TempBerry - Temperature Monitor for Raspberry PI

This project contains the backend for the Raspberry PI Temperature monitor. It is written in Python (3.5+) and uses the following components/packages/libraries:

• Django 2.2 (powered by unicorns)
• Django Rest Framework 3.10 (provides a wonderful REST API)
• Whitenoise (for serving static files)
• gunicorn (running django)
• Redis / Django-Redis for some caching
• MySQL/Postgres as a database backend (Postgres is preferred though)

Please note that this project is work in progress, comes without warranty, and should definately only be used for experimenting and as a learning resource, but not for any production use.

Content

This repo contains the following pieces:

• a python script that collects temperatures from "any" source using pilight (see receive.py)
• a Django backend that allows collecting temperature data (see app folder)
• a docker-compose setup for development (see docker-compose.yml and the docker folder)
• a kubernetes setup for production deployments (see deploy folder)

There is also a rudimentary frontend application available at https://gitlab.com/ckreuzberger/tempberry-frontend.

Development Setup using Docker

To start development locally, build the docker images and run migrations

docker-compose build
docker-compose run --rm python python manage.py migrate

Consider adding a Django Superuser for the Django Admin Panel using

docker-compose run --rm python python manage.py createsuperuser

Finally, start it up using

docker-compose up

You should be able to access the backend using http://127.0.0.1:8000/, the API using http://127.0.0.1:8000/api/ and the Django Admin Panel using http://127.0.0.1:8000/admin/.

Production Setup using Kubernetes

Deployment Files are in the deploy/ subfolder.

Make sure to add the .env file as follows: (todo: this is not implemented yet...)

kubectl create configmap tempberry-backend-config --from-file=.env

Then apply the Kubernetes yaml files for the Postgres database using

kubectl apply -f deploy/postgres-storage.yaml
kubectl apply -f deploy/postgres-credentials.yaml
kubectl apply -f deploy/postgres.yaml

Verify that you can connect to the Postgres Server using

kubectl port-forward svc/postgres 5432:5432

Then apply the tempberry backend deployment yaml using

kubectl apply -f deploy/tempberry-backend.yaml

and also apply an ingress (this requires you to have a working ingress gateway, e.g. nginx-ingress):

kubectl apply -f deploy/tempberry-backend-ingress.yaml

Once the pods are ready, run the migrations using

kubectl exec -it deployment/tempberry-backend python manage.py migrate

Finally, create a superuser using

kubectl exec -it deployment/tempberry-backend python manage.py createsuperuser

Production Setup using SystemD

This requires Python 3.5 and virtualenv to be pre-installed on your system.

1. Create a new virtualenv for python 3.5 and activate it
2. Install requirements using pip install -r requirements.txt
3. Run migrations, create superuser, etc...
4. Copy .env.example to a .env file and edit the values according to your setup
5. Set up a systemd service unit with the following content

   [Unit]
   Requires=tempberry_gunicorn.socket
   Description=gunicorn daemon for tempberry
   After=network.target
    
   [Service]
   # make sure a runtime directory is accessible from the outside
   RuntimeDirectoryMode=0775
   PIDFile=%h/.%p.pid
   # define working directory (%h = home directory)
   WorkingDirectory=%h/tempberry/app
   Environment="DJANGO_SETTINGS_MODULE=tempBerry.settings.live"
   EnvironmentFile=%h/tempberry/.env
   ExecStart=%h/tempberry/venv/bin/gunicorn --pid %h/.%p.pid --workers 4 --log-level debug --bind 127.0.1.1:5001 tempBerry.wsgi 
   ExecReload=/bin/kill -s HUP $MAINPID
   ExecStop=/bin/kill -s TERM $MAINPID
   
   
   # security hardening
   # see https://gist.github.com/ageis/f5595e59b1cddb1513d1b425a323db04
   # make sure the following permissions are only applied for ExecStart, but not for ExecReload/ExecStop
   PermissionsStartOnly=True
   
   NoNewPrivileges=yes
   PrivateTmp=yes
   ProtectSystem=strict
   ProtectControlGroups=yes
   RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6 AF_NETLINK
   RestrictRealtime=yes
   RestrictNamespaces=yes
   MemoryDenyWriteExecute=yes
   
   # disabled as they cause issues with gunicorn
   #PrivateDevices=yes
   #DevicePolicy=closed
    
   [Install]
   WantedBy=multi-user.target
   

6. Set up a systemd socket unit:

   [Unit]
   Description=gunicorn socket for tempberry
    
   [Socket]
   ListenStream=127.0.1.1:5001
    
   [Install]
   WantedBy=sockets.target
   

Enable the socket and the service, and start the socket. Accesing the socket (using port 5001) should automatically start the service.

License

The source code within this repository is made available using the MIT License. See LICENSE.

Contributions

As this is more of a hobby project for myself, I do not expect any contributions. Please do not expect any Pull Requests to be merged (except for minor changes such as bugfixes or typo fixes).