TandoorRecipes/docs/install/kubernetes.md

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!!! info "Community Contributed"
This guide was contributed by the community and is neither officially supported, nor updated or tested.
## K8s Setup
This is a setup which should be sufficient for production use. Be sure to replace the default secrets!
## Files
### 10-configmap.yaml
The nginx config map. This is loaded as nginx.conf in the nginx sidecar to configure nginx to deliver static content.
### 15-secrets.yaml
!!! warning "Contains secrets"
**Replace them!**
This file is only here for a quick start. Be aware that changing secrets after installation will be messy and is not documented here. **You should set new secrets before the installation.** As you are reading this document **before** the installation ;-)
Create your own postgresql passwords and the secret key for the django app.
See also [Managing Secrets using kubectl](https://kubernetes.io/docs/tasks/configmap-secret/managing-secret-using-kubectl/)
**Replace** `db-password`, `postgres-user-password` and `secret-key` **with something - well - secret :-)**
~~~
echo -n 'db-password' > ./db-password.txt
echo -n 'postgres-user-password' > ./postgres-password.txt
echo -n 'secret-key' | sha256sum | awk '{ printf $1 }' > ./secret-key.txt
~~~
Delete the default secrets file `15-secrets.yaml` and generate the K8s secret from your files.
~~~
kubectl create secret generic recipes \
--from-file=postgresql-password=./db-password.txt \
--from-file=postgresql-postgres-password=./postgres-password.txt \
--from-file=secret-key=./secret-key.txt
~~~
### 20-service-account.yml
Creating service account `recipes` for deployment and stateful set.
### 30-pvc.yaml
The creation of the persistent volume claims for media and static content. May you want to increase the size. This expects to have a storage class installed.
### 40-sts-postgresql.yaml
The PostgreSQL stateful set, based on a bitnami image. It runs a init container as root to do the preparations. The postgres container itself runs as a lower privileged user. The recipes app uses the database super user (postgres) as the recipes app is doing some db migrations on startup, which needs super user privileges.
### 45-service-db.yaml
Creating the database service.
### 50-deployment.yaml
The deployment first fires up a init container to do the database migrations and file modifications. This init container runs as root. The init container runs part of the [boot.sh](https://github.com/TandoorRecipes/recipes/blob/develop/boot.sh) script from the `vabene1111/recipes` image.
The deployment then runs two containers, the recipes-nginx and the recipes container which runs the gunicorn app. The nginx container gets it's nginx.conf via config map to deliver static content `/static` and `/media`. The guincorn container gets it's secret key and the database password from the secret `recipes`. `gunicorn` runs as user `nobody`.
Currently, this deployment is using the `latest` image. You may want to explicitly set the tag, e.g.
~~~
image: vabene1111/recipes:1.4.7
~~~
It is **extremely important** to use the same image in both the initialization `init-chmod-data` and the main `recipes` containers.
### 60-service.yaml
Creating the app service.
### 70-ingress.yaml
Setting up the ingress for the recipes service. Requests for static content `/static` and `/media` are send to the nginx container, everything else to gunicorn. TLS setup via cert-manager is prepared. You have to **change the host** from `recipes.local` to your specific domain.
## Conclusion
All in all:
- The database is set up as a stateful set.
- The database container runs as a low privileged user.
- Database and application use secrets.
- The application also runs as a low privileged user.
- nginx runs as root but forks children with a low privileged user.
- There's an ingress rule to access the application from outside.
I tried the setup with [kind](https://kind.sigs.k8s.io/) and it runs well on my local cluster.
There is a warning, when you check your system as super user:
!!! warning "Media Serving Warning"
Serving media files directly using gunicorn/python is not recommend! Please follow the steps described here to update your installation.
I don't know how this check works, but this warning is simply wrong! ;-) Media and static files are routed by ingress to the nginx container - I promise :-)
## Updates
These manifests have been tested for several releases. Newer versions may not work without changes.
If everything works as expected, the `init-chmod-data` initialization container performs the database migration and the update procedure is transparent. However, it is recommended to use specific tags to increase stability and avoid unnecessary migrations.
## Apply the manifets
To apply the manifest with kubectl, use the following command:
~~~
kubectl apply -f ./docs/install/k8s/
~~~