Helm Installation

First you’ve to install Helm 3. You can grab a precompiled binary from the releases page on GitHub. Once downloaded and extracted, you can either move the binary into your PATH, or create a symlink pointing to the executable. I’ve created a symlink called helm3 which will I use during the upcoming snippets.

cd ~/Downloads
# Download Helm3 Beta3
wget https://get.helm.sh/helm-v3.0.0-beta.3-darwin-amd64.tar.gz

# verify checksum
shasum -a 256 -c <<< "88ef4da17524d427b4725f528036bb91aaed1e3a5c4952427163c3d881e24d77 *helm-v3.0.0-beta.3-darwin-amd64.tar.gz"

# extract into ~/Downloads/helm3
mkdir helm3
tar -xzf helm-v3.0.0-beta.3-darwin-amd64.tar.gz --directory helm3

# create a symlink
ln -s ~/Downloads/helm3/darwin-amd64/helm /usr/bin/helm3

Verify Helm 3 installation

Because Tiller is gone, all you have to verify is the local installation using:

helm3 version

version.BuildInfo
{
  Version:"v3.0.0-beta.3",
  GitCommit:"5cb923eecbe80d1ad76399aee234717c11931d9a",
  GitTreeState:"clean",
  GoVersion:"go1.12.9"
}

Create a Chart and deploy it to Kubernetes

First let’s use the create sub command to create a new Application Chart.

cd ~/dev
helm3 create hello-helm3

Take a close look at the generated Chart.yaml it explicitly specifies the type as Application. If you want to create a reusable Library Chart, you have to change the type setting to library and remove the templates.

For the sake of this article, let’s stick with the simple Application Chart and bring our application to Kubernetes.

Helm3 allows multiple releases having the same name. For separation we will use regular Kubernetes namespaces.

# create two sample namespace
kubectl create namspace helm3-ns1
kubectl create namespace helm3-ns2

kubectl get ns | grep helm3
helm3-ns1         Active   3s
helm3-ns2         Active   2s

Having the namspaces in place, use helm3 install to install the previously created Chart to both namespaces.

cd ~/dev

helm3 install sample-deployment hello-helm3 -n helm3-ns1
helm3 install sample-deployment hello-helm3 -n helm3-ns2

Helm will provide some basic information about the deployment job for every deployment.

Helm Releases deployed to Kubernetes

Verify the releases using helm3 list:

helm3 list --all-namespaces

List all currently deployed releases with Helm 3

Every deployment is tracked using a Kubernetes Secret in the same Namespace.

kubectl get secret -n helm3-ns1

NAME                   TYPE                                  DATA   AGE
sample-deployment.v1   helm.sh/release                       1      1m26s

Modify the Chart and perform an upgrade

For demonstration purpose, udate the hello-helm3 Chart and set replicaCount: 2 in values.yaml. Remember to bump the version in Chart.yaml

helm3 upgrade sample-deployment hello-helm3 -n helm3-ns1

Helm will now upgrade the sample-deployment in Kubernetes Namespace helm3-ns1. As part of the upgrade process, a new Secret (sample-deployment.v2) will be deployed to the Namespace. In fact, Helm3 secrets contain the entire release in encrypted form. Once again, you can verify the overall state using helm3 list --all-namespaces

Helm 3 Listing different release revisions

Clean up the Kubernetes Cluster

You can clean up your Kubernetes cluster usign helm3 uninstall, which will remove all Helm 3 artifacts from the currrent namespace.

helm3 uninstall sample-deployment -n helm3-ns1
helm3 uninstall sample-deployment -n helm3-ns2

kubectl delete ns helm3-ns1
kubectl delete ns helm3-ns2

Playground: Docker Image

If you want to play around with Helm 3 today, you can either install on of the pre-compiled beta binaries on your system, or you can use a tiny Docker Image. I have created and published it to the public Docker Hub at thorstenhans/helm3.

You can pull it directly via docker pull thorstenhans/helm3; further instructions are available in the Readme.