Test-Driven Development with FastAPI and Docker

Based on the awesome Test-Driven Development with FastAPI and Docker course from testdriven.io, with a few changes: Management of python dependencies is done withpyenv and poetry (v2) instead of pip; Instead of the general Package registry with a PAT, we used the GitHub Container registry ghcr.io the more secure GITHUB_TOKEN; and we used docker compose (the docker-compose-plugin) instead of docker-compose (the older standalone version).

Workflow

Build

In the repo root directory (where the docker-compose.yml is) build the containers with:

$ docker compose up -d --build

View container logs

$ docker compose logs web

Bring down and remove volumes:

$ docker compose down -v

Database

$ docker compose exec web aerich init -t app.db.TORTOISE_ORM

Init:

$ docker compose exec web aerich init-db

Upgrade:

$ docker compose exec web aerich upgrade

Access the database via psql with:

$ docker compose exec web-db psql -U postgres

Then connect to the database with:

postgres=# \c web_dev
postgres=# \dt
postgres=# select * from textsummary;
postgres=# \q

Running tests

With the containers up and running, run the tests:

$ docker compose exec web python -m pytest

Coverage report:

$ docker compose exec web python -m pytest --cov="."

Code quality

$ docker compose exec web black .

$ docker compose exec web flake8 .

$ docker compose exec web isort .

With checks:

$ docker-compose exec web black . --check
$ docker-compose exec web isort . --check-only

Troubleshooting

Internal Server Error

$ docker compose logs web
...
fastapi-tdd-docker-web-1  | tortoise.exceptions.OperationalError: relation "textsummary" does not exist

When building a fresh docker container with db and app, make sure to execute migration script during the container building.