How to create a great local Python development environment with Docker, and a TODO application.

1. Why Docker?

2. Dockerize an app

FROM python:3.10-slim
WORKDIR /code
COPY ./requirements.txt ./
RUN pip install --no-cache-dir --upgrade -r requirements.txt
COPY ./src ./src
CMD ["uvicorn", "src.main:app", "--host", "0.0.0.0", "--port", "80", "--reload"]

docker build -t fastapi-image .
docker run --name fastapi-container -p 80:80 fastapi-image
docker run -d --name fastapi-container -p 80:80 fastapi-image

3. Immediate file changes (volumes)

 docker stop fastapi-container
 docker ps -a
 docker rm fastapi-container
 docker run -d --name fastapi-container -p 80:80 -v $(pwd):/code fastapi-image

4. Use the IDE to jump into a python venv

python -m venv venv
. venv/bin/activate
pip install -r requirements.txt

uvicorn src.main:app --reload

deactivate

5. Docker Compose

services:
 app:
 build: .
 container_name: python-server
 command: uvicorn src.main:app --host 0.0.0.0 --port 80 --reload
 ports:
 - 80:80
 - 5678:5678
 volumes:
 - .:/code

docker-compose up
docker-compose down

6. Add more services (Redis)

services:
 app:
 ...
 depends_on:
 - redis
 redis:
 image: redis:alpine

7. Debug Python code inside a container

import debugpy
debugpy.listen(("0.0.0.0", 5678))
# print("Waiting for client to attach...")
# debugpy.wait_for_client()

services:
 app:
 ...
 ports:
 - 80:80
 - 5678:5678

8. Docs are generated from FastAPI

Try a Python version easily with Docker

 docker pull python:3.11-slim
 docker run -d -i --name python_dev python:3.11-slim
 docker exec -it python_dev /bin/sh

Further Resources:

Other commands for cleaning up

docker rm container_name
docker image rm image_name
docker system prune
docker images prune

du -sh *