kube/shared/mongoexpress.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: mongoexpress
spec:
  revisionHistoryLimit: 0
  replicas: 1
  selector:
    matchLabels:
      app: mongoexpress
  template:
    metadata:
      labels:
        app: mongoexpress
    spec:
      containers:
        - name: mongoexpress
          image: mongo-express
          ports:
           - name: mongoexpress
             containerPort: 8081
          env:
            - name: ME_CONFIG_MONGODB_URL
              valueFrom:
                secretKeyRef:
                  name: mongodb-application-readwrite
                  key: connectionString.standard
            - name: ME_CONFIG_MONGODB_ENABLE_ADMIN
              value: 'false'
---
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: mongoexpress
spec:
  podSelector:
    matchLabels:
      app: mongoexpress
  policyTypes:
  - Egress
  egress:
    - to:
      - podSelector:
          matchLabels:
            app: mongodb-svc
      ports:
      - port: 27017