Build/Run Helm Manager
Introduction
The helm manager is a service for managing helm charts. The service provides a REST API for onboarding of charts as well as installation and uninstallation of applications based on these charts.
In addition to the helm manager, a chart repository is used to store the available charts for onboarding and installation.
The Helm manager (and chart repo) can be executed in one of the following deployments:
As docker container on a local machine with kubernbetes
As kubernetes service and pod on a local machine with kubernetes or in minikube
As kubernetes service and pod on a kubernetes cluster
Prerequisites
The following need to be installed, latest version, on the machine
Kubernetes or minikube including kubectl
curl
git (if buidling image)
maven (if buidling image)
docker (for image build and image registry)
helm
Preparation
Clone the nonrtric repo from gerrit and change dir to helm-manager. Make sure to use the correct branch when cloning, use "master" until the branch for D Release is available.
All needed scripts for starting and running the helm manager, in docker or kubernetes are in this directory.
If the Helm Manager shall be installed in a kubernetes cluster the actions below shall be made on a node in cluster.
$ git clone "https://gerrit.o-ran-sc.org/r/nonrtric" -b <branch>
$ cd helm-managerBuild image
There is no need to build the image for the helm manager unless changes are made to the Dockerfile in the current dir.
If no changes are needed, skip this section.
Instruction to build the image, run the command blelow:
$ mvn clean packageThe built image should be named: o-ran-sc/nonrtric-helm-manager:1.0.0-SNAPSHOT. This can be be cah
$ docker images | grep helm
Expected output:
o-ran-sc/nonrtric-helm-manager 1.0.0-SNAPSHOT 56e50ade8c37 3 minutes ago 498MB
Note: Replace the image name in the docker-hm.sh and helm-manager if this image shall be used. For the helm-manager.ymal the parameters image and imagePullPolicy shall be configured like this:
image: o-ran-sc/nonrtric-helm-manager:1.0.0-SNAPSHOT
imagePullPolicy: NeverNote: Locally built images are not available to a kubernetes cluster unless the image is made available in an image repo accessible from within the cluster.
Create helm chart for test
Create a helm chart for this test. Package the chart into an archive. Run these two commands. The result should be a file named simple-app-0.1.0.tgz.
$ helm create simple-app
$ helm package simple-app
Run in kubernetes
This instruction is valid for running both in a local kubernetes and in a kubernetes ccluster
If running in a local kubernetes, set the env KUBE_HOST to the host of the kubernetes control plane
$ kubectl cluster-info
Kubernetes control plane is running at https://kubernetes.docker.internal:6443
$ KUBE_HOST="kubernetes.docker.internal"If running in a kubernetes cluster or in minikube, set the env KUBE_HOST to the ip of the kubernetes control plane.
Example
$ kubectl cluster-info
Kubernetes master is running at https://10.2.0.103:6443
$ KUBE_HOST=10.2.0.103Check if the nonrtric names space exists. If not, create the namespace
$ kubectl get ns nonrtric
$ kubectl create ns nonrtricStart the chartmuseum service and pod
$ kubectl apply -f kube-cm.yamlAdd the chart, created in the section 'Create helm for test', to the chartmuseum repo. The node port of the chartmuseum service is obtained and env var CM_PORT is assigned that port number.
$ CM_PORT=$(kubectl get svc chartrepo -n nonrtric -o jsonpath='{...ports[?(@.name=="'http'")].nodePort}')
$ curl --data-binary @simple-app-0.1.0.tgz -X POST http://$KUBE_HOST:$CM_PORT/api/charts
{"saved":true}
Create a service account for the helm manager. This example service account bind to the "cluster-admin" role which normally has full permissions to the add/change/read/delete any kubernetes object. It is advisable to bind the service account to a ClusterRole with less permissions if desired.
$ kubectl apply -f helm-manager-sa.yaml
serviceaccount/helm-manager-sa created
clusterrolebinding.rbac.authorization.k8s.io/helm-manager-sa-clusterrolebinding created
Start the helm manager. Four objects will be created. Note that the service is defined as a NodePort. This enables access from outside the cluster and is also a precondition for the test script to work. Change 'type' to 'ClusterIP' in the 'helmmanagerservice' service definition in the file helm-manager.yaml.
$ kubectl apply -f helm-manager.yaml
service/helmmanagerservice created
pod/helmmanagerservice created
persistentvolume/helm-manager-service-pv created
persistentvolumeclaim/helm-manager-service-pvc createdThe chartmuseum repo need to added to helm. This operation must be called with a url accessible from the helm manager pod.
Go into the helm manager container and add the repo.
$ kubectl exec -it helmmanagerservice -n nonrtric -- sh
# helm repo add cm http://chartrepo.nonrtric:8080
"cm" has been added to your repositories
$ exitThe helm manager is now running and configured with a chart repo.
Run the script test.sh to execute the sequence for installing the application 'simpleapp' namespace 'ckhm':
Namespace 'ckhm' is created in kubernetes if not existing
Onboard chart
Install chart
Uninstall chart
Remove (the onboarded) chart
All operations should report "OK".
$ ./test.sh kube $KUBE_HOSTExample output of the script
Cleanup of all created kubernetes object
$ kubectl delete -f helm-manager.yaml
service "helmmanagerservice" deleted
pod "helmmanagerservice" deleted
persistentvolume "helm-manager-service-pv" deleted
persistentvolumeclaim "helm-manager-service-pvc" deleted
$ kubectl delete -f kube-cm.yaml
service "chartrepo" deleted
pod "chartrepo" deleted
persistentvolume "chartrepo-pv" deleted
persistentvolumeclaim "chartrepo-pvc" deleted
$ kubectl delete -f helm-manager-sa.yaml
serviceaccount "helm-manager-sa" deleted
clusterrolebinding.rbac.authorization.k8s.io "helm-manager-sa-clusterrolebinding" deleted
Run in docker with local kubernetes
The helm-manger is possible to run as a docker container. However, a local kubernetes must be running where the application can be installed.
Create a private docker network, unless it already exists, for the containers to run in.
$ docker network create nonrtric-docker-netStart the chartmuseum container in a separate window. This will be used as a chart repository. Make note of the port, 8222, which will be available on local host. Charts uploaded to the chartmuseum container will be availed in the mounted dir 'charts' on your host.
$ ./docker-cm.shAdd the chart, created in the section 'Create helm for test', to the repo
$ curl --data-binary "@simple-app-0.1.0.tgz" -X POST http://localhost:8222/api/charts
{"saved":true}
Start the helm manager in a separate window. Make note of the port, 8112, which will be available on local host. This is the port to the Helm manager REST API.
$ ./docker-hm.shThe chartmusem repo need to added to helm. This operation must be called with a url accessible from the helm manager container.
Go into the helm manager container and add the repo.
$ docker exec -it helmmanagerservice sh
# helm repo add cm http://chartmuseum:8080
"cm" has been added to your repositories
$ exit
The helm manager is now running and configured with a chart repo.
Run the script test.sh to execute the sequence for installing the application 'simpleapp' namespace 'ckhm':
Namespace 'ckhm' is created in kubernetes if not existing
Onboard chart
Install chart
Uninstall chart
Remove (the onboarded) chart
All operations should report "OK".
$ ./test.sh dockerExpected oputput: