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Kubernetes development

These instructions assume a Debian development environment.

No considerations are made in these instructions and notes around system security.

It is possible to run HDS on Kubernetes. This is an ideal way to test-run the system because it is ultimately deployed in Kubernetes.

Preparation

In this example, podman is used as the build system for container images.

In this example, we are using the k3s system to get a small cluster working on a lab machine running Debian trixie. Install a simple k3s system so that there is a basic lab K8S system to work with.

To allow a local user to access the cluster using kubectl, the config needs to be made available. In this example, the current user is added to a new group and then the config file is made available to that group.

sudo groupadd k3s
sudo adduser "${USER}" k3s

Now edit /etc/systemd/system/k3s.service adding the following lines;

K3S_KUBECONFIG_MODE="640"
K3S_KUBECONFIG_GROUP="k3s"

Restart the host and observe the permissions on the /etc/rancher/k3s/k3s.yaml file;

-rw-r----- 1 root k3s ... /etc/rancher/k3s/k3s.yaml

Now the kubectl command should be able to be used by your regular user.

Deploy database into the Kubernetes cluster

Load the manifest YAML files into the Kubernetes cluster in order to stand up the resources required to run the Postgres database server.

kubectl apply \
-f ./support/local-k8s-kind-development/haikudepotserver-pg-configmap.yaml \
-f ./support/local-k8s-kind-development/haikudepotserver-pg-volume.yaml \
-f ./support/local-k8s-kind-development/haikudepotserver-pg-app.yaml

Wait a short while for the system to settle and then check that the database is running.

kubectl get pods

A pod with prefix haikudepotserver-pg should be listed and eventually 1/1 should be up.

Deploy graphics services application into the Kubernetes cluster

The HDS system manipulates graphics files as part of its operation. This functionality is supported by a container image that contains tools and an application server that provides an API to those tools. This application can be deployed with;

kubectl apply -f ./support/local-k8s-kind-development/haikudepotserver-server-graphics.yaml

Wait a short while for the system to settle and then check that the application is running.

kubectl get pods

A pod with prefix haikudepotserver-haikudepotserver-server-graphics should be listed and eventually 1/1 should be up.

Deploy application into the Kubernetes cluster

Later when you wish to import the packages from a repository, the process can be time-consuming and require a large volume of traffic. To reduce the quantity of packages imported, an additional environment variable HDS_REPOSITORY_IMPORT_ALLOWEDPKGNAMEPATTERN can be set in the file ./support/local-k8s-kind-development/haikudepotserver-webapp.yaml to something like ^.[Aa].+$ in order to only import those packages that have the second character as "A" in their name.

Also in the same YAML file, the image key should be upgraded to the latest release of the HDS application. You can find the latest version here.

Now we deploy the application into the Kubernetes cluster.

kubectl apply -f ./support/local-k8s-kind-development/haikudepotserver-webapp.yaml

Wait a short while for the system to settle and then check that the application is running.

kubectl get pods

A pod with prefix haikudepotserver-webapp should be listed and eventually 1/1 should be up.

The application can be accessed on http://localhost:30080 on the development host. Login as root with password zimmer.

Get a psql session on the Postgres database

Get the name of the database pod; in this example haikudepotserver-pg-f6d69987b-lsjkc then run the following;

kubectl exec -it haikudepotserver-pg-f6d69987b-lsjkc -- \
psql --password -U haikudepotserver haikudepotserver

Get application logs

kubectl --context kind-haikudepotserver logs deployment/haikudepotserver-webapp -f

Build locally, deploy to the local cluster

In the sample files...

  • haikudepotserver-webapp.yaml
  • haikudepotserver-server-graphics.yaml

...you will see that a remote image is specified for the application. For example, ghcr.io/haiku/haikudepotserver:1.0.160. If you want to run a locally built container image, first build the images. This is done by creating the Dockerfile-s and then building the contains and tagging them.

make dockerfiles
docker build -f Dockerfile_webapp --load --tag haikudepotserver:999.999.999 .
docker build -f Dockerfile_server_graphics --load --tag haikudepotserver-server-graphics:999.999.999 .

Once this build is complete, export the images to tar files;

podman save --output /tmp/haikudepotserver-9.tar haikudepotserver:999.999.999
podman save --output /tmp/haikudepotserver-server-graphics-9.tar haikudepotserver-server-graphics:999.999.999

Now transport them to the k3s Kubernetes node's host disk system at /var/lib/rancher/k3s/agent/images.

Change the image specified in the Kubernetes Deployment manifests;

  • in the haikudepotserver-webapp.yaml set the image to haikudepotserver:999.999.999
  • in the haikudepotserver-server-graphics.yaml set the image to haikudepotserver-server-graphics:999.999.999

and then re-apply these two manifests to the cluster.

Setup and import a repository

  1. Authenticate as root to the web interface
  2. Visit the list of repositories
  3. Add a new repository with code haikuports, name HaikuPorts
  4. Add a new repository source with code haikuports_x86_64
  5. Add a new repository source mirror with URL https://eu.hpkg.haiku-os.org:443/haikuports/master/x86_64/current
  6. Choose the "Trigger import" link on the repository source view
  7. Observe the logs from the HDS application 
    kubectl --context kind-haikudepotserver logs deployment/haikudepotserver-webapp -f
  8. Wait for the import process to complete with the message ...(repositoryhpkringress); finish in the logs
  9. View the web interface home page and observe that packages are listed