pod-configmap.yaml

# Create Namespace
apiVersion: v1
kind: Namespace
metadata:
  name: pod-configmap-namespace
---
# Create Game Object ConfigMap
apiVersion: v1
kind: ConfigMap
metadata:
  name: game-objects-configmap
  namespace: pod-configmap-namespace
data:
  # property-like keys; each key map to a single value
  player_initial_lives: "7"
  # file-like keys
  game.properties: |
    enemy.types=aliens,monsters
    player.maximum-lives=5
immutable: true
---
# Create Game UI ConfigMap
apiVersion: v1
kind: ConfigMap
metadata:
  name: game-ui-configmap
  namespace: pod-configmap-namespace
data:
  # property-like keys; each key map to a single value
  ui_properties_file_name: "user-interface.properties"
  # file-like keys
  user-interface.properties: |
    color.good=purple
    color.bad=yellow
    allow.textmode=true
immutable: false
---
# Create Game App Pod
apiVersion: v1
kind: Pod
metadata:
  name: game-app-pod
  namespace: pod-configmap-namespace
  labels:
    name: my-game-app
spec:
  containers:
    - name: app
      image: alpine
      command: ["sleep", "3600"]
      # Mount game ui configmap as env or envFrom
      # Use "env" when you want to mount few keys only as env from configmap
      env:
        - name: UI_PROPERTIES_FILE_NAME
          valueFrom:
            configMapKeyRef:
              name: game-ui-configmap          # ConfigMap name
              key: ui_properties_file_name     # key name from configmap to fetch value from
      # Use "envFrom" when you want to mount whole configmap as Env
      envFrom:
        - configMapRef:
            name: game-ui-configmap
      # Mount game objects configmap as volume
      volumeMounts:
        - name: game-app-volume
          mountPath: "/config"
          readOnly: true
  volumes:
    # You create volumes at the Pod level then mount them into containers inside that Pod
    - name: game-app-volume
      configMap:
        # Provide the name of the ConfigMap you want to mount
        name: game-objects-configmap
        # An array of keys from the ConfigMap to create as files
        items:
          - key: "player_initial_lives"
            path: "player_initial_lives_data" # file will be created in /config folder having only player_initial_lives data in it
          - key: "game.properties"
            path: "game_properties_data"      # file will be created in /config folder having only game.properties data in it