website/docs: add developer docs for frontend-only

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

website/developer-docs/full-dev-environment.md

@@ -0,0 +1,57 @@
+---
+title: Full development environment
+---
+
+## Backend
+
+To create a local development setup for authentik, you need the following:
+
+- Python 3.9
+- pipenv, which is used to manage dependencies, and can be installed with `pip install pipenv`
+- PostgreSQL (any recent version will do)
+- Redis (any recent version will do)
+
+For PostgreSQL and Redis, you can use the docker-compose file in `scripts/`. You can also use a native install, if you prefer.
+
+To configure authentik to use the local databases, create a file in the authentik directory called `local.env.yml`, with the following contents
+
+```yaml
+debug: true
+postgresql:
+  user: postgres
+
+log_level: debug
+secret_key: "A long key you can generate with `pwgen 40 1` for example"
+```
+
+Afterwards, you can start authentik by running `./manage.py runserver`. Generally speaking, authentik is a Django application.
+
+Most functions and classes have type-hints and docstrings, so it is recommended to install a Python Type-checking Extension in your IDE to navigate around the code.
+
+Before committing code, run `make lint` to ensure your code is formatted well. This also requires `pyright`, which can be installed with npm.
+
+Run `make gen` to generate an updated OpenAPI document for any changes you made.
+
+## Frontend
+
+By default, no transpiled bundle of the frontend is included. To build the UI, you need Node 12 or newer.
+
+The Frontend also uses a generated API client to talk with the backend. To generate this client, [openapitools/openapi-generator-cli](https://github.com/OpenAPITools/openapi-generator) is used.
+
+If you want to generate the client without installing anything, run this command:
+
+```shell
+make gen-web
+```
+
+To build the UI, run these commands:
+
+```
+cd web/
+npm i
+npm run build
+```
+
+If you want to make changes to the UI, run `npm run watch` instead.
+
+To ensure the code is formatted well, run `npx eslint . --fix` and `npm run lit-analyse`.