Helm

Helm is a really cool way to install and upgrade applications on Kubernetes. Its kinda like Homebrew package manager for OS X but for Kubernetes.

We've been patching helm so that it can work with OpenShift Templates and adding Secret generation.

The patches are all in the openshift-all branch of helm. You can download the binaries if you want to play.

Using Vagrant

We include helm in our vagrant image here. So that if you recreate your vagrant image you can install/upgrade any app in fabric8. e.g. type this:

helm upgrade fabric8/cd-pipeline

and it'll install/upgrade the CD Pipeline chart.

Using any OpenShift or Kubernetes environment

Just download the binary for your platform, add it to your $PATH and type:

helm update
helm repo add fabric8 https://github.com/fabric8io/charts.git

Now helm will be pointed at the fabric8 chart repository so you can search, installor upgrade the fabric8 charts.

Using Helm

Helm refers to applications as charts which you can then search, install, upgrade or delete in a particular namespace in kubernetes.

Once you have got helm installed using one of the above mechansims here's how you use it:

Installing a chart

All the fabric8 charts begin with the name fabric8/.

So to install a particular chart name, such as fabric8/cd-pipeline type:

help install fabric8/cd-pipeline

which will install the CD Pipeline chart.

Note that helm install tends to fail if it finds any resources that already exist; so use helm upgrade instead; which creates or upgrades depending on whats already installed!

Upgrading a chart

After you have installed a chart a new release can come along from time to time. So when a new fabric8 release comes out if you want to upgrade your installation type:

helm update
helm upgrade fabric8/cd-pipeline

and it upgrades, recreating/updating all the kubernetes resources!

Helm looks and feels kinda like homebrew; so helm update pulls down all the latest git repos of the charts (helm speak for 'apps`). e.g. all our fabric8 charts are here: https://github.com/fabric8io/charts