نحوه تنظیم اولین خوشه Kubernetes و استقرار برنامه های کاربردی

$ brew install minikube

$ curl -LO https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64
$ sudo install minikube-linux-amd64 /usr/local/bin/minikube

$ curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
$ sudo install -o root -g root -m 0755 kubectl /usr/local/bin/kubectl

$ minikube version
$ kubectl version --client

$ minikube start --memory=4096 --cpus=2

$ kubectl cluster-info
$ kubectl get nodes

apiVersion: v1
kind: Namespace
metadata:
  name: todo-app

$ kubectl apply -f namespace.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-pvc
  namespace: todo-app
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: mysql
  namespace: todo-app
spec:
  selector:
    matchLabels:
      app: mysql
  template:
    metadata:
      labels:
        app: mysql
    spec:
      containers:
      - name: mysql
        image: mysql:8.0
        env:
        - name: MYSQL_ROOT_PASSWORD
          value: "password123"
        - name: MYSQL_DATABASE
          value: "todoapp"
        ports:
        - containerPort: 3306
        volumeMounts:
        - name: mysql-storage
          mountPath: /var/lib/mysql
      volumes:
      - name: mysql-storage
        persistentVolumeClaim:
          claimName: mysql-pvc
---
apiVersion: v1
kind: Service
metadata:
  name: mysql-service
  namespace: todo-app
spec:
  selector:
    app: mysql
  ports:
  - port: 3306
    targetPort: 3306

$ kubectl apply -f mysql.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: todo-web
  namespace: todo-app
spec:
  replicas: 3
  selector:
    matchLabels:
      app: todo-web
  template:
    metadata:
      labels:
        app: todo-web
    spec:
      containers:
      - name: todo-web
        image: node:16-alpine
        command: ["sh", "-c"]
        args:
        - |
          npm init -y
          npm install express mysql2
          cat > app.js << 'EOF'
          const express = require('express');
          const mysql = require('mysql2');
          const app = express();

          const db = mysql.createConnection({
            host: 'mysql-service',
            user: 'root',
            password: 'password123',
            database: 'todoapp'
          });

          app.get('/health', (req, res) => {
            res.json({ status: 'healthy', timestamp: new Date() });
          });

          app.get("https://dev.to/", (req, res) => {
            res.json({ 
              message: 'Todo App API',
              database: 'connected',
              replicas: process.env.HOSTNAME
            });
          });

          app.listen(3000, () => {
            console.log('Server running on port 3000');
          });
          EOF
          node app.js
        ports:
        - containerPort: 3000
        env:
        - name: NODE_ENV
          value: "production"
        livenessProbe:
          httpGet:
            path: /health
            port: 3000
          initialDelaySeconds: 30
          periodSeconds: 10
        readinessProbe:
          httpGet:
            path: /health
            port: 3000
          initialDelaySeconds: 5
          periodSeconds: 5
---
apiVersion: v1
kind: Service
metadata:
  name: todo-web-service
  namespace: todo-app
spec:
  selector:
    app: todo-web
  ports:
  - port: 80
    targetPort: 3000
  type: ClusterIP

$ kubectl apply -f web-app.yaml

$ minikube addons enable ingress

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: todo-ingress
  namespace: todo-app
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  rules:
  - host: todo.local
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: todo-web-service
            port:
              number: 80

$ kubectl apply -f ingress.yaml

$ echo "$(minikube ip) todo.local" | sudo tee -a /etc/hosts

$ kubectl get pods -n todo-app
$ kubectl describe pod  -n todo-app

$ kubectl logs -f deployment/todo-web -n todo-app
$ kubectl logs -f deployment/mysql -n todo-app

$ kubectl exec -it deployment/todo-web -n todo-app -- sh
$ kubectl exec -it deployment/mysql -n todo-app -- mysql -u root -p

$ kubectl scale deployment todo-web --replicas=5 -n todo-app
$ kubectl get pods -n todo-app -w