kubectl: install and run KWOK

kwok.md

kubectl: install and run KWOK

Installation

# install KWOK
KWOK_WORK_DIR=$(mktemp -d)
KWOK_REPO=kubernetes-sigs/kwok
KWOK_LATEST_RELEASE=$(curl "https://api.github.com/repos/${KWOK_REPO}/releases/latest" | jq -r '.tag_name')
cat <<EOF > "${KWOK_WORK_DIR}/kustomization.yaml"
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
images:
  - name: registry.k8s.io/kwok/kwok
    newTag: "${KWOK_LATEST_RELEASE}"
resources:
  - "https://github.com/${KWOK_REPO}/kustomize/kwok?ref=${KWOK_LATEST_RELEASE}"
EOF
kubectl kustomize "${KWOK_WORK_DIR}" > "${KWOK_WORK_DIR}/kwok.yaml"
kubectl apply -f "${KWOK_WORK_DIR}/kwok.yaml"

Create fake nodes:

for i in {0..10}
do
kubectl apply -f - <<EOF
apiVersion: v1
kind: Node
metadata:
  annotations:
    node.alpha.kubernetes.io/ttl: "0"
    kwok.x-k8s.io/node: fake
  labels:
    beta.kubernetes.io/arch: amd64
    beta.kubernetes.io/os: linux
    kubernetes.io/arch: amd64
    kubernetes.io/hostname: kwok-node-${i}
    kubernetes.io/os: linux
    kubernetes.io/role: agent
    node-role.kubernetes.io/agent: ""
    type: kwok
  name: kwok-node-${i}
spec:
  taints: # Avoid scheduling actual running pods to fake Node
    - effect: NoSchedule
      key: kwok.x-k8s.io/node
      value: fake
status:
  allocatable:
    cpu: 32
    memory: 256Gi
    pods: 110
  capacity:
    cpu: 32
    memory: 256Gi
    pods: 110
  nodeInfo:
    architecture: amd64
    bootID: ""
    containerRuntimeVersion: ""
    kernelVersion: ""
    kubeProxyVersion: fake
    kubeletVersion: fake
    machineID: ""
    operatingSystem: linux
    osImage: ""
    systemUUID: ""
  phase: Running
EOF
done

Create fake pods:

kubectl apply -f - <<EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  name: fake-pod
  namespace: default
spec:
  replicas: 100
  selector:
    matchLabels:
      app: fake-pod
  template:
    metadata:
      labels:
        app: fake-pod
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
              - matchExpressions:
                  - key: type
                    operator: In
                    values:
                      - kwok
      # A taints was added to an automatically created Node.
      # You can remove taints of Node or add this tolerations.
      tolerations:
        - key: "kwok.x-k8s.io/node"
          operator: "Exists"
          effect: "NoSchedule"
      containers:
        - name: fake-container
          image: fake-image
EOF