learn/kubernetes/example/webapp.yaml

# deployement and service for mongodb
# https://kubernetes.io/docs/concepts/workloads/controllers/deployment/
apiVersion: apps/v1
kind: Deployment
metadata:
  name: webapp-deployment
  labels:
    app: webapp
spec: # deployement-specific
  replicas: 1
  selector:
    matchLabels:
      app: webapp
  template: # deployement for the pods
    metadata:
      labels:
        app: webapp
    spec:
      containers: # https://hub.docker.com/_/mongo
      - name: webapp
        image: nanajanashia/k8s-demo-app:v1.0  # demo web app
        ports:
        - containerPort: 3000
        env: #add demo information
        - name: USER_NAME
          valueFrom: 
            secretKeyRef:  # get from secrets
              name: mongo-secret
              key: mongo-user
        - name: USER_PWD
          valueFrom: 
            secretKeyRef:  # get from secrets
              name: mongo-secret
              key: mongo-password
        - name: DB_URL
          valueFrom: 
            configMapKeyRef:  # get from configMap
              name: mongo-config
              key: mongo-url
--- # "new file"
# https://kubernetes.io/docs/concepts/services-networking/service/
apiVersion: v1
kind: Service
metadata:
  name: webapp-service
spec:
  type: NodePort # external service port type
  selector:
    app: webapp
  ports:
    - protocol: TCP
      port: 3000
      targetPort: 3000
      nodePort: 30100 # see https://kubernetes.io/docs/concepts/services-networking/service/#type-nodeport for ranges