apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
   name: configmap-updater
   namespace: default
spec:
  template:
    metadata:
      labels:
        component: configmap-monitor 
        system: kube 
      annotations:
        pod.alpha.kubernetes.io/initialized: "true"
        pod.alpha.kubernetes.io/init-containers: '[
          {
              "name": "copy-config",
              "image": "docker.io/port/centos-binary-kolla-kube-toolbox:3.0.1",
              "command": [
                  "/bin/sh",
                  "-c",
                  "cp -a /tmp/main-process-configmap/..data/* /tmp/pod-main-config/;
                   kubectl get configmap main-process-configmap -o json | jq -r ''.metadata.resourceVersion '' > /tmp/configmap-monitor/configmap-version.txt; "
              ],
              "volumeMounts": [
                  {
                      "name": "pod-main-config",
                      "mountPath": "/tmp/pod-main-config"
                  },
                  {
                      "name": "configmap-monitor",
                      "mountPath": "/tmp/configmap-monitor"
                  },
                  {
                      "name": "main-process-configmap",
                      "mountPath": "/tmp/main-process-configmap"
                  }
              ]
          }
        ]'
    spec:
      containers:
        - image: docker.io/port/centos-binary-kolla-kube-toolbox:3.0.1
          name: main
          livenessProbe:
            exec:
              command:
              - /bin/bash
              - -c
              - |
                 original_version=$(</tmp/configmap-monitor/configmap-version.txt);
                 current_version=$(kubectl get configmap main-process-configmap -o json | jq -r '.metadata.resourceVersion ')
                 echo "Original version - $original_version, Current version - $current_version";
                 if [ $original_version != $current_version ]; then
                    echo 'Configmap got changed need to restart POD';
                    kubectl delete pod $HOSTNAME;
                 fi;
                 exit 0;
            initialDelaySeconds: 15
            timeoutSeconds: 1
          command:
            - /bin/bash
            - -c
            - |
               config_value=$(cat /tmp/main-process-config/config.json | jq -r '.variable ');
               while true; 
                 do 
                    echo $config_value; 
                    sleep 10; 
               done;
          volumeMounts:
            - mountPath: /tmp/main-process-config 
              name: pod-main-config
            - mountPath: /tmp/configmap-monitor
              name: configmap-monitor
      volumes:
        - name: pod-main-config
          emptyDir: {}
        - name: configmap-monitor
          emptyDir: {}
        - name: main-process-configmap
          configMap:
            name: main-process-configmap