2.2 Using Helm Chart Repository

OCIR is an Open Container Initiative (OCI) Registry, and Helm 3 currently supports OCI Registry as an experimental (experimental) feature.

• https://helm.sh/docs/topics/registries/

Prepare the Helm CLI environment

1. Connect to Cloud Shell or work environment to use helm cli.

2. Install helm cli 3.7

   To register a chart in OCIR, the OCI Registry, use the helm push command provided by helm 3.7 to facilitate it. As of the document writing date, the helm cli version currently installed by default in Cloud Shell is 3.5.4, so 3.7 is additionally installed.

   wget https://get.helm.sh/helm-v3.7.1-linux-amd64.tar.gz
   tar -zxvf helm-v3.7.1-linux-amd64.tar.gz linux-amd64/helm
   mv linux-amd64/helm ~/.local/bin/
   

3. Register in PATH in .bashrc

   PATH=$HOME/.local/bin:$HOME/bin:$PATH
   

4. Activate OCI Support

   OCI Registry support in the helm cli is an experimental feature, and the following environment variables need to be set for use.

   export HELM_EXPERIMENTAL_OCI=1
   

Register Helm Chart after creation

Create a sample chart

Helm Chart Template Guide Try registering the sample chart created by following the example to OCIR.

1. Create a chart for testing.

   oke_admin@cloudshell:helm (ap-seoul-1)$ helm create mychart
   Creating mychart
   

2. Charting

   The generated chart is a sample chart that deploys nginx. For actual charting, I will modify it for the app, but for now, I just use it without modification as a deployment test.

3. Chart Packaging

   Package it with the helm package command.

   oke_admin@cloudshell:helm (ap-seoul-1)$ cd mychart
   oke_admin@cloudshell:mychart (ap-seoul-1)$ helm package .
   Successfully packaged chart and saved it to: /home/oke_admin/works/helm/mychart/mychart-0.1.0.tgz
   oke_admin@cloudshell:mychart (ap-seoul-1)$ ls
   charts Chart.yaml mychart-0.1.0.tgz templates values.yaml
   

OCIR Login and Helm Chart Push

Log in to OCIR using the same user and Auth Token as when logging in with the docker cli. See previous.

1. Log in with the helm cli in Cloud Shell or the connection environment through the Auth Token you created earlier.

   • OCIR address: <region-key>.ocir.io
     • region-key: Seoul Region is ap-seoul-1 or icn
     • Full Region Information: Availability by Region
   • username:
     • <tenancy-namespace>/<username> format
     • Username: The user name shown in the user profile in the OCI service console is used.
       1. User on Oracle Identity Cloud Service: <tenancy-namespace>/oracleidentitycloudservice/<username>
       2. OCI Local user: <tenancy-namespace>/<username>
     • tenancy-namespace: You can check the tenancy-namespace you checked when creating the Repository or oci os ns get in Cloud Shell.
   • Password: Auth Token of the user to log in created earlier

   oke_admin@cloudshell:mychart (ap-seoul-1)$ oci os ns get
   {
     "data": "cnrlxxxxxxxxx"
   }
   oke_admin@cloudshell:mychart (ap-seoul-1)$ helm registry login -u ${tenancy_namespace}/oke-admin ap-seoul-1.ocir.io
   Password:
   Login Succeeded
   

2. Helm Chart Push

   • To push to the Repository created in OCIR, simply push the format below. This will create a repository with repo-prefix/ .
     • <region-key>.ocir.io/<tenancy-namespace>/<repo-prefix>
   • mychart example

   oke_admin@cloudshell:mychart (ap-seoul-1)$ helm push ./mychart-0.1.0.tgz oci://ap-seoul-1.ocir.io/${tenancy_namespace}/helm
   Pushed: ap-seoul-1.ocir.io/cnrlxx3w0wgq/helm/mychart:0.1.0
   Digest: sha256:842486615ee4398001092a9b2f931320add0ecd13885e039427ce6f7926b493b
   

3. Check OCIR

   If you look at OCIR in the OCI service console, you can see that the pushed chart is registered normally. The example was pushed to the root compartment for convenience.

   • When pushing to a lower compartment, you must create a repository in advance. Ex) make your helm/mychart repository before push

   

Deploy Helm Chart to OKE Cluster

1. Connect to Cloud Shell or your work environment.

2. Deploy with the registered chart.

   helm install mychart oci://ap-seoul-1.ocir.io/${tenancy_namespace}/helm/mychart --version 0.1.0
   

3. Deployment example

   oke_admin@cloudshell:mychart (ap-seoul-1)$ helm install mychart oci://ap-seoul-1.ocir.io/${tenancy_namespace}/helm/mychart --version 0.1.0 --set service.type =LoadBalancer
   NAME: mychart
   LAST DEPLOYED: Fri Dec 3 15:17:51 2021
   NAMESPACE: default
   STATUS: deployed
   REVISION: 1
   NOTES:
   1. Get the application URL by running these commands:
        NOTE: It may take a few minutes for the LoadBalancer IP to be available.
              You can watch the status of by running 'kubectl get --namespace default svc -w mychart'
     export SERVICE_IP=$(kubectl get svc --namespace default mychart --template "{{ range (index .status.loadBalancer.ingress 0) }}{{.}}{{ end }}")
     echo http://$SERVICE_IP:80
   oke_admin@cloudshell:mychart (ap-seoul-1)$ kubectl get all
   NAME READY STATUS RESTARTS AGE
   pod/mychart-76677cc888-rl4v6 1/1 Running 0 55s
   
   NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
   service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 32m
   service/mychart LoadBalancer 10.96.198.136 146.xxx.xxx.xxx 80:30926/TCP 56s
   
   NAME READY UP-TO-DATE AVAILABLE AGE
   deployment.apps/mychart 1/1 1 1 56s
   
   NAME DESIRED CURRENT READY AGE
   replicaset.apps/mychart-76677cc888 1 1 1 55s
   

4. Check the distribution app access