Kubernetes Deployment

Run MAPS Messaging on Kubernetes with a pinned image tag and production‑grade settings.

Use a specific version tag (e.g., 4.0.1) or parameterize via Helm/Kustomize. Avoid :latest in production.

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Prerequisites

• Kubernetes 1.23+ and kubectl configured
• StorageClass available for PersistentVolumeClaims
• Optional: Prometheus stack (Operator or scraper), Ingress controller

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Quick Start (Deployment + Service + PVC)

Minimal example that exposes MQTT (1883), AMQP (5672) and REST API (8080). Add/remove ports as needed.> Replace {MAPS_VERSION} with your release (e.g., 4.0.1).

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: maps-data
spec:
  accessModes: ["ReadWriteOnce"]
  resources:
    requests:
      storage: 10Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: maps-messaging
spec:
  replicas: 3
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 1
  selector:
    matchLabels:
      app: maps-messaging
  template:
    metadata:
      labels:
        app: maps-messaging
    spec:
      securityContext:
        runAsUser: 10001
        runAsGroup: 10001
        runAsNonRoot: true
        fsGroup: 10001
      containers:
        - name: maps-messaging
          image: mapsmessaging/maps-messaging:{MAPS_VERSION}
          imagePullPolicy: IfNotPresent
          ports:
            - name: mqtt
              containerPort: 1883
            - name: amqp
              containerPort: 5672
            - name: http
              containerPort: 8080
            # Optional: Prometheus JMX exporter (if enabled as -javaagent)
            # - name: metrics
            #   containerPort: 9404
          env:
            # Example envs; keep minimal, add only what's used in your setup
            - name: SCHEMA_VALIDATION
              value: "true"
          volumeMounts:
            - name: maps-config
              mountPath: /opt/maps/config
              readOnly: true
            - name: maps-schemas
              mountPath: /opt/maps/schemas
              readOnly: true
            - name: maps-data
              mountPath: /data
          readinessProbe:
            httpGet:
              path: /health
              port: http
            initialDelaySeconds: 10
            periodSeconds: 10
            timeoutSeconds: 3
            failureThreshold: 3
          livenessProbe:
            httpGet:
              path: /api/v1/ping
              port: http
            initialDelaySeconds: 30
            periodSeconds: 20
            timeoutSeconds: 3
            failureThreshold: 3
          resources:
            requests:
              cpu: "500m"
              memory: "1Gi"
            limits:
              cpu: "1000m"
              memory: "2Gi"
      volumes:
        - name: maps-config
          configMap:
            name: maps-config
            optional: true
        - name: maps-schemas
          configMap:
            name: maps-schemas
            optional: true
        - name: maps-data
          persistentVolumeClaim:
            claimName: maps-data
---
apiVersion: v1
kind: Service
metadata:
  name: maps-messaging
  labels:
    app: maps-messaging
  # If using Prometheus without the Operator, you can annotate for scraping:
  # annotations:
  #   prometheus.io/scrape: "true"
  #   prometheus.io/port: "9404"
spec:
  type: ClusterIP
  selector:
    app: maps-messaging
  ports:
    - name: mqtt
      port: 1883
      targetPort: mqtt
    - name: amqp
      port: 5672
      targetPort: amqp
    - name: http
      port: 8080
      targetPort: http
    # - name: metrics
    #   port: 9404
    #   targetPort: metrics

Expose externally with Service.type: LoadBalancer or via an Ingress for the REST API (8080). Expose only the ports you actually need.

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Configuration & Data

• Config: mount configuration into /opt/maps/config and schemas into /opt/maps/schemas using ConfigMaps (as shown). To populate, create maps-config and maps-schemas ConfigMaps from your files:

  kubectl create configmap maps-config --from-file=./conf/
  kubectl create configmap maps-schemas --from-file=./schemas/

• Data: persistent runtime data is stored at /data. Size your PVC accordingly.

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Health Probes

• Readiness: GET /health (200 indicates ready). The body returns OK | Warning | Error. Kubernetes HTTP probes do not inspect the body; if you require body-based logic, use a sidecar or an exec probe.
• Liveness: GET /api/v1/ping should return {"status":"Success"} with 200.

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Scaling & Availability

• Replicas: start with 3 for HA. Adjust based on throughput and persistence mode.
• Disruption control: add a PodDisruptionBudget to avoid dropping below 1 pod during maintenance:

  apiVersion: policy/v1
  kind: PodDisruptionBudget
  metadata:
    name: maps-pdb
  spec:
    minAvailable: 2
    selector:
      matchLabels:
        app: maps-messaging

• Spread: use pod anti‑affinity or topology spread constraints to avoid co‑locating all replicas on the same node/zone.

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Observability (Prometheus & Jolokia)

• Prometheus: if you’ve enabled the JMX Exporter (-javaagent), expose 9404 and either:
  • add prometheus.io/* annotations to the Service, or
  • create a ServiceMonitor (Prometheus Operator).
• Jolokia: optional port 8778 if you use JMX over HTTP.

See the dedicated guide: Prometheus (JMX Exporter)

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Security

• Run as non‑root (UID/GID set above).
• Read‑only root filesystem where possible; ensure /data is writable.
• NetworkPolicies (optional) to restrict inbound/outbound traffic.

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