Target

Continuing from the previous article on NFS file systems, the current requirement is to be able to control the applications running in the cluster. For example, if we need to run parallel cross-node program A, we need to schedule and stop the running program B. This requires building a messaging system that can perform operational tasks based on message drivers.

This requires building a messaging system that can perform message-driven operational tasks. ## Vision and Basic Architecture Design ##

Swift is set to be the next generation machine learning language for Tensorflow, see Swift for Tensorflow for current attempts to write applications in Swift. 2.

2. use the MQTT protocol to send and receive data that needs to be processed. 3. use TinyML technology to collect data.

3. using TinyML technology to collect data generated by sensors on home appliances to make the appliances smarter.

The current idea is to use RabbitMQ as the message middleware, Swift to write server-side applications to push messages, and the client needs a UI application to accept and process the corresponding message events.

Discover Node-Red

Node-Red is a process-based visual programming tool developed by IBM.

I personally find its advantages to be the speed of developing prototype IoT applications, support for Arduino, Raspberry Pi and other devices, easy to use, event-driven, native nodejs development language, and support for extensible plug-ins.

Runs on K3s

node-red.yaml

---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: node-red
  namespace: science
  labels:
    app: node-red
spec:
  replicas: 1
  selector:
    matchLabels:
      app: node-red
  template:
    metadata:
      labels:
        app: node-red
    spec:
      containers:
      - name: node-red
        image: $image
        imagePullPolicy: Always
        ports:
        - containerPort: 1880
        volumeMounts:
        - mountPath: /data
          name: data-volume
      volumes:
      - name: data-volume
        persistentVolumeClaim:
          claimName: node-red-pvc

---
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: node-red-pvc
  namespace: science
  annotations:
    volume.beta.kubernetes.io/storage-class: "managed-nfs-storage"
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 6Gi

---
apiVersion: v1
kind: Service
metadata:
  name: node-red
  namespace: science
spec:
  selector:
    app: node-red
  ports:
    - protocol: TCP
      port: 1880
      targetPort: 1880

---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: node-red-ingress
  namespace: science
spec:
  rules:
  - host: foo.bar.host
    http:
      paths:
      - backend:
          serviceName: node-red
          servicePort: 1880	  

Run RabbitMQ On K3s

rabbitmq-conf-rabbitmq-env-configmap.yaml

apiVersion: v1
data:
  RABBITMQ_DEFAULT_PASS: xxxxx
  RABBITMQ_DEFAULT_USER: admin
  RABBITMQ_HOST: rabbitmq
  RABBITMQ_PORT: "5672"
kind: ConfigMap
metadata:
  name: rabbitmq-conf-rabbitmq-env
  namespace: science

rabbitmq-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: rabbitmq
  name: rabbitmq
  namespace: science
spec:
  replicas: 1
  selector:
    matchLabels:
      app: rabbitmq
  template:
    metadata:
      labels:
        app: rabbitmq
    spec:
      hostname: rabbitmq
      containers:
      - env:
        - name: RABBITMQ_DEFAULT_PASS
          valueFrom:
            configMapKeyRef:
              key: RABBITMQ_DEFAULT_PASS
              name: rabbitmq-conf-rabbitmq-env
        - name: RABBITMQ_DEFAULT_USER
          valueFrom:
            configMapKeyRef:
              key: RABBITMQ_DEFAULT_USER
              name: rabbitmq-conf-rabbitmq-env
        - name: RABBITMQ_HOST
          valueFrom:
            configMapKeyRef:
              key: RABBITMQ_HOST
              name: rabbitmq-conf-rabbitmq-env
        - name: RABBITMQ_PORT
          valueFrom:
            configMapKeyRef:
              key: RABBITMQ_PORT
              name: rabbitmq-conf-rabbitmq-env
        image: 192.168.1.114:5000/rabbitmq:3.8.5-management-alpine
        ports:
          - containerPort: 5672
            name: port
            protocol: TCP
          - containerPort: 15672
            name: web-port
            protocol: TCP
        name: rabbitmq
        volumeMounts:
        - mountPath: /var/lib/rabbitmq
          name: rabbitmq-volume
      restartPolicy: Always
      volumes:
      - name: rabbitmq-volume
        persistentVolumeClaim:
          claimName: rabbitmq-volume

rabbitmq-service.yaml

apiVersion: v1
kind: Service
metadata:
  name: rabbitmq
  namespace: science
  labels:
    app: rabbitmq
spec:
  ports:
    - protocol: TCP
      port: 5672
      targetPort: 5672
      name: port
    - protocol: TCP
      port: 15672
      targetPort: 15672
      name: web-port
  selector:
    app: rabbitmq

rabbitmq-volume-persistentvolumeclaim.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: rabbitmq-volume
  namespace: science
spec:
  accessModes:
    - ReadWriteOnce
  storageClassName: managed-nfs-storage
  resources:
    requests:
      storage: 10Gi