IDP Data

Project Layout

Docker

This directory is mapped as a volume in the app. This can result in file permission errors like EACCES: permission denied. File permissions are generally based on UID integers and not usernames, so it doesn't matter what users are called, UIDs have to match or be mapped to the same numbers between the host and container.

We want to avoid running as root in production (even inside a container) and we want production to be as similar as possible to dev and test.

The easiest solution is to make this directory world-writable so that the container user can write to install/update stuff. Be aware of the security implications of this. e.g.

sudo find . -type d -exec chmod 777 '{}' \;
sudo find . -type f -exec chmod 774 '{}' \;

Another good option is to specify the user ID to run as in the container. A persistent way to do that is by specifying user: ${UID}:${GID} in a docker-compose.yml file, perhaps used as an overlay, and specifying your host user's IDs in an environment file used by docker-compose, e.g. .env.

Django

Apps go in the project directory idp_data

Python

Dependencies are managed via Pipfile in the docker container.

Add and lock dependencies in a temporary container:

docker-compose run --rm web pipenv install pkgname==1.2.3

Rebuild the image to contain the new dependencies:

docker-compose build web

Make sure to commit updates to Pipfile and Pipfile.lock to git

Javascript and CSS

JS and CSS are bundled using parcel - see package.json.

Dependencies are managed via yarn, e.g.

docker-compose run --rm web yarn add [email protected]

Make sure to commit updates to package.json and yarn.lock to git.

Development setup

In one shell, run the frontend asset builder

docker-compose run --rm web yarn dev

In another shell, initialise and run the django app

docker-compose run --rm web bin/wait-for-postgres.sh
docker-compose run --rm web python manage.py migrate
docker-compose up

If you need to destroy and recreate your dev setup, e.g. if you've messed up your database data or want to switch to a branch with an incompatible database schema, you can destroy all volumes and recreate them by running the following, and running the above again:

docker-compose down --volumes

Running tests

docker-compose run --rm web python manage.py test

Tests might fail to connect to the databse if the docker-compose db service wasn't running and configured yet. Just check the logs for the db service and run the tests again.

Settings

Undefined settings result in exceptions at startup to let you know they are not configured properly. It's one this way so that the defaults don't accidentally let bad things happen like forgetting analytics or connecting to the prod DB in development.

Key	Default	Type	Description
DATABASE_URL	undefined	String	postgresql://user:password@hostname/dbname style URL
DJANGO_DEBUG_TOOLBAR	False	Boolean	Set to True to enable the Django Debug toolbar NOT ON A PUBLIC SERVER!
DJANGO_SECRET_KEY	undefined	String	Set this to something secret and unguessable in production. The security of your cookies and other crypto stuff in django depends on it.
TAG_MANAGER_CONTAINER_ID	undefined	String	Google Tag Manager Container ID. Use this to set up Google Analytics.. Requried unless TAG_MANAGER_ENABLED is set to False
TAG_MANAGER_ENABLED	False	Boolean	Use this to disable the Tag Manager snippets, e.g. in dev or sandbox.