starting a fake kubernetes cluster without docker or VMs

readme.md

Testing kubernetes manifests without a cluster or cluster

The start.sh script is using kwok and Go.

To delete the cluster: kowkctl delete cluster --name fake

start.sh

#!/usr/bin/env bash

set -exuo pipefail

command -v kwok > /dev/null || { echo "need to install kwok -> brew install kwok "; exit 1 ; }

TMP=~/tmp
KUBE_VERSION="v1.27.1"

function main {
  mkdir -p "$TMP" && cd "$TMP"
  
  wget https://dl.k8s.io/"$KUBE_VERSION"/kubernetes-src.tar.gz -O - | tar xz
  #
  # wget https://dl.k8s.io/"$KUBE_VERSION"/kubernetes-src.tar.gz && \
  # tar xzf kubernetes-src.tar.gz
  
  make WHAT=cmd/kube-apiserver
  make WHAT=cmd/kube-controller-manager
  make WHAT=cmd/kube-scheduler

  KUBE_BIN="$TMP/_output/local/bin/$(go env GOOS)/$(go env GOARCH)"
  
  kwokctl create cluster \
          --name fake \
          --runtime binary \
          --kube-admission \
          --kube-authorization \
          --kubeconfig "$TMP"/kubeconfig \
          --kube-controller-manager-binary "$KUBE_BIN"/kube-controller-manager \
          --kube-apiserver-binary "$KUBE_BIN"/kube-apiserver \
          --kube-scheduler-binary "$KUBE_BIN"/kube-scheduler
  
  pushd "$TMP" > /dev/null

  for i in $(seq 1 10);
  do
      export NODE="node-$i"
      cat << EOH >> node.yaml
---
apiVersion: v1
kind: Node
metadata:
  annotations:
    kwok.x-k8s.io/node: fake
    node.alpha.kubernetes.io/ttl: "0"
  labels:
    beta.kubernetes.io/arch: amd64
    beta.kubernetes.io/os: linux
    kubernetes.io/arch: arm64
    kubernetes.io/hostname: ${NODE}
    kubernetes.io/os: linux
    kubernetes.io/role: agent
    node-role.kubernetes.io/agent: ""
    type: kwok-controller
  name: ${NODE}
spec:
EOH
  
  
  done
  
  
  kubectl  --context kwok-fake --kubeconfig "$TMP"/kubeconfig apply -f "$TMP"/node.yaml
 
  echo
  echo "To access the cluster:"
  echo
  echo "    export KUBECONFIG=$TMP/kubeconfig"
  echo
  echo

}

main