samsafadi / csua-backend

A backend for the CSUA interblags.

CSUA-backend

A backend for the CSUA interblags.

Current Maintainer: Robert Quitt [email protected]

User Workflow

1. Create a fork of this repo
2. Clone your fork to your local/development machine
3. Install dependencies locally
4. Make changes locally, test, repeat
5. Commit those changes
6. Push commits to your fork
7. Make a pull request

Installation

1. Install Python 3
2. Install Django and dependencies with pip3 install --user -r requirements.txt
3. Create your .env file by copying .env.dev, e.g. cp .env.dev .env
4. Set up local db with python3 manage.py migrate

• Visit the admin page at http://127.0.0.1:8000/admin/ to add a semester object

5. Run server with python3 manage.py runserver
6. Navigate web browser to http://127.0.0.1:8000/
7. Create admin user with python3 manage.py createsuperuser

Making changes to database models

1. Make changes to db_data/models.py
2. python3 manage.py makemigrations on your development machine
3. python3 manage.py migrate to apply new migrations to your local db
4. Commit and push your changes to models.py as well as generated migrations/
5. Pull latest changes on remote machine
6. python3 manage.py migrate on remote machine to update database with latest models
7. Run sudo systemctl reload csua-backend-gunicorn on the remote machine so the changes take effect

Editing/Creating/Deleting Data

Go to https://www.csua.berkeley.edu/admin/ to edit data!

Repo structure

Django's online documentation has more detail on a project's structure

• apps/
  • This Django project is divided into "apps" (i.e. main_page/, db_data/, etc.)
  • csua_backend/ holds the projects's configurations
  • Each app is divided into:
    • migrations/ lists the changes that have been made to the database models
    • __init__.py just tells python the app is a python module
    • admin.py details how db models should be viewed in the admin interface
    • apps.py probably says that this directory is an app
    • models.py contains the database models of the app
    • tests.py has unit tests to test the apps functionality
    • urls.py says what URLs route to which views
    • views.py has functions that serve a "view" (webpage)
• fixtures/ contains database fixtures to record and bootstrap content and various database data
• media_root/ is where user-uploaded files are served from
• requirements.txt lists the required python packages for this project.
• static_root/ is where static files are served from (many of which come from ./static/ and are moved here by manage.py's collectstatic)
• templates/ holds the html templates that are populated and served by views
• manage.py is a command-line script for performing actions on the project

Dumping database data into json:

python3 manage.py dumpdata db_data > fixtures/$(date +db_data-%m%d%y.json)

Deploying

(Option 1) Deploy a new change from GitHub to tap

1. ssh into tap.csua.berkeley.edu
2. Change directory to the project directory
3. git pull
4. python3 manage.py collectstatic to update static images
5. If you're making changes to the db models, follow those instructions too

(Option 2) Deploy to tap using fabric

1. fab -H <user>@tap.csua.berkeley.edu deploy
2. Profit

Deployment Details

• This Django app runs as on a gunicorn server on tap.
• The gunicorn process is managed by systemd and the service file is located at /etc/systemd/system/csua-backend-gunicorn.service
  • This service can be manipulated with systemctl
    • To reload the wsgi app, run sudo systemctl reload csua-backend-gunicorn
• tap runs debian 9.8 (stretch), we are using Python 3.5. This may change in the near future, as I (Robert) just installed Python 3.6 from source. This means you cannot use any Python 3.6+ features such as:
  • formatted string literals (f-strings) (e.g. print(f"Oh yea yea {globals()}"))
  • Underscores in numeric literals (e.g. 69_420_000)
  • Typing hints (e.g. primes: List[int] = [])
• The app is behind an Nginx proxy.
  • Nginx serves the static and media files, homedirs, and forwards all other requests to the app.
  • https://github.com/CSUA/services-nginx/blob/master/sites-available/www.csua.berkeley.edu
  • /etc/nginx/sites-available/www.csua.berkeley.edu
• mysqlclient is installed and necessary for deployment on tap

LDAP Details

tap runs an OpenLDAP server. It is accessible from anywhere over TLS on port 636.

For an LDAP client to connect, it must accept our self-signed certificate. Usually this is done by adding this line to /etc/ldap/ldap.conf:

TLS_REQCERT allow