Working with docker

After installing docker, verify the "hello world" image. On fedora, the instructions are simply

$ sudo systemctl start docker
$ sudo docker run hello-world

To do build things with docker you will need to add yourself to the docker group

sudo usermod -aG docker $USER

You can try one of the variety of quickstart guides to make sure that your setup is otherwise working.

This configuration uses docker-compose and requires at least version 1.13. If the version in your OS repo is too old then the latest binaries can be found at https://github.com/docker/compose/releases.

Much of the following is heavily adapted from the docker django instructions and https://realpython.com/blog/python/django-development-with-docker-compose-and-machine/, which uses an example repo at https://github.com/realpython/dockerizing-django.

To start the services locally you will first need to create a .env file next to docker-compose.yml containing the the following information:

• DB_NAME
• DB_USER
• DB_PASS

Now start the services with:

$ bin/boot.sh

and the site will be viewable at localhost:8082.

The docker-compose exec command can be used to run commands within the various containers:

• start a shell:

$ docker-compose  exec web bash

• show details of the database volume

$ docker volume inspect pgdata

• start a shell and then attach the psql commandline tool:

$ docker-compose exec postgres bash
$ psql

• or look at the database directly

$ docker-compose exec -u postgres postgres psql

Then change to the correct database (defined in the .env file as django) and see the public tables

\c reports
\dt

• run commands directly with django's manage.py

$ docker-compose exec web bash

Delete things

remove containers

$ docker rm -f $(docker ps -a -q)

remove volumes

$ docker rm -v $(docker ps -a -q)

remove images

docker rmi $(docker images -q)

This article suggests just doing which will delete volumes as well.

$ docker system prune --volumes

Random things found in my browser and other places

• sqlectron is a desktop client for attaching to sql databases
• docker-compose rm removes stopped service containers. To list all volumes docker volume ls
• official phpmyadmin docker image
• adminer at github repo
• https://hub.docker.com/_/postgres/ says that you can add .sql scripts to /docker-entrypoint-initdb.d/ of the docker image and they will be run on startup