docker-compose.override.yml

services:
  backend:
    container_name: dev-backend
    # "manage.py" is the default Django app management tool. `runserver` starts the development server on the specified host and port using Django's built-in webserver.
    # Django's development server is not suitable for production; you'll need to replace the command with either gunicorn, nginx, or heroku at some point just before production
    command: python manage.py runserver 0.0.0.0:8000
    # the volume is a bind mount, meaning whatever changes we make on the host machine will be reflected in the host container
    # [source]:[target] Meaning, that the backend folder in the container is bind mounted to the backend directory
    volumes:
      - ./Backend:/backend
    # the ports are [host]:[container] . This means that the host machine will be listening to 8000 port and the container will be listening to the 8000 port as well.
    # https://docs.docker.com/compose/compose-file/compose-file-v3/#ports
    ports:
      - 8000:8000
    # Volumes are mounted, meaning any changes made on the host machine will be reflected in the containers which mount the volume
    # [source]:[target] Meaning, that the backend folder in the container is bind mounted to the backend directory
    depends_on:
      - db
  db:
    platform: linux/amd64
    # 12 is used instead of 13 due to post-gis docker documentation
    image: postgis/postgis
    # By default, PostgreSQL databases are named the same as the user which creates them. If the user exists, then the db is named after the user. To keep it simple, it's best to name one or the other.
    # Because there are workarounds required when the user is named other than postgres, to keep things simple, I'll just use the default user and make sure there is a good password.
    # <Postgres database user was here prior to security update>

    # The database password is a required parameter.
    # "trust" authentication is set up by default on the database service, which means anyoneone who has access to that container is assumed to also be authorized to access the database, so no password will be required.
    # However, we need this password when connecting from outside the container, so it will be needed from the Django settings file
    # <Postgres database password was here prior to security update>

    # By default this is md5, which is the "intermediate" form of security available. I should consider upgrading to scram_sha256 later as it is the most secure.
    # https://www.postgresql.org/docs/current/auth-password.html
    # POSTGRES_HOST_AUTH_METHOD
    env_file:
      - ./Database/env/.env.dev
    ports:
      - 5432:5432
    container_name: dev-db
    volumes:
      # the name of the host source container is postgres_data. The container-destination is the second part. This will be where the data will be stored on my local machine.
      - postgres_data:/var/lib/postgresql/data/
    ports:
      - 5432:5432
  frontend:
    container_name: dev-frontend
    command: ["npm", "start"]
    volumes:
      - ./Frontend:/frontend
    ports:
      - 3000:3000
  # for when the time comes.
  # the book says we need a volume within the db service and a volume outside of the db service...
      # it's totally possible to just create a new volume every time, but it's simple extension of code to make it so that the volume is available to multiple services.
      # For example, what if we wanted another container that backs up the data of the volume?
      # https://docs.docker.com/compose/compose-file/compose-file-v3/#volume-configuration-reference
volumes:
  postgres_data: