simple-stan.yml

---
apiVersion: v1
kind: ConfigMap
metadata:
  name: stan-config
data:
  stan.conf: |
    port: 4222
    http: 8222

    streaming {
     ns: "nats://nats:4222"

     id: stan
     store: file
     dir: /data/stan/store
     cluster {
       node_id: $POD_NAME
       log_path: /data/stan/log
       # Explicit names of resulting peers
       peers: ["stan-0", "stan-1", "stan-2"]
      }
    }
---
apiVersion: v1
kind: Service
metadata:
  name: stan
  labels:
    app: stan
spec:
  selector:
    app: stan
  clusterIP: None
  ports:
  - name: metrics
    port: 7777
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: stan
  labels:
    app: stan
spec:
  selector:
    matchLabels:
      app: stan
  serviceName: stan
  replicas: 3
  volumeClaimTemplates:
  - metadata:
      name: stan-sts-vol
    spec:
      accessModes:
      - ReadWriteOnce
      volumeMode: "Filesystem"
      resources:
        requests:
          storage: 1Gi
  template:
    metadata:
      labels:
        app: stan
    spec:
      # Prevent NATS Streaming pods running in same host.
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - topologyKey: "kubernetes.io/hostname"
            labelSelector:
              matchExpressions:
              - key: app
                operator: In
                values:
                - stan
      # STAN Server
      containers:
      - name: stan
        image: nats-streaming:0.16.2
        ports:
        - containerPort: 8222
          name: monitor
        - containerPort: 7777
          name: metrics
        args:
         - "-sc"
         - "/etc/stan-config/stan.conf"

        # Required to be able to define an environment variable
        # that refers to other environment variables.  This env var
        # is later used as part of the configuration file.
        env:
        - name: POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name
        - name: POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        volumeMounts:
          - name: config-volume
            mountPath: /etc/stan-config
          - name: stan-sts-vol
            mountPath: /data/stan

        # Disable CPU limits.
        resources:
          requests:
            cpu: 0

        livenessProbe:
          httpGet:
            path: /
            port: 8222
          initialDelaySeconds: 10
          timeoutSeconds: 5
      volumes:
      - name: config-volume
        configMap:
          name: stan-config