Example: Kubernetes with KinD¶

You may need to access Kubernetes within your build. KinD is a popular option, and easy to run in an action.

Certified for:

x86_64
arm64 including Raspberry Pi 4

Use a private repository if you're not using actuated yet

GitHub recommends using a private repository with self-hosted runners because changes can be left over from a previous run, even when using Actions Runtime Controller. Actuated uses an ephemeral VM with an immutable image, so can be used on both public and private repos. Learn why in the FAQ.

Try out the action on your agent¶

Create a new file at: .github/workflows/build.yml and commit it to the repository.

Note that it's important to make sure Kubernetes is responsive before performing any commands like running a Pod or installing a helm chart.

name: build

on: push
jobs:
  start-kind:
    runs-on: actuated-4cpu-16gb
    steps:
      - uses: actions/checkout@master
        with:
          fetch-depth: 1
      - name: get arkade
        uses: alexellis/setup-arkade@v1
      - name: get kubectl and kubectl
        uses: alexellis/arkade-get@master
        with:
          kubectl: latest
          kind: latest
      - name: Create a KinD cluster
        run: |
          mkdir -p $HOME/.kube/
          kind create cluster --wait 300s
      - name: Wait until CoreDNS is ready
        run: |
          kubectl rollout status deploy/coredns -n kube-system --timeout=300s
      - name: Explore nodes
        run: kubectl get nodes -o wide
      - name: Explore pods
        run: kubectl get pod -A -o wide
      - name: Show kubelet logs
        run: docker exec kind-control-plane journalctl -u kubelet

To run this on ARM64, just change the actuated prefix from actuated- to actuated-arm64-.

Using a registry mirror for KinD¶

Whilst the instructions for a registry mirror work for Docker, and for buildkit, KinD uses its own containerd configuration, so needs to be configured separately, as required.

When using KinD, if you're deploying images which are hosted on the Docker Hub, then you'll probably need to either: authenticate to the Docker Hub, or configure the registry mirror running on your server.

Here's an example of how to create a KinD cluster, using a registry mirror for the Docker Hub:

#!/bin/bash

kind create cluster --wait 300s --config /dev/stdin <<EOF
kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
containerdConfigPatches:
- |-
    [plugins."io.containerd.grpc.v1.cri".registry.mirrors."docker.io"]
    endpoint = ["http://192.168.128.1:5000"]
EOF

With open source projects, you may need to run the build on GitHub's hosted runners some of the time, in which case, you can use a check whether the mirror is available:

curl -f --connect-timeout 0.1 -s http://192.168.128.1:5000/v2/_catalog &> /dev/null

if [ "$?" == "0" ]
then
  echo "Mirror found, configure KinD for the mirror"
else
  echo "Mirror not found, use defaults"
fi

To use authentication instead, create a Kubernetes secret of type docker-registry and then attach it to the default service account of each namespace within your cluster.

The OpenFaaS docs show how to do this for private registries, but the same applies for authenticating to the Docker Hub to raise rate-limits.

You may also like Alex's alexellis/registry-creds project which will replicate your Docker Hub credentials into each namespace within a cluster, to make sure images are pulled with the correct credentials.