apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: my-network-policy
spec:
  podSelector:
    matchLabels:
      role: db
  ingress:
    - from:
      - podSelector:
        matchLabels:
          app: db
  egress:
    - to:
      - namespaceSelector:
        matchLabels:
          app: web
      ports:
        - protocol: TCP
          port: 80