
  }'

Like a Post

curl -X POST http://localhost:8000/api/posts/{post_id}/likes \
  -H "Content-Type: application/json" \
  -d '{
    "username": "mike_wilson"
  }'

Testing

Run the comprehensive test script:

./test_api.sh

This script tests all major API functionality including creating posts, comments, and likes.

Database

• Type: SQLite
• File: sns_api.db
• Initialization: Automatic on application startup
• Schema: Defined using SQLModel with proper relationships and constraints

Architecture

• Framework: FastAPI with SQLModel
• Database ORM: SQLAlchemy (via SQLModel)
• Validation: Pydantic (via SQLModel)
• ASGI Server: Uvicorn
• CORS: Enabled for all origins
• Documentation: Auto-generated OpenAPI 3.1.0 spec

Compliance

This implementation strictly follows the provided OpenAPI specification and Product Requirements Document:

• ✅ All endpoints implemented as specified
• ✅ Proper HTTP status codes (200, 201, 204, 400, 404, 500)
• ✅ JSON request/response format
• ✅ Data validation and error handling
• ✅ SQLite database with automatic initialization
• ✅ CORS enabled for all origins
• ✅ Port 8000 as specified
• ✅ Swagger UI and OpenAPI documentation
• ✅ No authentication (as specified in requirements)