kin-config-ennvar-json.yaml

apiVersion: v1
kind: ConfigMap
metadata:
  name: config3
data:
  appconfig.json: |
    {
      "array": [
        1,
        2,
        3
      ],
      "boolean": true,
      "number": 123,
      "object": {
        "a": "b",
        "c": "d",
        "e": "f"
      },
      "string": "Hello World"
    }
---
apiVersion: v1
kind: Pod
metadata:
  name: pod4
spec:
  containers:
  - name: nginx
    image: nginx
    env:
      - name: APP_CONFIG_JSON
        valueFrom:
          configMapKeyRef:
            name: config3
            key: appconfig.json