kubectl-shell-pod.yaml

---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: kubectl-access
  namespace: dmrub
---
kind: Pod
apiVersion: v1
metadata:
  name: kubectl-shell
  namespace: dmrub
spec:
  serviceAccountName: kubectl-access
  containers:
  - name: shell
    image: ubuntu:latest
    command:
      - "/bin/sh"
    env:
      - name: KUBECTL_ARCH
        value: amd64
      - name: KUBECTL_VERSION
        value: v1.21.0
    args:
      - -c
      - >-
        set -xe;
        export DEBIAN_FRONTEND=noninteractive;
        apt-get update;
        apt-get install -y ca-certificates curl bash bash-completion;
        if [ ! -f /data/kubectl ]; then
          curl -sL "https://dl.k8s.io/release/${KUBECTL_VERSION}/bin/linux/${KUBECTL_ARCH}/kubectl" -o /data/kubectl;
          curl -sL "https://dl.k8s.io/${KUBECTL_VERSION}/bin/linux/${KUBECTL_ARCH}/kubectl.sha256" -o /tmp/kubectl.sha256;
          echo "$(cat /tmp/kubectl.sha256) /data/kubectl" | sha256sum --check;
          rm /tmp/kubectl.sha256;
        fi;
        cp -v /data/kubectl /usr/local/bin/kubectl;
        chmod +x /usr/local/bin/kubectl;
        if [ ! -f /data/rakkess-amd64-linux ]; then
          curl -sL https://github.com/corneliusweig/rakkess/releases/download/v0.5.0/rakkess-amd64-linux.tar.gz -o /data/rakkess-amd64-linux.tar.gz;
          tar -C /data -xf  /data/rakkess-amd64-linux.tar.gz rakkess-amd64-linux;
        fi;
        chmod +x /data/rakkess-amd64-linux;
        cp -v /data/rakkess-amd64-linux /usr/local/bin/rakkess;
        echo 'if ! type _init_completion 2>/dev/null; then source /usr/share/bash-completion/bash_completion; fi;' >> ~/.bashrc;
        echo 'source <(kubectl completion bash | sed 's/--request-timeout=5s/--request-timeout=0/g')' >> ~/.bashrc;
        echo 'alias k=kubectl' >> ~/.bashrc;
        echo 'complete -o default -F __start_kubectl k' >> ~/.bashrc;
        trap exit INT TERM;
        while true; do sleep 5; done;
    workingDir: /data
    volumeMounts:
      - mountPath: /data
        name: data-volume
  restartPolicy: Never
  volumes:
    - name: data-volume
      emptyDir:
        sizeLimit: 500Mi