FastAPI + SQLAlchemy + Alembic (Todo app)

Simple todo API using FastAPI, SQLAlchemy, and Alembic migrations.

Setup

python -m venv .venv
source .venv/bin/activate
pip install -e .

Database (MySQL)

You can configure the connection either with DATABASE_URL or separate env vars:

export DB_NAME=todos
export DB_USERNAME=root
export DB_PASSWORD=""
export DB_HOST=127.0.0.1
export DB_PORT=3306
# or override everything with DATABASE_URL
# export DATABASE_URL="mysql+pymysql://user:pass@localhost:3306/todos"

Create the database (if not already):

mysql -u user -p -e "CREATE DATABASE IF NOT EXISTS todos CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;"

Run migrations:

alembic upgrade head

Run the API

uvicorn src.main:app --host 0.0.0.0 --port 8000 --reload

Endpoints

• GET / – health ping
• POST /todos – create a todo { "title": "Buy milk", "description": "...", "done": false }
• GET /todos – list todos
• GET /todos/{id} – fetch a single todo
• PATCH /todos/{id} – update fields (title, description, done)

Example update:

curl -X PATCH http://localhost:8000/todos/1 \
  -H "Content-Type: application/json" \
  -d '{"done": true}'