Extension to Fleet to add maintenance windows

cronjob.yaml

apiVersion: batch/v1
kind: CronJob
metadata:
  name: update-maint-window
  namespace: fleet-default
spec:
  schedule: "1,16,31,46 * * * *"
  jobTemplate:
    spec:
      template:
        spec:
          serviceAccountName: fleet-mw
          containers:
          - name: update-mw
            image: registry.opensuse.org/home/atgracey/utilities/containerfile/fmw:latest
            imagePullPolicy: Always
            
            command:
            - /bin/bash
            - -c
            - |
              DOTW=`date +"%a"` 
              DATE=`date +"%Y%m%d"` 
              CURRTIME=`date +"%s"` 
              WINDOWS=`kubectl get maintenancewindows.fleet.cattle.io -A -ojsonpath='{.items}'` 
              # maintenancewindows.fleet.cattle.io/name 
              CLUSTERS=`kubectl get clusters.fleet.cattle.io -A -ojsonpath='{range .items[?(@.metadata.labels.maintenancewindows\.fleet\.cattle\.io/name)]}{.metadata.name}{"\t"}{.metadata.namespace}{"\t"}{.metadata.labels.maintenancewindows\.fleet\.cattle\.io/name}{"\t"}{.spec.paused}{"\n"}'` 
              # TODO: need to handle empty schedule label 
              while read -r name namespace scheduleName paused 
              do 
                [[ -z "$name" ]] && continue
                printf '%s\n' "$name in $namespace is using schedule $scheduleName and paused is currently set to $paused" 
                declare shouldBePaused=false 
                # Get associated schedule and it's active windows 
                activeWindows=`echo $WINDOWS | jq -r ".[] | select(.metadata.name | test(\"test-window$\")) | [.spec.windows[] | select(.recurrance | test(\"^(daily|$DOTW|$DATE)\$\"))] | .[] | \"\(.startTime) \(.stopTime)\""` 
                
                while read -r start stop 
                do 
                  startTS="$(date -d $start +'%s')" 
                  stopTS="$(date -d $stop +'%s')" 
                  if [ "${CURRTIME}" -ge "${startTS}" -a "${CURRTIME}" -lt "${stopTS}" ] 
                  then 
                    shouldBePaused=true 
                  fi 
                done <<< "$activeWindows" 
                kubectl patch clusters.fleet.cattle.io -n $namespace $name --type='json' -p="[{\"op\":\"replace\",\"path\":\"/spec/paused\",\"value\":$shouldBePaused}]" 
              done <<< "$CLUSTERS"
          restartPolicy: OnFailure

mw-crd.yaml

apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
  # name must match the spec fields below, and be in the form: <plural>.<group>
  name: maintenancewindows.fleet.cattle.io
spec:
  # group name to use for REST API: /apis/<group>/<version>
  group: fleet.cattle.io
  # list of versions supported by this CustomResourceDefinition
  versions:
    - name: v1alpha1
      # Each version can be enabled/disabled by Served flag.
      served: true
      # One and only one version must be marked as the storage version.
      storage: true
      schema:
        openAPIV3Schema:
          type: object
          properties:
            spec:
              type: object
              properties:
                windows:
                  type: array
                  items:
                    type: object
                    properties:
                      recurrance:
                        # This would either be "daily", a 3 letter day of the week (Mon-Sun), or an ISO 8601 date (YYYYMMDD) for a single window
                        type: string
                        default: "daily"
                      startTime:
                        type: string
                      stopTime:
                        type: string
                      # timezone:
                        ### How to handle different timezones... Should calculate with the TZ of where the cluster is located
  scope: Namespaced
  names:
    plural: maintenancewindows
    singular: maintenancewindow
    kind: MaintenanceWindows
    shortNames:
    - mw

serviceaccount.yaml

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: fleet-mw
rules:
  - apiGroups:
      - fleet.cattle.io
    resources:
      - maintenancewindows
    verbs:
      - list
      - get
  - apiGroups:
      - fleet.cattle.io
    resources:
      - clusters
    verbs:
      - list
      - get
      - update
      - patch
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: fleet-mw
  namespace: fleet-default
automountServiceAccountToken: true
--- 
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: fleet-mw-sa
  namespace: fleet-default
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: fleet-mw
subjects:
  - kind: ServiceAccount
    name: fleet-mw
    namespace: fleet-default