---
apiVersion: "apps/v1beta1"
kind: StatefulSet
metadata:
  name: elassandra
spec:
  serviceName: elassandra
  replicas: 3
  updateStrategy:  
    type: RollingUpdate
  template:
    metadata:
      labels:
        app: elassandra
    spec:
      # See https://pracucci.com/graceful-shutdown-of-kubernetes-pods.html
      terminationGracePeriodSeconds: 300
      securityContext:
        # allows read/write access for mounted volumes  
        # by users that belong to a group with gid: 999
        fsGroup: 999
      initContainers:
      - name: increase-vm-max-map-count
        image: busybox
        imagePullPolicy: IfNotPresent
        command: ["sysctl", "-w", "vm.max_map_count=1048575"]
        securityContext:
          privileged: true
      - name: increase-ulimit
        image: busybox
        command: [ "sh","-c","ulimit -l unlimited" ]
        securityContext:
          privileged: true
      containers:
        - name: elassandra
          image: strapdata/elassandra:5.5.0.22-rc1
          imagePullPolicy: Always
          securityContext:
            privileged: false
            # applying fix in: https://github.com/kubernetes/kubernetes/issues/3595#issuecomment-287692878 
            # https://docs.docker.com/engine/reference/run/#operator-exclusive-options
            capabilities:
              add: ["IPC_LOCK", "SYS_RESOURCE"]
          livenessProbe:
            tcpSocket:
              port: 7000
            initialDelaySeconds: 15
            periodSeconds: 5
          readinessProbe:
            exec:
              command: [ "/bin/bash", "-c", "/ready-probe.sh" ]
            initialDelaySeconds: 15
            timeoutSeconds: 5
          lifecycle:
            preStop:
              exec:
                command: ["/bin/sh", "-c", "exec nodetool drain"]
          ports:
            - containerPort: 7000
              name: intra-node
            - containerPort: 7001
              name: tls-intra-node
            - containerPort: 7199
              name: jmx
            - containerPort: 9042
              name: cql
            - containerPort: 9200
              name: http
              protocol: TCP
            - containerPort: 9300
              name: transport
              protocol: TCP
          env:
            # environment variables to be directly refrenced from the configuration
            - name: NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
            - name: POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
            - name: POD_IP
              valueFrom:
                fieldRef:
                  fieldPath: status.podIP

            - name: CASSANDRA_SEEDS
              value: elassandra-0.elassandra.default.svc.cluster.local
            - name: MAX_HEAP_SIZE
              value: 2048M
            - name: HEAP_NEWSIZE
              value: 512M
            - name: CASSANDRA_CLUSTER_NAME
              value: "Cassandra"
            - name: CASSANDRA_DC
              value: "DC1"
            - name: CASSANDRA_RACK
              value: "r1"
            - name: CASSANDRA_ENDPOINT_SNITCH
              value: GossipingPropertyFileSnitch
#            - name: CASSANDRA_DAEMON
#              value: "org.apache.cassandra.service.CassandraDaemon"

            # logging variables
            - name: LOGBACK_org_elassandra_discovery
              value: DEBUG

          volumeMounts:
            - name: elassandra-data
              mountPath: /var/lib/cassandra
  volumeClaimTemplates:
    - metadata:
        name: elassandra-data
      spec:
        accessModes: ["ReadWriteOnce"]
        # Define your own storageClassName if needed.
        storageClassName: managed-premium
        resources:
          requests:
            storage: 16Gi